Note: Descriptions are shown in the official language in which they were submitted.
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HEAT EXCHANGER
FIELD OF THE INVENTION
The present invention concerns heat exchangers, and more particularly to blade-
type
heat exchangers for recovering heat from fluids.
BACKGROUND OF THE INVENTION
Heat exchangers are well-known and widely used in a number of environments to
recover thermal energy from fluids. The thermal energy, if not recovered,
would be lost
to the environment. Generally speaking, heat exchangers work by transferring
heat
from one fluid to another via a solid wall, which separates the two fluids.
This
straightforward principle has been used to recover heat from waste water (so
called
"grey water") in, for example, household shower and bath systems. A number of
designs of heat exchangers that have been used with household shower/bath
systems
are described as follows.
US Patent No. 5,143,149 issued to Kronberg on Sept. 1, 1992 concerns a heat
recovery system that includes a heat exchanger and a mixing valve. The heat
exchanger appears to include a drain trap with an inner coiled tube, a baffle
plate and a
waste water outlet. The inner coiled tube includes a cold water inlet and a
pre-heated
water outlet in fluid communication with each other and is coiled around the
inside wall
of a cylindrical member. A waste water inlet is located in the drain trap such
that waste
water enters the cylinder through the inlet, contacts the baffle plate and is
deflected
away from a solid central portion towards a perforated outer region such that
the waste
water gradually moves downwardly through the cylinder until it reaches the
bottom.
Cold water located in the coiled tube moves in a generally upward direction
opposite to
the waste water as it flows downwardly over the coiled tube to heat the cold
water.
Heat exchange appears to take place through the walls of the coiled tube. The
heated
water then exits the heat exchanger via the outlet. Ths design is simple and
relies on
the counter-flow principal of heat exchange across a thermally conductive wall
of the
coiled pipe. While this apparatus uses the heat from waste drain water to heat
cold
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water via a heat exchanger, it does so by direct contact of the waste water
with the
coiled cold water tube.
US Patent No. 4,821,793 issued to Sheffield on Apr. 18, 1989 discloses a tub
and
shower floor heat exchanger in which a heat exchanger cover is supported on
the tub
floor by a number of supports, each having an opening therein. The heat
exchanger
cover is disposed away from the tub floor and includes a gap between the cover
and
the tub floor. A heat exchange tube is connected to a cold water supply line,
the heat
exchange tube being arranged directly beneath the heat exchanger cover. Water
flowing from a shower head strikes the tub bottom and, as waste water flows
towards a
drain hole, it is forced back and forth over an extended path by means of the
supports
which serve as a baffle system. As the waste water moves through the baffle
system it
moves through the openings and is maintained in a heat exchange relationship
with the
heat exchange tube over an extended period of time, thereby heating the cold
water in
the heat exchange tube, which is then fed back to a water line.
Disadvantageously, a
user of the tub may trip over the raised heat exchanger cover. The tub may
also be
difficult to clean and maintain.
US Patent No. 4,619,311 issued to Vasile et al. on Oct. 28, 1986 discloses a
counter-
flow heat exchanger system in which waste water exits a shower tub via an
essentially
vertical waste pipe. A lower portion of the waste pipe is surrounded by a
jacket into
which is fed cold water in a coaxial counter-flow orientation such that waste
water
travelling down the waste water pipe exchanges its heat with the cold water
travelling
up the jacket thereby heating the cold water by heat transfer across the waste
water
pipe wall. The heated water exits directly to the shower system or moves to a
hot water
heater tank.
US Patent 4,472,372 issued to Hunter on Feb. 8, 1983 discloses a heat
exchanger that
is located in a drain pipe of a shower bath. A cylindrical member is in
communication
with the drain hole and includes, on the interior, a coiled heat conducting
conduit. The
coiled conduit includes a coiled copper tube which extends the full length of
the
cylindrical housing and a second heat conducting coil that is disposed within
the
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annulus of the first heat conducting coil. The coils are each fed by a common
inlet
conduit which feeds cold water through the coiled conduits such that waste
water
flowing into the cylindrical member heats the cold water flowing through the
coils which
then exits via a common outlet towards the mixing valve of the shower unit. A
baffle in
the form of a central core member is disposed within the annulus of the
central coil and
appears to cause the water flowing from the drain pipe to be maintained in
contact with
both coils so as to maximize heat transfer. The heat exchange in this design
takes
place by direct contact of the waste water with the cold water conduit.
US Patent No. 4,304,292 issued to Cardone et al. on December 8, 1981 discloses
a
shower unit in which a U-shaped conduit as part of a heat exchange apparatus.
A heat
exchange conduit is coiled around the exterior of the U-shaped conduit. Cold
water
flows through the coiled conduit and is heated by the waste water flowing
through the
U-shaped conduit, although there is no indication as to the nature of the
contact
between the coils and the U-shaped conduit. It is possible that the heat
exchange is
occuring across the walls of the two conduits. The coiled cold water conduit
may also
be located internally of the U-shaped conduit. Heat exchange appears to take
place by
direct contact of the waste water with the coiled cold water conduit.
US Patent No. 4,300,247 issued to Berg on November 17, 1981 discloses a heat
exchanger integral with the base of a shower unit in which a drain hole is in
communication with the heat exchanger. The heat exchanger has a pair of so-
called
drain water flow through compartments, which are separated by a heat
conducting
material from a pair of cold water flow through compartments. Cold water is
fed into the
compartments and, after absorbing heat from the drain water, exits via an
output. The
heat exchange appears to occur by direct contact of water with the surface of
a supply
of cold water; in this case, however, instead of being a conduit, the cold
water is located
in compartments. Waste water fills one side of a number of serpentine
compartments
up to a line and exchanges heat across the folded layers of heat conductive
material
into complementary cold water containing compartments. Presumably, this folded
arrangement of the heat conductive material allows for a great surface area
over which
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the heat echange can take place. The heat exchnage takes place by direct
contact of
waste water on the container of cold water.
US Patent No. 6,722,421 issued to MacKelvie on April 20, 2004 discloses a
rather
complex arrangement of either vertical or horizontal heat exchangers which
have built-
in heat storage for continuous heat recovery from waste drain water. A
vertical heat
exchanger includes a drain conduit connected to a drain water source, a water
reservoir
surrounding the drain conduit and a cold water conduit coiled around the water
reservoir. A number of nested convection chambers are located on the external
wall of
the drain conduit and hold a volume of water adjacent to the wall of the drain
conduit.
In operation, drain water in the drain conduit heats the volume of water in
the
chambers, which through convention flows into the reservoir thereby heating
same and
the cold water flowing through the coiled conduit. The horizontal version of
the heat
exchanger has a convention chambers that appears to "cup" the central drain
conduit
and operate on the same convection principle as described for the vertical
design.
Interestingly, simultaneous flow of cold water in the coiled conduit and waste
water in
the drain conduit is not necessary. There is no contact between the drain
conduit and
the cold water conduit.
US Patent No. 5,791,401 issued to Nobile on August 11, 1998 discloses a
portion of a
waste water conduit which is U-shaped. The drain coduit includes a number of
axially
disposed consecutive solid wall ridges and depressions, which are located
around the
entire inner surface of the drain conduit. A cold water conduit is coiled
around the
waste water conduit and includes a smooth, arcuate thermal transfer surface
complementary to the curvature of the cold water conduit sidewall. This design
appears to operate when the void in the U-shaped portion of the waste water
drain
conduit is entirely filled with waste water.
US Patent No. 5,740,857 issued to Thompson et al., April 21, 1998 discloses a
heat
recovery and storage device useful to recover heat from warm waste water in
which a
generally horizontal waste water conduit is surrounded by a cold water
reservoir. The
waste water conduit includes a number of projections made of a high thermally
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conductive material located on a lower external surface of the conduit and
which project
into the cold water reservoir so as to transfer heat to same. The upper
portion of the
conduit is made of a material which limits heat re-conduction. The cold water
is in direct
contact with the outer wall of the drain water conduit.
US Patent No. 4,256,170 issued to Crump on March 17, 1981 discloses a liquid-
to-
liquid heat exchanger which includes a number of fins located at a lower
portion of the
waste water conduit. The fins are arranged to define a generally serpentine
fluid
pathway within a jacket of cold water, which surrounds the waste water
conduit. The
fins are also used to transfer heat to the cold water and induce turbulence in
the cold
water flow.
Thus, there is a need for an improved heat exchange apparatus, in which the
fluids do
not contact each other and which provides efficient thermal energy transfer
across the
heat exchanger walls over a short pathway, and in which debris and maintenance
tooling can pass through the heat exchange apparatus.
SUMMARY OF THE INVENTION
We have designed a novel, blade-type, passive fluid-to-fluid heat exchange
apparatus,
which uses turbulators to induce and maintain turbulent flow to provide
unexpectedly
high efficiency heat recapture from waste water (also known as "grey water")
commonly
found in household shower and bath systems. Moreover, the blade members are
self-
supporting and do not require additional frames for support as is typically
required in
existing heat exchange designs.
Accordingly, in one aspect there is provided a heat exchange apparatus, the
apparatus
comprising: a hollow blade member having a first fluid inlet and a first fluid
outlet and a
first fluid passageway for a first fluid extending therebetween, the blade
member being
sized and shaped for location in a second fluid passageway for a second fluid,
the
blade member being configured to enhance thermal energy transfer between the
fluids
as they flow along their respective passageways.
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Accordingly in another aspect, there is provided a blade heat exchange
apparatus, the
apparatus comprising: at least one blade member having a first fluid inlet and
a first
fluid outlet, and a first fluid passageway for a first fluid extending
therebetween, the
blade member having a longitudinal blade axis; a second fluid passageway for a
second fluid, the second fluid passageway being sized and shaped to receive
therein
the blade member; the blade member has two blade walls, each blade wall having
an
inner and outer thermal transfer surface, the thermal transfer surfaces each
having a
plurality of spaced apart ridges and recesses, the ridges and recesses being
substantially parallel to each other, the ridges and recesses of the first
blade wall being
angled in a first direction relative to the longitudinal axis, the ridges and
recesses of the
second blade wall being angled in a second direction relative to the
longitudinal axis,
the second direction being different from the first direction so as to induce
cross flow in
the first and second fluids as they travel along their respective passageways.
Accordingly in another aspect, there is provided a heat exchange apparatus,
comprising: a central conduit having a conduit wall; an outer jacket
substantially
encasing the central conduit, the jacket being spaced apart from the conduit
wall to
define an enclosure and having a fluid inlet and a fluid outlet; a turbulator
located in the
enclosure, the turbulator having a first helical wire disposed in a clockwise
orientation
and a second helical wire disposed counterclockwise to the first helical wire
so as to
induce shear turbulent flow in a fluid as it flows through the enclosure and
contacts the
turbulator.
Accordingly in another aspect, there is provided a heat exchange apparatus,
the
apparatus comprising: a central conduit having a conduit wall; an outer jacket
substantially encasing the central conduit, the jacket being spaced apart from
the
conduit wall to define an enclosure and having a fluid inlet and a fluid
outlet; a mesh
turbulator located in the enclosure, the mesh turbulator being configured to
induce
shear and turbulent flow in a fluid as it flows through the enclosure and
contacts the
turbulator.
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Accordingly in one embodiment of the present invention there is provided a
heat
exchange apparatus, the apparatus comprising:
a) at least one hollow fin member having first and second thermal transfer
surfaces, the first thermal transfer surface defining a first fluid passageway
for a
first fluid, which first fluid being flowable along the first passageway in
contact
with the first thermal transfer surface; and
b) a second fluid passageway for a second fluid, the second fluid passageway
being located in intimate contact with the second thermal transfer surface,
such
that the first fluid when flowing along the first fluid passageway exchanges
thermal energy with the second fluid flowing along the second fluid
passageway.
Accordingly in another embodiment of the present invention there is provided a
heat
exchange apparatus, the apparatus comprising:
a) a channel member having first and second end portions, the channel member
having a plurality of hollow fin members extending between the first and
second end
portions, the fin members having first and second thermal transfer surfaces,
the first
thermal transfer surface defining a first fluid passageway, the first end
portion being
connectable to a source of a first fluid, the first fluid entering the first
end portion at a
first temperature and flowable along the first thermal transfer surface, the
first fluid
exiting the second end portion at a second temperature; and
b) a second fluid passageway having an inlet and an outlet, the second fluid
passageway being located in intimate contact with the second thermal transfer
surface,
the inlet being connectable to a source of a second fluid, the second fluid
entering the
inlet at a third temperature and flowable along the second fluid passageway,
such that
the first fluid when flowing along the first fluid passageway exchanges
thermal energy
with the second fluid flowing along the second fluid passageway, the second
fluid
exiting the outlet at a fourth temperature.
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Accordingly in one embodiment of the present invention there is provided a
heat
exchange apparatus, the apparatus comprising:
a) a channel member having first and second thermal transfer surfaces, at
least
one thermal transfer surface being uneven and defining a first fluid
passageway for a
first fluid; and
b) a second fluid passageway for a second fluid, the second fluid passageway
being located in intimate contact with the second thermal transfer surface,
the flow of at
least one of the fluids being disrupted such that the first fluid when flowing
along the
first fluid passageway exchanges thermal energy with the second fluid flowing
along the
second fluid passageway.
Accordingly in another embodiment of the present invention, there is provided
a heat
exchange apparatus, the apparatus comprising:
a) a fluid passageway having a fluid passageway sidewall of a membraneous
material, the material having at least one heat conductive surface locatable
in intimate
contact with a portion of a conduit sidewall, the conduit having an inlet and
an outlet, a
first fluid entering the inlet at a first temperature and exiting the outlet
at a second
temperature, the fluid passageway sidewall being spreadable over an area of
the
conduit sidewall, the fluid passageway having a fluid passageway inlet and a
fluid
passageway outlet, a second fluid entering the fluid passageway inlet at a
third
temperature and exiting the fluid passageway outlet at a fourth temperature.
Accordingly, in another embodiment, there is provided a heat exchange
apparatus, the
apparatus comprising:
a) a conduit having an arcuate conduit member having first and second ends,
and an arcuate heat exchanger having first and second connecting portions
sealingly
connectable to the respective first and second ends, the heat exchanger having
first
and second thermal transfer surfaces, an amount of a first fluid entering the
conduit at a
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first temperature and being in contact with the first thermal transfer surface
and exiting'
the conduit at a second temperature; and
b) a fluid passageway having a fluid passageway sidewall of a membraneous
material, the material having at least one heat conductive surface locatable
in intimate
contact with the second thermal transfer surface, the fluid passageway
sidewall being
spreadable over an area of the second thermal transfer surface, the fluid
passageway
having a fluid passageway inlet and a fluid passageway outlet, a second fluid
entering
the fluid passageway inlet at a third temperature and exiting the fluid
passageway outlet
at a fourth temperature.
Accordingly in another embodiment of the present invention, there is provided
a heat
exchange apparatus for use with a P-Trap having an inlet and an outlet, the P-
Trap
having a first drain portion disposed orthogonal to the ground and connectable
to a
drain, a second drain portion being disposed away from the ground in a
downward
gradient, and a U-shaped drain portion interconnecting the first and second
drain
portions, the apparatus comprising:
a) a fluid passageway having a fluid passageway sidewall of a membraneous
material, the material having at least one heat conductive surface locatable
in intimate
contact with a sidewall of first drain portion, the second drain portion and
the U-shaped
portion, a first fluid entering the inlet at a first temperature and exiting
the outlet at a
second temperature, the fluid passageway sidewall being spreadable over an
area of
the first drain portion, the second drain portion and the U-shaped portion
sidewall, the
fluid passageway having a fluid passageway inlet and a fluid passageway
outlet, a
second fluid entering the fluid passageway inlet at a third temperature and
exiting the
fluid passageway outlet at a fourth temperature.
Accordingly in another embodiment of the present invention, there is provided
a
drainage apparatus for use with a drain trap, the apparatus comprising:
a) a P-Trap having an inlet and an outlet, the P-Trap having a first drain
portion
being disposed orthogonal to the ground and connectable to the drain trap, a
second
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drain portion being disposed away from the ground in a downward gradient and a
U-
shaped drain portion interconnecting the first and second drain portions;
b) the second drain portion comprising:
i) an arcuate conduit member having first and second ends, and an
arcuate heat exchanger having first and second connecting portions sealingly
connectable to the respective first and second ends, the heat exchanger having
first and second thermal transfer surfaces, an amount of a first fluid
entering the
second drain portion at a first temperature and being in contact with the
first
thermal transfer surface and exiting the second drain portion at a second
temperature; and
ii) a fluid passageway having a fluid passageway sidewall of a
membraneous material, the material having at least one heat conductive surface
locatable in intimate contact with the second thermal transfer surface, the
fluid
passageway sidewall being spreadable over an area of the second thermal
transfer surface, the fluid passageway having a fluid passageway inlet and a
fluid passageway outlet, a second fluid entering the fluid passageway inlet at
a
third temperature and exiting the fluid passageway outlet at a fourth
temperature.
Accordingly in another embodiment of the present invention, there is provided
a
drainage apparatus for use with a drain trap, the apparatus comprising:
a) a P-Trap having a drain portion disposed orthogonal to the ground and
connectable to the drain trap and a U-shaped drain portion;
b) a heat exchanger in fluid communication with the U-shaped portion, the heat
exchanger having a channel member having first and second end portions, the
channel
member having a plurality of hollow fin members extending between the first
and
second end portions, the fin members having first and second thermal transfer
surfaces, the first thermal transfer surface defining a first fluid
passageway, a first fluid
entering the first end portion from the U-shaped portion at a first
temperature and
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flowable along the first thermal transfer surface, the first fluid exiting the
second end
portion at a second temperature; and
c) a second fluid passageway having an inlet and an outlet, the second fluid
passageway being located in intimate contact with the second thermal transfer
surface,
the inlet being connectable to a source of a second fluid, the second fluid
entering the
inlet at a third temperature and flowable along the second fluid passageway,
such that
the first fluid when flowing along the first fluid passageway exchanges
thermal energy
with the second fluid flowing along the second fluid passageway, the second
fluid
exiting the outlet at a fourth temperature.
Accordingly in one embodiment of the present invention there is provided a
drainage
apparatus for use with a drain trap, the apparatus comprising:
a) a P-Trap having a drain portion being disposed orthogonal to the ground and
connectable to the drain trap and a U-shaped drain portion;
b) a heat exchange apparatus in fluid communication with the U-shaped portion,
the apparatus having a channel member having first and second thermal transfer
surfaces, at least one thermal transfer surface being uneven and defining a
first fluid
passageway for a first fluid received from the U-shaped portion; and
b) a second fluid passageway for a second fluid, the second fluid passageway
being located in intimate contact with the second thermal transfer surface,
the flow of at
least one of the fluids being disrupted such that the first fluid when flowing
along the
first fluid passageway exchanges thermal energy with the second fluid flowing
along the
second fluid passageway.
Accordingly, in another embodiment there is provided a heat exchange
apparatus, as
described in the embodiments above, for use with a drain trap of a bath tub or
a shower
tub in a household drainage system.
Accordingly, in another embodiment there is provided a turbulator for inducing
turbulent
flow in a fluid, the turbulator comprising: a hollow blade member having a
fluid inlet and
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a fluid outlet, and a fluid passageway for the fluid extending therebetween,
the fluid
passageway being configured to induce turbulent flow in the fluid as it flows
therealong.
Accordingly, in yet another embodiment, there is provided a heat exchange
apparatus,
the apparatus comprising: a plurality of turbulators for inducing turbulent
flow in a first
fluid, each turbulator having a hollow blade member having a fluid inlet and a
fluid
outlet, and a first fluid passageway for the first fluid extending
therebetween, the first
fluid passageway being configured to induce turbulent flow in the first fluid
as it flows
therealong; and a second fluid passageway for a second fluid, the second fluid
passageway being sized and shaped to receive the turbulators therein and
configured
to induce turbulent flow in the second fluid as it flows along the second
fluid
passageway.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the invention will become more apparent from the
following
description in which reference is made to the appended drawings wherein:
Figures 1A and 1B illustrate a household shower/bath system showing the
location of
an embodiment of a heat exchange apparatus;
Figure 2 is an exploded perspective view of an embodiment of a heat exchange
apparatus;
Figure 3A is a perspective view of a channel member of Figure 2;
Figure 3B is a partial cross-sectional view taken along line 3b-3b' of Figure
3 showing
two uneven thermal transfer surfaces;
Figure 4A is an end view of the channel member showing a single uneven thermal
transfer surface;
Figure 4B is a detailed view of a number of peaks and troughs of the channel
member
of Figure 4A;
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Figure 5A is a longitudinal cross section view of the heat exchange apparatus
showing
the location of end caps;
Figures 5B and 5C are end views showing respectively the first end cap and the
second
end cap located relative to the channel member;
Figure 5D is a cross sectional end view of the heat exchange apparatus with
the end
cap removed;
Figure 6 is a perspective view of another embodiment of a capillary heat
exchange
apparatus with end caps removed to show a channel member;
Figures 7A-7D are a number of cross section views of the channel member of
Figure 6
showing different locations of capillaries and double walls;
Figure 8 is an alternative cross section view of the channel member of Figure
6
showing the location of grey water;
Figure 9A and 9B are diagrammatic representations showing an end view
comparison
of a standard conduit with a heat exchange apparatus;
Figure 10 is a detailed partially exploded perspective view of an alternative
capillary
embodiment of a heat exchange apparatus;
Figure 11 is a partial cutaway view showing detail of the apparatus of Figure
10;
Figures 12A and 12B are respectively an end view and a perspective view of an
insert
showing circumferentially disposed hollow (capillary) fin members;
Figure 13 is a longitudinal cross sectional view of an embodiment of a partial
clam shell
and partial blister pack heat exchange apparatus located around a grey water
pipe;
Figure 14 is a cross sectional end view of a blister pack-type heat exchange
apparatus
located adjacent a grey water pipe;
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Figures 15A and 15B are cross sectional views showing a double wall bladder-
type
heat exchange apparatus and a blister pack heat exchange apparatus located
around a
grey water pipe;
Figure 16 is a cross sectional end view of an embodiment of a heat exchange
apparatus showing an arcuate insert and atmospheric vent;
Figures 17A and 17B illustrate a household shower/bath system showing the
location of
a heat exchange apparatus relative to a P-Trap;
Figures 18A and 18B illustrate a household shower/bath system showing the
location of
a check valve relative to the heat exchange apparatus;
Figure 19A and 19B is an end view and a perspective partial exploded view of
an
alternative embodiment of a heat exchange apparatus showing a one piece insert
having a multiple fluid circuit;
Figure 20A is a perspective partial exploded view of a heat exchange apparatus
showing multiple one piece inserts;
Figure 20B is an end view of the heat exchange apparatus of Figure 20A;
Figure 21A is a perspective exploded view of an embodiment of an alternative
capillary
heat exchange apparatus;
Figure 21 B is a side view of the heat exchange apparatus of Figure 21 A
Figure 21 C is a cross sectional view of the channel member of Figure 21A
showing
square top hollow fin members;
Figure 22A is an end view of round top capillary heat exchange walls;
Figure 22B is diagrammatic representation of a heat exchange apparatus showing
difference planes of flow for grey water;
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Figure 23 is a perspective view of an embodiment of a blade type heat exchange
apparatus with blade members removed;
Figure 24A is a perspective view of an alternative embodiment of a blade type
heat
exchange apparatus showing blades having surface patterns;
Figure 24B is a partial cross-sectional view of blade members of Figure 24A
showing
interdigitating surface projections;
Figure 25A is a diagrammatic representation of a hollow blade member showing
combined performance enhancement surface features in which GW is grey water
and
CW is cold water;
Figure 25B is a diagrammatic representation of the hollow blade member taken
along
lines 25B showing fluid flow patterns;
Figure 26 is a perspective, exploded view of an alternative embodiment of a
blade type
heat exchange showing blades having angled surface ridges;
Figure 27 illustrates a number of club grip type corrugated heat exchanger
piping;
Figure 28A is a side view of a blade member showing in solid lines a plurality
of angled
ridges on one surface and in phantom lines a plurality of angled ridges on
another
surface and illustrating criss cross patterns and contact points;
Figure 28B is a cross sectional view of the blade member taken along line 28B
showing
the location of ridges and recesses of two blade surfaces;
Figure 29 is a diagrammatic representation of a section of a blade member
showing a
centre spot weld, ridges, and crimped ends;
Figure 30A is a longitudinal cross section view of a double wall blade member
showing
atmospheric vents;
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Figure 30B is a cross section view of the blade member taken along 30B showing
the
double wall and surface textures;
Figure 31A is a diagrammatic representation of a hollow blade member showing
macroscopic and microscopic textures and fluid flow patterns;
Figures 32A and B is a representation of a golf ball showing alternative
icosahedron
dimple structure;
Figure 33 is a perspective partial cutaway view of a blade-type heat
exchanger;
Figure 34 is a detailed view of an end portion of the blade-type heat
exchanger of
Figure 33 showing the manifold and heat exchange wall details;
Figure 35 is a detailed side view of one end of the heat exchange apparatus of
Figure
33 showing ridges and recesses of blade member surfaces;
Figure 36 is a partially exploded view of a blade type heat exchanger showing
an
alternative orientation of the cold water manifolds;
Figure 37 is a perspective view of a large scale blade-type heat exchange
apparatus
housing;
Figure 38 is a perspective view of the heat exchange apparatus of Figure 3
with the top
removed to show the blade members;
Figure 39 is a side view of a large dimensioned blade member;
Figure 40 is a perspective view of an alternative design of a large dimension
heat
exchanger apparatus housing;
Figure 41 is a side view of an alternative embodiment of a vertical heat
exchange
apparatus;
Figure 42 is a longitudinal cross sectional view of the heat exchange
apparatus of
Figure 41 showing the location of a double slinky turbulator;
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Figure 43 is a detailed view of a section of the double slinky wire
turbulator;
Figure 44A and 44B are respectively a partial cutaway view and a detailed view
of a
double slinky wire turbulator;
Figures 45A, 45B and 45C are respectively a partial cutaway view and a
detailed view
of a mesh turbulator;
Figures 46A-46H illustrate a number of designs of compact heat exchanger
apparatus
comprising internally located wire turbulators or surface defined ribbed
turbulators;
Figure 47A and 47B are perspective view of respectively a smooth turbulator
and a
double sided ribbed turbulator;
Figure 48 is a diagrammatic representation of a system for controlling and for
monitoring heat exchange apparatuses.
DETAILED DESCRIPTION
Definitions
Unless otherwise specified, the following definitions apply:
The singular forms "a", "an" and "the" include corresponding plural references
unless
the context clearly dictates otherwise.
As used herein, the term "comprising" is intended to mean that the list of
elements
following the word "comprising" are required or mandatory but that other
elements are
optional and may or may not be present.
As used herein, the term "consisting of" is intended to mean including and
limited to
whatever follows the phrase "consisting of'. Thus the phrase "consisting of
indicates
that the listed elements are required or mandatory and that no other elements
may be
present.
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As used herein, the term "turbulator" when referring to either a surface or to
an insert
having a surface that acts as a turbulator, is intended to mean that the
surface has a
plurality of projections extending away therefrom. Surface turbulators and
inserted
turbulators are used to increase convenction rates and heat transfer
coefficients at heat
exchange surfaces in fluid passageways in order to provide high performance in
compact heat exchange assemblies, and to orientate fluids into a pre-defined
direction
often resulting in chaotic paths. Examples of types of turbulators include,
but are not
limited to, corrugations, peaks and troughs, nubbins, raised chevrons having a
gap
between, fish scales, raised zigzag moldings, meshes, criss cross oriented
wires,
porous materials, and the like. Turbulators may comprise uniform or non-
uniform
surface profiles, textures, open cell structures, and shapes. Porosity and
fluid
passageway geometry allow control of fluid flow via solid or semi-solid
mechanical
structures and may be constructed from laminate composites, molded parts, and
even
mesh of plastics, ceramics, metals or other materials.
As used herein the term `Yluid" is intended to mean gas or liquid. Examples of
liquids
suitable for use with the heat exchangers described herein include, but are
not limited
to, water, hydraulic fluid, petroleum, glycol, oil and the like. Examples of
gases include,
for example, combustion engine exhaust gases and steam.
The invention features a novel heat exchange apparatus in which hollow fin
members
or hollow blade members with or without surface patterns can be used to
promote
efficient thermal energy transfer between fluids across thermal energy
transfer
surfaces. The flow of fluids can be passive, i.e. by gravity or can flow under
the
influence of pressure, either above or below atmospheric pressure. The heat
exchange
apparatuses described herein are also self-draining. Moreover due to their
design, the
blade members can be located directly in a grey water pathway with or without
the use
of pre-flitration to remove particulate debris. In one example, the efficiency
of heat
recapture is 40-60% when compared to 25% heat recapture efficiency of
conventional
systems. To achieve this, in one example, we use a channel with plurality of
hollow
blades to move, by gravity, grey water along a pathway such that it exchanges
its heat
(typically about 40 C) to a source of cold water flowing through another
passageway
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located in intimate contact with the channel. In other examples, higher fluid
temperatures (>100 C) can also exchange their thermal energy to cold water so
as to
generate steam. The heat exchange takes place across a thin (typically from
about
1/1000 inch to about 1/5 inch thickness) double wall arrangement. Furthermore,
thermal energy transfer occurs along a significantly shorter pathway between
thermal
transfer surfaces when compared to thermal transfer across solid fins. The
cold water
is heated to produce warmed water, which may then be stored in a storage tank
or
communicated to a mixing valve in a shower or bath system. Advantageously, the
heat
exchanger apparatus is constructed from inexpensive materials and when
installed is
essentially maintenance-free. The grey water conduits (pipes) used are
standard 1.5 to
4 inch and are universally retrofittable into existing plumbing systems with
the minimum
of disruption to the household. The apparatus may also be connectable to
active heat
exchange apparatus such as, for example, a Peltier Module. The various designs
of
heat exchange apparatus will now be described in detail.
Referring now to Figures 1A and 1 B, an embodiment of a modular heat exchange
apparatus is shown generally at 10 in use with a household shower and bath
system
12. The household shower and bath system 12 includes a water heater 14, a hot
water
line 16, a cold water line 18, a warm water line 20, a mixing valve 22, a
shower head 24
and a drain trap 26. The hot and warm water lines 16, 20 are each connected to
the
mixing valve 22, the temperature of the water exiting the shower head 24 being
controlled by the user operating the mixing valve 22. The cold water line 18
is
connected to the heat exchange apparatus 10 and feeds cold water 25 (a second
fluid)
into the apparatus 10. The warm water line 20 is connected to the heat
exchange
apparatus 10 and the mixing valve 22. The drain trap 26 receives drain water
28 (so
called "grey water") (a first fluid) from the shower/bath tub and communicates
the drain
water to the heat exchange apparatus 10. After flowing through the heat
exchange
apparatus 10, the grey water 28 exits the household shower system 12 to a main
drain
(not shown). It should be noted that although an example of a household
shower/bath
system is illustrated, the heat exchange apparatus described may also be used
for
other applications that require heat exchange between two fluids. Furthermore,
it is to
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be noted that any of the heat exchangers described hereinbelow can also be
connected
to the system 12.
Referring now to Figure 2, the heat exchange apparatus 10 is described in more
detail.
Broadly speaking, the heat exchange apparatus 10 comprises a channel member 30
which has a first end portion 32 and a second end portion 34, and which
defines a first
fluid passageway 36 for the first fluid 28. The channel member 30 includes a
first
thermal transfer surface 38 and a second thermal transfer surface 40. At least
one of
the thermal transfer surfaces is uneven. In the example illustrated, both the
thermal
transfer surfaces 38, 40 are uneven. In the example shown, the first thermal
transfer
surface 38 is corrugated and defines a plurality of fin-like peaks (or blades)
42 and
troughs 44 that extend longitudinally along the channel member 30 between the
first
and second end portions 32, 34. Although the peaks 42 and troughs 44 are
disposed
substantially parallel to each other, it is to be understood that the peaks 42
and troughs
44 can be arranged in any manner. The first end portion 32 is connectable to a
source
of the grey water 28, which enters the first end portion 32 at a first
temperature T1 and
flows along the surface 38, exiting the second end portion 34 at a second
temperature
T2. A second fluid passageway 46, typically a cold water conduit, has a second
fluid
inlet 48 and a second fluid in outlet 50, and is located in intimate contact
with the
second thermal transfer surface 40 of the channel member 30. The second fluid
inlet
48 is connectable to a source of the second fluid (not shown), which enters
the inlet 48
at a third temperature T3 and flows along the second fluid passageway 46. The
grey
water 28 exchanges thermal energy with the cold water such that it exits the
outlet 50 at
a fourth temperature T4 as warmed water. The temperature of the warmed water
T4 is
greater than the temperature T3 of the cold water entering the inlet 48. The
warmed
water feeds into the warm water line 20 and may be mixed with hot water in the
mixing
valve 22.
The first and second fluids flow in a contra-flow manner through the heat
exchange
apparatus 10. It is also possible to have the fluids flow in a parallel flow
manner. The
first temperature T1 of the first fluid 28 entering the first fluid passageway
36 can be
greater than or less than the second temperature T2 of the first fluid 28 as
it exits the
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first fluid passageway 36. Similarly, the third temperature T3 of the second
fluid 25 can
be greater than or less than the fourth temperature T4 of the second fluid 25
as it exits
the second passageway 46. In the examples illustrated herein, the first
temperature T1
of the first fluid 28 entering the first fluid passageway 36 is greater than
the second
temperature T2 of the first fluid 28 as it exits the first fluid passageway
36. The third
temperature T3 of the second fluid 25 is less than the fourth temperature T4
of the
second fluid 25 as it exits the second fluid passageway 46. By way of example,
T1 is
typically 40 C for grey water (the first fluid), T2 is typically 30 C for grey
water exiting
the heat exchanger 10, T3 is typically 10 C for cold water (the second fluid),
and T4 is
typically 24 C for warmed water entering the warm water line 22 from the heat
exchanger 10. To measure the efficiency of the heat exchange apparatus, the
following
equation is used:
Effectiveness = Tcold out - Tcold in
Tgrey in - Tcold in
where T denotes temperature in C
At least one of the fluids flows through its respective passageway under
pressure, the
other fluid flowing through its respective passageway at atmospheric pressure.
Typically, the second fluid (the cold water) flows under pressure at
approximately 50 psi
along the second fluid passageway 46.
Still referring to Figure 2, the heat exchange apparatus 10 further comprises
an arcuate
piece 52, a first end cap 54 and a second end cap 56. A support member 58
interconnects the arcuate piece 52, the end caps 54, 56, and provides a
housing for the
channel member 30 and the second fluid passageway 46. The channel member 30
may optionally include a mesh filter 60 which lies snug against the channel
member 30.
The mesh filter 60 significantly reduces the amount of debris, such as hair,
soap scum
and other particulates, which would otherwise clog the channel member 30.
Referring now to Figures 3A and 3B, the channel member 30 is generally
elongate and,
when viewed in cross-section, is H-shaped. The channel member 30 includes two
sidewalls 62, 64 which form a boundary on either side of the channel member
30. It is
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to be understood that although the channel member 30 in this example
illustrated is H-
shaped, any cross sectional shape is possible. When connected to the drain
trap 26,
the channel member 30 is disposed away from a horizontal plane towards the
ground at
an angle of about 1 such that when the grey water from the shower drain
enters the
channel member 30 at the first end portion 32 it flows passively and by
gravity along the
first fluid passageway towards the second end portion 34. Two adjacent peaks
42a and
42b define one trough 44a located therebetween. A fluid convection promoter 68
(or
turbulator) is located at a trough base 70 and projects into the trough 44a.
The
convection promoter 68 is located on the first thermal transfer surface 38 and
increases
thermal exchange, across the surface 38. Located between an end peak 42c and
each
side wall 62, 64 is another convection promoter 68. The convection promoters
68 can
be in the form of a microscopic peak, although other promoters known to those
skilled
in the art can be used. The second thermal transfer surface 40 may optionally
include
a plurality of fin-like projections (or blades) 66, which extend away from the
surface 40,
as best illustrated in Figure 3B. In one example, the projections 66 may be
also be
corrugations similar in shape to the corrugations on the first thermal
transfer surface 38.
The cold water conduit (the second fluid passageway) lies snugly and in
intimate
contact with the projections 66 so as to provide highly efficient heat
transfer from the
first fluid passageway 36 to the second fluid passageway 46.
Referring now to Figures 4A and 4B, the second thermal transfer surface 40 is
smooth.
In this case, the second fluid passageway 46 is located adjacent the second
thermal
transfer surface 40 and includes a plurality of turbulators 72 located in the
second fluid
passageway 46. The turbulators 72 indue turbulence and establish shear forces
in the
second fluid as it flows through the second fluid passageway 46. A number of
turbulators designed for round pipe insertionare known to those skilled in the
art.
As best illustrated in Figure 4B, as the grey water flows along the first
fluid passageway
36 a rotational flow pattern is established, as indicated by the arrows,
between adjacent
peaks. This convective rotational flow pattern provides enhanced transfer of
thermal
energy from the grey water to the heat conductive peaks 42 and troughs 44 of
the first
thermal transfer surface 38 to the second fluid passageway 46 located adjacent
thereto.
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Delaminators (turbulators) can also be used to induce fluid rotation, or
laminar flow
disrupters (turbulators) may be used to enhance thermal energy transfers and
also to
manage fluid flow. Advantageously, turbulators also manage debris and reduce
its
accumulation in the first and second fluid passageways.
As best illustrated in Figures 2 and 5A through 5D, the first end cap 54 is
connected to
the first end portion 32 of the channel member 30, whereas the second end cap
56 is
connected to the second end portion 34. In order to aid flow of the grey water
along the
first fluid passageway 36 by gravity and to reduce "pooling" of water in the
apparatus,
the second end cap 56 is disposed at an angle away from a longitudinal axis 74
of the
channel member 30. The location of the second end cap 56 with respect to the
first
end cap 54 creates a deviation away from the axis 74. While this may be
acceptable to
some local plumbing regulations, it may be prohibited in others. In order to
circumvent
this problem, the first end cap 54 can be connected to the lower first end
portion of the
channel member 30 with the same deviation from the longitudinal axis of the
channel
member 30 such that the grey water would flow along the channel member at a
typical
angle of 1 away from the horizontal.
Referring now to Figure 6, an alternative example of a heat exchange apparatus
76 is
illustrated which comprises a non-H shaped channel member 78, the first and
second
end caps 54, 56, the cold water inlet 48 and the warmed water outlet 50. The
channel
member 78 includes a plurality of capillary hollow fin members 79 which define
wave-
like peaks 80 and troughs 82 extending along the channel member 78 between the
first
and second end portions 32, 34.
As best illustrated in Figures 7A through 7D, the hollow fin members 79
include a first
thermal transfer surface 84 located on an upper portion of a first wall 86
(adjacent the
grey water), the first thermal transfer surface 84 defining the first fluid
passageway 28
for the first fluid, and a second wall 88 located in intimate contact with the
first wall 86.
A second thermal transfer surface 90 is located on a lower portion of the
second wall
88. The grey water flows along the first fluid passageway 28 in contact with
the first
thermal transfer surface 84. A second fluid passageway 92 is in intimate
contact with
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the second thermal transfer surface 90. The second fluid passageway 92 is a
capillary
which carries the second fluid. The walls 86, 88 are generally constructed
from thin
sheet thermally conductive material such as, for example, aluminium, gold,
copper or
alloys thereof. Additionally, the second wall 88 is sandwiched between the
capillary
fluid passageway 92 and can allow venting to the atmosphere via an
interstitial gap
between the first and second walls 86, 88 in the event that the integrity of
the walls 86,
88 are compromised. It should be noted that although a double wall arrangement
is
illustrated, a single wall arrangement is also contemplated, such that the
capillary lies in
intimate contact with the second thermal transfer surface of the single wall.
The
channel member 78 is mounted on a support 94 that includes a number of
complementary posts 96 which extend into the space between adjacent peaks. As
described above for the heat exchange apparatus 10, the grey water flows along
the
first fluid passageway it exchanges thermal energy with the cold water flowing
along the
second fluid passageway. However, in this case the hollow design of the fin
members
79 allows heat exchange across a thin (typically from about 1/1000 inch to
about 1/5
inch thickness) wall arrangement, such that thermal energy transfer occurs
along a
significantly shorter pathway between the thermal transfer surfaces when
compared to
thermal transfer across solid fins as described above. The thin walls of the
heat
exchanger 76 improve performance. Various stiffeners such as, for example,
surface
adhesion, interlocking geometries, external supports, fasteners, internal ribs
and
chambers, as well as turbulators or combinations thereof, are used to allow
the use of
thin walls. Water hammer protection (not shown) can be built into the soft
zones of the
support 94 or the posts 96. Additionally, turbulators (surface or insertable)
may be
used with either of the first and second fluid passageways.
As best illustrated in Figure 8, instead of having a capillary fluid
passageway 92 for the
second fluid, the second fluid may flow against the lower portion of the
second wall 88
with the addition of turbulators 98 to provide forced convection by shearing
of the
second fluid at it travels in intimate contact with the second thermal
transfer surface. It
is also possible to have similar turbulators 98 on the first thermal transfer
surface, but
this may compromise the flow of the grey water. An additional advantage of
having
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turbulators 98 replacing posts 96 is increased strengthening of the channel
member.
Owing to the thinness of the walls of the hollow fin members, strengthening
members
such as the turbulators 98 may be necessary to maintain the structural
integrity of the
channel member. Grey water flowing along the channel member 78 fills the
troughs 82
to near the top of the peaks 80. Thermal energy is transferred across the
first thermal
transfer surface 84 to the second thermal transfer surface 90 via the first
and second
walls 86, 88 and to the cold water flowing in the second fluid passageway 92.
Referring now to Figures 9A and 9B, typically, grey water exiting the drain
trap 26 of the
shower or bath tub enters a cylindrical 2-inch drain pipe 70 and defines a
surface areas
of approximately 0.85 in2 at a flow rate of approximately 10L/minute. A volume
of the
grey water in the pipe 70 normally never contacts the sidewall of the pipe 70
and if
thermal energy is to be recaptured by heat exchange across the sidewall, its
transfer
will be largely inefficient. Advantegeously, using the channel members 30 and
78
described above, the grey water 8 flows along the first fluid passageway 36 at
the same
flow rate as with the pipe 70, but does so over the length of the channels by
contacting
the heat conductive peaks 42 and troughs 44. Thus, the distribution of the
0.85 in2 area
into multiple smaller area sections maximizes the heat transfer from the grey
water by
maximizing heat exchange contact area surfaces.
Referring now to Figures 10, 11, 12A and 12B, in which an alternative
embodiment of a
heat exchange apparatus is illustrated generally at 100. The apparatus 100
comprises
a circumferentially disposed channel member 102, two end manifolds 104, 106,
optional turbulators 108, and an outer sleeve 109. The channel member 102
includes a
plurality of hollow fin members 110 and a capillary cold water passageway 112,
which
lies in intimate contact with the second thermal transfer surface. A cold
water inlet 114
feeds cold water into the capillary 112 and warmed water exits the capillary
at an outlet
116. Grey water flows into the apparatus 100 via the manifold 104 and flows
over the
first thermal transfer surface of the channel member 102. The turbulators 108
not only
disrupt the flow of the grey water and create forced convention, but they also
maintain
the structural integrity of the hollow fin members 110. The turbulators can be
surface
turbulators or insertable turbulators. Water hammer protection (not shown) can
be built
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into the soft zones of the turbulators 108. A one-piece capillary insert 111,
as illustrated
in Figures 12A and 12B, may be inserted into the outer sleeve 109. The one-
piece
insert 111 includes the channel member 102 as described above. The turbulators
108
can also be inserted into the insert 111 to further enhance thermal transfer
as well as
enhance the structural integrity of the apparatus. The centrally disposed
turbulator 108
can be used in a configuration where the shaft of the element 108 is used to
fasten and
tighten the manifolds 104, 106.
Referring now to Figure 13, an alternative embodiment of a heat exchange
apparatus of
the present invention is shown generally at 200. Broadly speaking, the heat
exchange
apparatus 200 comprises a cold water fluid passageway 202, which has an
optional
fluid passageway sidewall 204 in double wall configurations that is made of a
membraneous material, which is pliable, yet resilient. The material can be
made from
pliable sheet material, such as, for example, but not limited to, gold,
copper, or
aluminium. The material includes at least one heat conductive surface 206
which is
located in intimate contact with a portion of a sidewall 208 of a grey water
conduit 210.
The conduit 210 has an inlet 212 and an outlet 214. The grey water enters the
inlet 212
at a first temperature T1 and exits the outlet 214 at a second temperature T2.
In this
embodiment, the fluid passageway sidewall 204 is spreadable over an area of
the
conduit sidewa11208. The membrane may be a single sheet of pliable material or
it
may be part of a bladder that is made of the same pliable material. The fluid
passageway 202 may be defined by the use of an inwardly directed force from an
external shell 218 that is located adjacent the sidewall 204. In the example
illustrated,
the shell 218 surrounds the conduit 210 and the sidewall 204. It is also
contemplated
that only a half shell located adjacent a lower portion of the conduit could
be used. The
shell 218 includes a plurality of inwardly directed projections 220, which
when pressed
against the membrane or bladder defines the fluid passageway 202, and act as
turbulators. The fluid passageway includes a fluid passageway inlet 221 and a
fluid
passageway outlet 223. The second fluid (cold water) enters the fluid
passageway inlet
221 at a third temperature and exits the fluid passageway outlet 223 at a
fourth
temperature. Examples of shells include, but are not limited to, clamshells or
blister
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packs. The pre-defined designs of the projections 220 can be used to imprint a
complementary design onto the membrane or bladder thereby define a fluid
passageway having an identical design as the clamshell or blister pack. In
single wall
configurations, the bladder or the blister packs are omitted, and the
passageway 202 is
defined directly by the shell 218.
Referring to Figure 14, an example of a blister pack type of shell 222 is
shown located
adjacent a heat conductive sidewall 224 of a grey water conduit 225. The
blister pack
222 includes a thermal transfer surface 226 which lies in intimate contact
with the
conduit 225. Although the example illustrated shows a grey water conduit, it
is to be
understood that this is an optional feature and that the grey water may flow
in direct
contact with the thermal transfer surface 226. A plurality of spaces 228
between
adjacent blisters 230 serves as the second fluid passageway for cold water to
flow
therealong. One or more of the spaces 228 may also comprise turbulators. The
blister
pack and clam shells can be positioned so that metallic surfaces in contact
with the
grey water conduit effectively extend with fin-like patterns into the cold
water
passageway.
Referring now to Figures 15A and 15B, the heat exchange apparatus 200 and the
blister pack 222 can be located around a grey water conduit. In the examples
illustrated, the conduit includes inwardly projecting square-shaped fins 232
and an
outer shell 234, which provides support for the components of the heat
exchange
apparatus. In one example, the bladder 204 lies snug against the outer wall of
the
conduit. In another example, the blister pack 222 lies in intimate contact
with the
sidewall 224. The blister pack 222 also defines the second fluid passageway. A
drain
hole 236 is located in the shell 234 to provide venting of the first and
second fluid
passageways away from the apparatus should either of the blister pack or the
bladder
rupture.
Referring now to Figure 16, an embodiment of a heat exchange apparatus is
shown
generally illustrated at 300 in cross sectional view. This heat exchange
apparatus 300
comprises a conduit 302 with an arcuate conduit member 304 and a fluid
passageway
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306. The conduit 302 has first and second ends 308, 310, and an arcuate heat
exchange plate 312. The arcuate heat exchange plate 312 has first and second
connecting portions 313, 314 that are sealingly connected to the respective
first and
second ends 308, 310 of the conduit 302. The heat exchange plate 312 has first
and
second thermal transfer surfaces 316, 318. An amount of grey water enters the
conduit
302 at a first temperature and contacts the first thermal transfer surface 316
and exits
the conduit 302 at a second temperature. Generally speaking, this embodiment
is
useful for grey water that covers the arcuate heat exchange plate 312 and
reaches a
depth of several millimeters in the conduit 302. A fluid passageway 320
similar to the
one described for the heat exchange apparatus 200 above can be used with this
embodiment. In this example, the fluid passageway 320 is in the form of a
bladder and
is located in intimate contact with the second thermal transfer surface 318 of
the heat
exchange plate 312. A cap 322, which is comparable to the shell described
above,
may be located snug against the bladder so as to form the fluid passageway
320. A
drain hole 324 is located in the cap 322 to drain water away to atmosphere in
case the
integrity of the bladder or the conduit 302 is compromised. The ability to
vent cold or
grey water is a requirement for certain plumbing standards to prevent mixing
of cold
water with waste drain water.
Referring now to Figures 17A, 17B, 18A and 18B, a household shower system is
shown
generally at 400 and includes a P-Trap 402. P-Traps are know to those skilled
in the
art. The heat exchange apparatus 300 as described above, would be ideally
suited for
use with any part of the P-Trap such that the heat conductive surface of the
heat
exchange apparatus could be located in intimate contact with a sidewall of the
P-trap
402. Furthermore, any part of the P-trap could be modified to include the heat
exchange apparatus 300, as described above. In this case, the grey water
exiting the
P-Trap would contact and flow along and against the heat exchanger plate 312.
Similarly, the heat exchange apparatus 10 and 76 could be used in place of
downstream portions of the P-trap. The heat exchangers as described above and
below may optionally include a check valve 403. The check valve 403 is of the
type
known to those skilled in the art. In the event of either a plumbing system
failure or
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maintenance, simultaneous to a grey water channel wall failure of the heat
exchanger,
the check valve 403 will replace or supplement the double wall membrane of the
heat
exchanger to protect the water supply circuit of the building where the
installation is
located.
As best illustrated in Figures 19A, 19B, 20A, 20B and 21, an alternative
embodiment of
a heat exchange apparatus is illustrated generally at 500. The heat exchange
apparatus 500 comprises a one piece insert 502 similar to the one piece insert
111
described above. In this embodiment, however, the insert 502 includes a
multiple
circuit 504 with a circumferentially disposed channel member 506 located
inside a shell
508. The shell 508 is larger than the radius of the insert 502 and defines a
void 510.
The void 510 may be filled with an insulating media such as air or some other
suitable
insulating material. The void 510 may also contain a fluid to which the insert
502 can
exchange thermal energy. The channel member 506 includes hollow capillary fin
members 512, each adjacent fin member 512 having located therebetween a post
514.
The insert 502 may include longitudinally disposed perforations 516, which
expose the
fin members 512 to fluid circulating within the shell 508. The shell 508
protects and
structurally reinforces the fin members 512 either by mechanical contact or by
additional components such as turbulator 526 located between the insert 502
and the
shell 508. Two end caps 520 are located at either end of the insert 502 and
seal the
insert 502, the fin members 512 and the void 510 in the shell 508. Tubing 522
and 524
carry the grey water and cold water via manifolds (not shown) into and out of
the heat
exchange apparatus 500. It is to be noted that either of the tubes 522 and 524
can be
individually connected in series or in parallel into one of the multiple
circuits 504 as well
as in contra flow or parallel directions so as to obtain the desired contra
flow or parallel
flow thermal performance characteristics of the heat exchange apparatus 500.
Additional turbulators 526, as described above, are located between the insert
502 and
the shell 508. The turbulators 526 create turbulence in all fluid passing
through the void
510 and promote heat exchange on the fin members 512 through the perforations
516.
Furthermore, the turbulators 526 also provide additional stiffening to the
heat exchange
apparatus 500.
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As best illustrated in Figure 20A and 20B, a plurality of inserts 502 may be
grouped
together into a larger heat exchange apparatus 528. This heat exchange
apparatus
528 is typically used when high volume, high flow and high performance is
required
such as for example in industrial applications. Typically, for these
applications rapid
heating and cooling is necessary for technical reasons, whether in grey water,
pharmaceutical processes, steam generation applications, food sterilization,
or cleaning
applications such as in farming. Using the apparatus 528, rapid and precise
heat
transfer from one fluid to another is achieved. The apparatus 528 can be
assembled
with bundles of the inserts 502, which are enclosed in sealed and pressurized
vessels
530. The vessels 530 include the multiple inserts 502 as well as multiple
turbulators
526. Fluid enters the void 510 via inlets 532 and exits via outlets 534. The
combination
of series and parallel connections of the grey water and cold water inlets and
outlets of
the fluid circuits provides improved heat exchange performance in a variety of
circuit
combinations and connections.
Built-in options may be included within any of the heat exchange apparatuses
described herein in order to increase overall sytem performance and
durability. These
options include thin wall elements; laminar flow disruptor elements; check
valve sytems;
one or more external level indicators; anti scaling capabilities such as, for
example,
mechanical devices and passage configurations to reduce scaling, anti-scaling
coatings, vibration, chemical, and electrical means; anti corrosion means such
as, for
example, electrical, chemical, anodic, cathodic, and coatings; and water
hammer
protection such as, for example, shock absorbers, flexible or relatively soft
and elastic
cold water circuit components. Additional features may include use of an
insulating
shell on the systems and subsystems. System leaks and malfunctions can be
detected
in a variety of ways using, for example, relative flow measurement and/or
pressure
transducers and gauges located at strategic points in the heat exchange
apparatus.
Extrudable capillary fin geometry, as well as flow disruptors and other
structural
elements can be made of glass or Pyrex. The heat exchangers may be self
draining in
both horizontal and vertical positions. Individual heat exchanger modules or
cylinders
or heat exchanger bundles can be positioned at the top or at the bottom of
larger
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vessels, such as with the vessels 530 described above, depending on heat
exchange
requirements in a given application. If electric power is required for
monitoring or control
equipment, power sources such as batteries, thermoelectric, or micro-turbines
can be
advantageously used in combination or alone.
Refering to Figures 21 A, 21 B, 21 C and 22A, an alternative design of a heat
exchange
apparatus is shown generally at 600. The apparatus 600 can be used in shower
applications and can advantageously be packaged into an enclosure of modest
dimensions, and easily inserted as a component of existing or new plumbing
systems,
with or without a check valve (not shown). The apparatus 600 comprises a tray
602, a
grey water area cover 604 and a channel member 606. Two end plates 608 each
include a grey water opening 610 are located at the ends of the channel member
606.
The channel member 606 includes an angled entry portion 612 and an angled exit
portion 614. The angled portions 612 and 614 are angled inwardly away from the
end
plates 608. Cold water is communicated into and out of the apparatus via cold
water
connectors 616 and flows along a cold water passageway 618. As it is generally
the
case with the other Heat Exchanger embodiments described above, grey water
area
cover 604 may optionally include internal auger guiderails (not shown) to
allow the
passage of a plumber's drain observation and cleaning tools inserted into
either of the
two grey water openings 610, without interfering with the flow of grey water
along the
channel member 606. The tray 602 includes cavities 620 and entry and exit
manifolds
622. Cold water turbulators (not shown) may be located in the cavities 620 and
inside
the cold water passageways 618 between the coldwater entry and exit manifolds
622.
The tray 602 and the cover 604 may be combined into a single piece if desired.
The
turbulators increase the thermal performance of the system by creating
turbulent flow
within the cold water passageways 618. As best illustrated in Figure 21 C,
when viewed
in cross section, the channel member 606 comprises a heat exchange wall 624 of
minimal thickness. The heat exchange wall 624 defines a plurality of troughs
626,
along which the grey water travels, and a corresponding plurality of square
topped
peaks 628. Located adjacent the heat exchange wall 624 is the cold water
passageway 618. The heat exchange wall 624 corresponds to the distance
travelled by
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the heat from each of the troughs 626 to each of the cold water passageways
618. This
capillary configuration provides exceptional heat exchange performance between
the
troughs 626 and the cold water passageway 618. The very small thickness of the
capillary heat exchange wall 624, combined with very large heat exchange
surfaces
can be achieved using specific geometries and high strength materials such as,
for
example, stainless steel, copper, gold, and the like, to form hollow fin
members, leading
to higher thermal performance than those obtained when solid material are
used. It is
well known in the art that thermal performance in relatively low temperature
cases, such
as with the heat exchange apparatuses described herein, thermal energy
transfer
performance depends on the following factors: heat exchange area, physical
material
properties (heat transfer rate), material thickness, flow turbulence
(convection) in each
fluid, and thermal gradient present between the two fluids. The heat exchange
apparatus 600 advantageously uses a corrugated foil to form the thin heat
exchange
wall surface 624 with a large surface area. A stiffening surface 630 is
attached to the
lower end of the troughs 626 at fastening locations 632 using fastening means
such as,
for example, brazing, seam welding or spot welding. This allows the location
of the
channel member 606 into a vessel that can be pressurized at will, while
maximizing
heat exchange surfaces of the fin members. -
Referring now to Figure 22B, the grey water passageway can enter the heat
exchange
apparatus at two distinct levels, as indicated by arrows 1 and 2 with respect
to grey
water channel planes 627, 629. Arrow 2 above the higher plane 629
advantageously
promotes debris passage in the grey water channel, albeit at the expense of
drainage
system slope disruption when installed in existing drainage systems such as
during
renovations. Also, the exit of the apparatus can be done in two different
configurations
with respect to the plane 627, the exit being either coplanar with the grey
water channel
or below, as illustrated by arrows 3 and 4.
Blade-type heat exchange apparatus
It is to be noted that in the heat exchange apparatuses 10, 76, 100, 200, 300,
500, and
600 described above, the grey water was described as the "first fluid" and the
cold
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water was described as the "second fluid". In the following embodiments, for
ease of
description of the heat exchangers, the cold water is now referred to as the
"first fluid"
and the grey water is now referred to as the "second fluid"
As best illustrated in Figure 23, we have now designed a so-called blade-type
heat
exchange apparatus, which comprises one or more hollow blade members 638, each
blade member having a first fluid (cold water) inlet 639 and a first fluid
outlet 641 and a
first fluid passageway 643 for a first fluid extending therebetween. The
hollow blade
members 638 are sized and shaped to be located in a second fluid passageway
645 for
a second fluid (grey water). The blade members 638 are configured to enhance
thermal energy transfer between the fluids as they flow along their respective
passageways. The blade members 638 can be each manufactured from suitably
formed thin sheet material, and spot or seam welded, or brazed and
individually
assembled. A plurality of hollow blade members 638 can be arranged
substantially
parallel to each other and assembled as a heat exchange apparatus in which the
blade
members 638 are connected together using fasteners 640. Each blade member 638
can be removed, tested for quality and re-assembled in the heat exchange
apparatus.
Also included is a cold water manifold 622 having a plurality of slots 623.
The blade
members 638 can also be assembled using mechanical components such as 0-rings
and gaskets, or they can be fastened by more permanent means, such as welding
or
brazing. In the latter case, the heat exchange apparatus can be made
exclusively from
welded or brazed thin sheet material, using well known high volume
manufacturing
techniques and quality control procedures in order to provide a high quality
heat
transfer and a durable system. Vents to the atmosphere may also be included in
the
assembly such as via an opening (not shown) adjacent to the manifolds 622.
Referring now to Figure 24A and 24B, the hollow blade member 638 includes a
plurality
of projections 649 located either on an inner wall surface 641 a or on an
outer wall
surface 645 or on both surfaces of the blade member 638. The projections 649
can be
located on a portion of the aforesaid surfaces or, as illustrated, can be
located along the
entire length of the outer surface 645 of the blade member 638. The
projections 649
can be any shape such as ridges, chevrons, pads, discrete nubbins and the
like.
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Furthermore, the projections 649 may themselves comprise well defined surface
roughness and additionally include microscopic projections extending
therefrom. The
projections 649 can be embossed on the surfaces 641 a or 645, or they may be
added
to a smooth surface of the blade member. Surface texture (roughness) increases
the
frictional forces acting between the fluid and the surface leading to higher
turbulence.
For household and industrial applications, the cold water passageway 643 of
each
blade member 638 typically operates under pressures of approximately 500-100
psi for
a duration of about thirty years, therefore it is desirable to reinforce the
blade members
638 to increase their lifespan. The projections 649 provide increased burst
resistance
to the passageways 643 by reinforcing and stiffeningthe blade members 638.
Furthermore, the reinforcement that the projections 649 provide allows the use
of very
thin walls, hence providing improved thermal exchange performance. Moreover,
the
projections 649 can be used to align the cold water passageways among
themselves
within the assembly, and with an outer shell 647. Advantageously, the
projections 649
control the fluid flow and enhance the thermal energy transfer between the
grey water
and the cold water by promoting and sustaining turbulent flow in the grey
water or the
cold water, or both, as they travel along their respective passageways.
Additionally, the
projections 649 enhance the thermal energy transfer between the grey water and
the
cold water by disrupting laminar flow and causing shear in the grey water, the
cold
water or both. The projections 649 can be incorporated to increase thermal
performance, by modifying and controlling the flow of either or both fluids by
a suitable
configuration, while determining, aligning, and maintaining the geometry of
the
individual heat exchange blade members as well as the geometry of their
assembly.
Additionally, the projections 649 may be extended from the blades 638 into the
top of
the grey water passageway (not shown) to help guide the passage of plumbing
tools
traversing the heat exchanger during maintenance, repair, or inspection
activity. Also,
alignment and sealing mechanisms and devices either directly or indirectly
involved
with the thermal energy exchange of the heat exchange apparatus may be used
and
are constructed of metallic or non-metallic materials. Various fastening
systems such
as welding, brazing, adhesion, cohesion, mechanical fasteners and seals and
the like
can be used to position, assemble and attach turbulator sub-system components
into
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the heat exchange apparatus. An additional advantage of the projections 649 is
that
they provide cold water anti scaling action and grey water anti clogging
action created
through suitable cold water and grey water water speed and water direction
management geometries, which in turn increases the useful life of the blade
members
and decrease maintenance needs.
As best illustrated in Figures 25A and 25B, the location of the projections
649 along the
surfaces of the blade members 638 causes induction of flow patterns as shown
by
arrows 642. The projections 649, in this case, ridges, are orientated in such
as manner
that when cold water passes through the blade member 638 it is de-laminated as
well
as rotated as shown by the arrows 642 so as to generally induce shear and
turbulent
flow in the cold water passageway 643. Similarly, in a contraflow
configuration, rotation
is also induced in the grey water channel by the same shaped projections 649,
as
illustrated by arrows 644, which enhances turbulent flow in the grey water.
The ridges
649 can be stamped into or out of the flat surface of the blade 638 or they
can be
added as sub-systems as described above.
Referring now to Figure 26, an embodiment of a high pressure blade type heat
exchange apparatus 800 is shown which comprises a bundle 801 of hollow blade
members 802 formed and stamped from stainless steel sheet and welded and
connected through a manifold to form the apparatus, which is then assembled
inside a
low pressure, atmospheric drain system envelope 803 through which grey water
804
flows by gravity. Each blade member 802 is made from a stainless steel sheet
that is
formed to obtain a hollow "flat" tubular shaped passageway where the general
shape is
other than cylindrical. Each blade member 802 includes a plurality of angled
ridges
805 or other tubulators located on at least a portion of a blade surface,
and/or as an
alternative turbulators may be inserted inside the blade or positioned outside
the blade
as a discrete mechanical component.
Referring now to Figures 27, 28A and 28B, it is possible to increase the
performance of
the blade type heat exchange apparatus described herein by using blade
members,
which are based on cylindrical, corrugated heat exchanger piping (also known
as "club
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grips"). As illustrated, a number of designs of "club grips" are known in the
art and have
wall exchanger surface dimensions that are maximized by the surface patterns.
The
patterns provide internal and external helical or "threaded screw motion" of
the fluids
resulting in fluid rotation. However, club grips lack the ability to maximize
fluid shear
and fluid turbulence. As best illustrated in Figure 28A and 28B, our blade
design is
based on a flattened club grip and provides inwardly disposed projections 810,
which
project into the cold water passageway 806, and outwardly disposed projections
812,
which project outward, typically by stamping during the manufacturing process,
from flat
walls 814, and which provides unexpectedly high chaotic blade passageway
geometry,
leading to high levels of shear and turbulence generated in the displaced
fluids. Seam
welds 816 are located along the length of the blade member 802. Additional
indentation shapes such as sharp bends and corrugations are also permissible,
as are
additional components (not shown) that can be welded onto either one or both
sides of
the originally flat and smooth heat exchanger walls (or by a combination of
both) in
order to delaminate and agitate the flow (i.e. induce shear and turbulence) of
cold water
flowing in the cold water passageway 806, as well as grey water flowing
outside the
blade member 802 and in contact with the outer surface of the blade member
802. It is
to be noted that the chaotic helical cross flow motion of fluids is obtained
in the
pressurized fluid, such as the cold water flowing in the cold water passageway
and also
in the atmospheric fluid, such as the grey water flowing externally of the
blade member
802. It is to be noted that the helical "club grips", typically made from
copper tubing,
and other similar style "round" tubing may also be employed in the high
pressure
apparatus 800, whether straight or with 90 degrees bent ends, in place of the
"corrugated flat wall" stainless steel hollow blade members. Additionally,
turbulators
can be inserted into the blade members 802.
It is known that greater thermal transfer performance and ease of
manufacturing are
obtained by using a thin formed sheet material in the manufacturing process of
the heat
exchanger components. Using thin wall stainless steel composite sheets of
approximately 0.015" to 0.035" thicknesses in heat exchanger apparatuses
provides
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low resistance to burst due to possible excessive high internal cold water
pressure,
such as those commonly used in household or industrial plumbing systems.
Referring now to Figures 28B and 29, an example of a stiffened geometrical
heat
exchange blade member, which includes fasteners 820 to maintain the structural
integrity of the blade member. It is therefore useful to use geometries of
wall stiffening
corrugation as well as fasteners 820 where they can self reinforce the
structure of the
pressurized cold water passageway. The fasteners 820 may be rivets, adhesives,
or
seam welds 816, as described above, as well as spot welds. In order to
maximize
thermal energy transfer as well as structural parameters, the internal
projections 810
and the external projections 812 with respect to the originally flat blade
surfaces 814
and multiple blades located together may intimately contact each other for
added in a
fastened confirmation structural stability. The blade members 802 can be
manufactured by stamping, bending and crimping an originally flat metal sheet.
This
can be advantageous when compared to using relatively slow linear welding to
produce
the seam weld 816. It is possible to use a combination of high speed edge
crimping
methods and tools to produce crimped areas 824 in the sheet 814. Methods and
tools,
such as those used to produce canned goods in the food industry can be used,
with the
use of optional adhesives or sealants to ensure seal intergrity where
required. One
such particularly useful technique, when long and straight seams are
fabricated, is
named "Swage Roll", in which the assembly of two sheets of metal is done by
using
compression wheels that shape and form a sealed seam between the two sheet
metal
surfaces. Progressive dies are also used for even faster forming and sealing
assembly
of such parts.
Double wall construction
Cross-connection of plumbing devices is ruled by strict, but variable, local
regulations,
where grey water and fresh cold water are present within the same heat
exchanger
apparatus. Universally, a double wall design is preferred over any other
protection
means to prevent fresh water contamination by grey water in the event of
system
failure, such as if the heat exchanger wall is ruptured or pierced.
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Referring now to Figure 30A and 30B, for single walled construction of a
hollow blade
member, that is, one without a lining such as a bladder, the external wall
surfaces 840
and the internal wall surfaces 842 are the thermal transfer surfaces of the
blade
member and provide two work surfaces. For the double wall blade construction,
four
heat exchange "work" surfaces are available. In the double wall construction,
as
illustrated, the internal wall (bladder) 850 includes an inner thermal
transfer surface 852
and an outer thermal transfer surface 854, and the outer wall includes the
internal wall
surface 842 and the external wall surface 840. An inter-surface space 856 is a
void
located between surfaces 842 and 854. The space 856 creates the separation
between the blade surfaces in the double wall configuration, and allows
atmospheric
venting via a vent 860. The bladder 850 optionally includes a sealed wall
overlap
portion 862 located adjacent the vent 860. The overlap portion 862 is sealed
using a
weld or adhesive. The bladder 850 further includes a cold water inlet 864 and
a
warmed water outlet 866. The bladder 850 is contructed of a relatively
flexible, possibly
pre-crushed and later pressure expanded, micro-corrugated, folded, ribbed or
patterned
material, with a typical wall thickness of between 0.001 inch to 0.015 inch. A
metallic
material is preferred, but other wall compositions are contemplated. As best
illustrated
in Figure 30B, the double wall configuration includes macroscopic peaks (or
ridges) 812
and a macroscopic recesses 810. Microscopic textures 844a and 844b are located
on
respectively the external and internal surfaces 840 and 842, and microscopic
textures
845a and 845b are located respectively on the external and internal surfaces
854 and
852. The microscopic textures provide additional surface turbulence to the
fluids in
motion.
The shell 802 of the blade assembly is essentially the same as in the single
wall
construction described above except for the fact that a plurality of
atmospheric venting
ports 860 are present in order to immediately evacuate any fluid penetrating
into the
defined inter-surface zone space 856. Leaking fluid immediately evacuates to
the
atmosphere either by gravity or by water pressure, whichever is greater, and
depending
on the origin of the leak. Leaking fluid evacuation is, however, increased by
the
textures described above. The inner pressure of the cold water compresses the
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bladder 850 with great force against the pressure bearing surface of the
external shell
802 to provide acceptable heat transfer rates between the grey water and cold
water. A
suitable thermal paste or porous filler material may be optionally used to
fill the inter-
surface zone space 856 to further enhance the thermal transfer rate.
Blade surface dimensions and shapes, areas and thicknesses, wall and surface
compositions and the nature of the material used to construct the blades, as
well as
surface treatment, macroscopic and microscopic surface shape and texture, all
determine the blade's ability to transfer heat and become non-adhesive, or
self-
cleaning. Additionally, non adhesion of dirt, soap, scum, hair and debris to
all heat
exchanger walls and surface features, can be controlled by fluid flow
management by
fluid velocity and surface turbulence control, as well as chemical anti-
fouling and
surfaces geometrical self-cleaning properties.
Referring again to Figures 25A, 25B, 30A, 30B and 31A, blade wall surface
geometry
controls and generates both deep (macroscopic) and surface (microscopic)
directional
turbulence mechanisms in given fluid dynamic conditions, resulting in combined
and
mutually reinforced convection patterns 642, 644, and 858, which enhance fluid-
to-fluid
heat transfer rate and perfomance. The increased heat transfer rate is
obtained by the
sum of a surface (or microscopic) fluid velocity caused by microscopic fluid
surface
textures 844a, 844b, 845a and 845b, which act as turbulators, on the heat
exchanger
walls as well as those turbulences created macroscopically as shown by the
convention
patterns 642, 644. The microscopic textures 844a, 844b, 845a and 845b are used
to
further delaminate the fluids circulating within the larger internal and
external
projections (ribs or ridges) 810, 812. A variety of microscopic and
macroscopic shapes
and textures are contemplated and may be combined to achieve maxmimum
turbulence. Within the space 856, the textures 844a, 844b, 845a and 845b are
used to
increase atmospheric venting efficiency, by providing an easier path to
eventual leaks
to the atmospheric vents 860.
Referring again to Figure 30B, 31A and now Figures 32A and 32B, different
patterns
and strategies can be used or combined on different sections of the blades as
well as
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individual fins, as described above, to maximize heat transfer rates for the
whole blade
assembly. In one example, a "golf ball icosahedron" surface pattern 832 in a
specific
location, such as on the nose of the external surface 840 of the blade, can be
used to
greatly reduce the accumulation of material, such as hair, at this
particularly critical
location.
Blade member design variations
It should be noted that the wall materials, shapes, thicknesses, widths and
heights,
surface textures and cross sections of the blade members and of their inner
components do not need to be symmetrical, fixed or constant in any manner with
respect to given geometrical axes of the assembly. For example, it is possible
to use a
blade with a large "front-end" and a slimmer "tail-end", in order to precisely
control heat
transfer surface dimensions and corresponding heat transfer rates between two
fluids in
cross-flow configurations. Variations where the effective cross section and
the height
and width of a blade or inter-blade spacing varies according to a mathematical
function
along the length of the blade or blade bundle assemblies are also contemplated
to
further enhance performance.
One of the advantages of the blade assembly is that whole assembly or even an
individual blade can be removed for cleaning, inspection and maintenance and
replaced if necessary. Moreover, the grey water can flow unfiltered along its
passageway. Specialized cleaning tools such as wire brushes or enzyme or
bacteria
based solutions, as well as chemical cleaners, or combinations thereof can be
periodically applied via the floor drain of the shower in order to dissolve
any dirt
accumulated over time on the heat exchanger grey water walls within the
drainage
system in order to maintain optimal said grey water flow characteristics and
thermal
transfer rates of the system, without affecting the environment or the
drainage
components in any significant matter. A strainer located at the grey water
floor drain
will also advantageously reduce debris entering the drain.
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Referring now to Figures 33, 34, and 35, a plurality of blade members 802 are
illustrated for use in a blade-type heat exchanger 868. The blade members 802
are
located in a housing 870 in which a lower portion 874 of the housing 870 is
optionally
open to allow atmospheric venting in double wall configurations. The of the
manifolds
622 are located substantially lower than the lower plane 627 of the grey water
passageway and are also optionally open to allow atmospheric venting. The
blade
members 802 are located substantially parallel to each other with gaps 876
between
each blade 802 which define a grey water passageway 847. In the embodiment
shown,
each blade member 802 has first and second walls 853 and 855, each with an
inner
thermal transfer surface 849 and an outer thermal transfer surface 851. Each
wall 853,
855 includes a plurality of ridges and recesses 844, 845 located thereon. As
illustrated,
the ridges and recesses 844, 845 are disposed diagonally relative to a
longitudinal axis
878 of the blade member 802 in one direction along the first wall 853 and
disposed in
opposite directions along the second wall 855 relative to the first wall. This
arrangement of ridges and recessed defines a "criss-cross" pattern, when
viewed from
the side in which a central cross area 857 is a location where opposing ridge
of
opposing inner thermal transfer surfaces make contact. Although not
illustrated, it is to
be understood that similar ridges and recesses may also be located in the grey
water
passageway. This alternating pattern of ridges and recesses induces high
levels of
shear within the fluids leading to rapidly developing turbulent flow
conditions in both the
cold water and the grey water by causing cross flow near or at the central
cross area
857, and on the planes located in the centre of the fluid passageways.
When the ridges and recesses 844, 845 are disposed diagonally, the relative
"criss
cross" configuration of the ridges on the walls of the blade members causes
high levels
of fluid shear, turbulence and cross flow within both the grey water and the
cold water.
However, it is to be understood that the ridges and recesses may be orientated
at any
angle relative to the longitudinal axis of the blade member, and may also
interdigitate,
or contact with each other at the central cross area, or they may be spaced
apart from
each other. In the example shown, the manifolds 622 for receiving the cold
water are
disposed generally orthogonal to the longitudinal axis 878 of the blade
members and
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downwardly away from the longitudinal axis, as best shown in Figure 33. In
this
example, the housing 870 together with the plurality of blade members 802 can
be
located in a tray 879 through which the grey water is flowing or the blade
members 802
can be manufactured as a unitary body with the tray located near the lower
portion of
the blade members 802. The grey water passageway 847 dimensions will depend
largely on the nature of the debris that is expected to be found in the grey
water as it
flows along the passageway 847 as well as on the fluid characteristics, such
as volume,
velocity and viscosity, expected in normal operating conditions also in order
to optimize
heat exchanger performance. A screen (not shown) can be used over the entrance
to
the grey water passageway 847 to prevent debris from entering the grey water
passageway 847. The screen can be located before the P-trap in a househould
shower/bath system. Moreover, the shape and location of each blade member 802
can
be changed to allow passage of a variety of debris types and fluid
hydrodynamic
characteristics. Thus, the grey water flowing along its passageway 847
contacts the
outer thermal surfaces of the plurality of blade members 802 such that
turbulence is
induced in the grey water, while simultaneously, turbulent cold water moving
along the
cold water passageway contacts the inner thermal surface thereby allowing for
efficient
thermal energy transfer across the walls of the blade members 802.
Ridges can be evenly spaced and shaped (depth and 3D forms) or follow a
pattern
defined mathematically along the blade walls, to increase blade surfaces and
generate
turbulent flow for various grey water and cold water flow conditions, thereby
maximizing
heat transfer. Fluid shear inducing ridges may be located at the bottom of the
grey
water passageway 847. Additionally, scale-type/shaped ridges can be used to
create
turbulent flow at the bottom of the grey water passageway 847, with a reduced
risk for
clogging. The same scales structure may be useful for location on the
periphery of
vertical heat exchange embodiment, as described below.
In the example illustrated in Figure 36, a bottom tray 880 is designed to
receive a
plurality of the blade members 802 in a pre-defined grey water passageway 881.
In the
example illustrated, the manifolds 622 are disposed upwardly away from the
longitudinal axis 878 of the blade members 802. This design aids the location
of the
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blade members 802 into the tray 880. This design is particularly well suited
large
laundry facilities such as those used in hospitals where a large of volume
grey water is
generated and flows in open channels when discarded at high temperatures. The
heat
exchangers of this design can be easily retrofitted into the existing plumbing
and easily
maintained and cleaned by lifting the blade member assemblies from the grey
water
passageway.
As best illustrated in Figures 373 to 40, the scale of the design may be
increased
substantially to include a plurality of blade members 882 of larger
dimensions, namely
in increased height dimensions leading to a further theorectical increase in
convective
heat transfer performance. A housing 884 is designed to accommodate the larger
blade members 882 and includes inlet and outlet grey water pipes 885, 886 and
inlet
and outlet cold water pipes 888, 890. The housing 884 includes a removable
upper
portion 892, which allows for easy access to the blade members 882. Referring
now
to Figure 39, the larger dimension blade member 882 include a plurality of
ridges and
recesses 894, which cover substantially the entire surface areas of each inner
and
outer sidewall of each blade member. For ease of illustration, only one outer
sidewall is
shown in Figure 46. As above, the criss-cross pattern of ridges (ribs) causes
shear and
turbulence in the flow of both the grey water and the cold water traveling
along the
internal and external portions of the blade. The pattern of ridges may include
other
previously mentioned shapes and may comprise combinations of them. The
orientation
of the grey water flow may be orthogonal to the flow if the cold water as is
illustrated by
the location of the grey water inlet and outlet pipes 885, 886 in Figure 40.
Additionally,
a plurality of spot weld points 896 and/or seam welds 898 are located to
fasten and seal
each sidewall of the blade members together. If a double wall design is used,
the
welds can pass through the opening in the bladder, which is sealed around the
punctured holes to maintain integrity of the double wall. Additonal features
of the
larger blades 882 include a plurality of flow management disrupters 899
located along
the edges of the blades 882.
In the previously described examples of the blade-like heat exchange
apparatus, the
manifolds are disposed downwardly away from the longitudinal axis 878 of the
blades
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to facilitate maintenance. This design is for use in household shower
arrangements in
which water typically drains at 10 litres/hour. For commercial applications,
however,
the manifolds may be disposed upwardly away from the longitudinal axis 878 of
the
blades. In larger applications, the larger blades are rigidified by welds and
can also
provide a double wall arranagement. The bladder is punctured and sealed around
each
structural weld. Moreover, if required, a section of the blade can be enlarged
by adding
additional sections of blade thereto. The additional blade sections can be
embossed
with flow disrupters. Alternatively, one can use a turbulatorinsert to induce
flow
turbulence inside the blades.
Referring now to Figures 41, 42, 43, 44A and 44B, another example of a heat
exchange
apparatus is shown generally at 900 and is particularly useful, but not
limited to
applications when used in a vertical orientation, that is, the apparatus is
disposed
generally orthogonal to the ground. In this design, a housing 902 is generally
tube-like
and includes a central grey water conduit 904, around which is disposed a cold
water
passageway 906 having an inlet 908 and an outlet 910. The cold water
passageway
906 includes a double "slinky" turbulator 912 which is modeled on the wire
"slinky"
children's toy, which efficiently generates shear forces within the fluid when
the slinkies
are arranged in a clockwise and counter clockwise configuration producing a
criss cross
pattern such as the one illustrated. Also, slinkies are highly flexible and
will allow the
heat exchange apparatus to be used in locations that require bending of the
grey water
and cold water passageways. One wire of the slinky 914 is coiled around the
grey
water passageway in clockwise orientation and the other wire 916 of the slinky
is coiled
in a counter clockwise orientation relative to the longitudinal axis of the
grey water
conduit 904. As in a hollow blade 802, 638 or 882 the "double helical" criss
cross
arrangement of the two slinky wires creates a turbulator and promotes high
turbulence
in the cold water flowing downwardly or upwardly such that the cold water is
constantly
sheared all within a single cavity located around the grey water passageway,
such as
that described for within the blade member 802. Additionally, where each of
the slinky
wires 914, 916 crosses each other, a cross area 911 is formed which is similar
to the
central cross area 857 described above for the ridges 844. Cold water when
following
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the path defined by the slinky wire 914 travels in one direction, and
simultaneously
when follows the path defined by the slinky wire 916 travels in an orthogonal
direction,
very high shear and turbulence is induced within the cold water passageway
906.
Since this highly turbulated cold water is trapped in the cavity between the
housing 902
and the grey water conduit 904, highly efficient heat exchange occurs between
the
optionally smooth thermal transfer surfaces of the conduit 904. Again, the
shearing
effects is similar to the one that is caused by the criss cross surfaces of
the design as
described above. This heat exchange design advantageously allows the design of
compact and pressure self supporting heat exchange apparatuses, which can be
used
either with the single wall configuration as described or with a bladder to
provide the
double wall capability. For increased heat exchange performance, a turbulator
108 can
be located inside the grey water passageway 904.
Referring now to Figures 45A to 45C, a mesh type turbulator 918 is shown in
the heat
exchanger. The mesh type turbulator 918 includes a plurality of criss crosses
911,
which are defined by a first plurality of clockwise helically orientated wires
and a
plurality of other helical wires disposed counterclockwise to the first
plurality of wires.
Although not illustrated, the mesh may also include a plurality of
orthogonally orientated
wires. The turbulator mesh can comprise of a variety or a combination of shear
inducing short path turbulent flow inducing surfaces such as, but not limited
to,
perforation open cell porous medica, molded, composite, stacked, slit,
interdigitated,
semi-rigid and symmetrical, textured elements. As described above, turbulators
may be
inserted in the grey water passageway or also in the cold water passageway.
An alternative to the double helical wire criss cross turbulator is a double
slinky wire
criss cross turbulator which consists of an insertion of a single clockwise
slinky wire into
a counter-clockwise patterned corrugated tube (club grip) or even into an
axial internal
finned tube or any other criss cross generating wire pattern.
Compact heat exchangers
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As best illustrated in Figures 46A to 46H, and 47A and B and 51, a compact
heat
exchange apparatus 1000 is a generally arcuate blade, where criss cross
turbulator
1001 is located in a cold water passageway or could be imprinted on the
surface of the
blade as described above for the other embodiments. The criss cross turbulator
1001
includes a series of helically and diagnonally disposed ribs 1006 and 1006.
The suitably dimensioned blade can be located inside a tubular pipe 1002 for
heat
exchange of calibrated or known volumes of grey water and cold water. The heat
exchange apparatus 1000 can also be located externally of the tubular pipe
1002. In
another example, the tubular pipe 1002 may be manufactured such that the
arcuate
heat exchange apparatus is integral with the pipe sidewall.
The arcuate blade heat exchanger apparatus 1000 can be used singly for
applications
in which a small volume of grey water is traveling along the pipe 1002 and
located
adjacent the area of the pipe where heat is to be exchanged. The arcuate
design of the
heat exchange apparatus means that multiple arcuate heat exchange apparatuses
can
be used to fully or partially encase the pipe 1002. Two or three or more
arcuate blade
heat exchange apparatuses 1000 can be used to fully encase the pipe 1002.
Also, if
the arcuate blades are located inside the pipe, the arcuate blades are
typically
constructed from metal with the turbulators 1001 located on one or both sides
of the
blade. If located outside the pipe, the blade is manufactured with metal on
one side and
the turbulators 1001 on one or both sides or inserted. Metal surfaces on both
sides of
the arcuate blade along with turbulators is a favoured construction for the
blades.
Sections of the compact designs are particularly useful for drain pipe heat
exchange
applications where drains are installed in a position other than vertical
relative to the
ground, and where one side of the pipe carries the energy to be exchanged.
Although in the examples described above, hollow, planar blades and hollow
arcuate
blades have been described, it is to be understood that the blades can be of
any three-
dimensional shape, such as cylindrical, conical, triangular, disk-like, and
the like.
Moreover, we also contemplate that planar hollow blades having surface
projections
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and recesses can be formed into a tube, the tube being optionally open along
the
longitudinal axis in order to be attached and clamped onto a central grey
water drain.
Referring now to Figure 46, a control system 700 may be used to monitor or to
control
the function of any of the heat exchange apparauses described herein. This is
particularly useful if the heat exchange apparatus is to be imbedded in a wall
or behind
an inaccessible structure. Moreover, if multiple heat exchangers are being
used
throughout a building, the ability to monitor the functions such as the
performance or
the energy transfer of the individual heat exchangers is advantageous. Thus,
the
system 700 may include a unidirectional or a bi-directional data transmission
and
communication, data acquisition function. The physiochemical properties of the
fluids
flowing in the heat exchangers can be monitored by the control system 700 and
any
changes to such can be monitored and a user alerted if any deleterious changes
occur.
This is particularly useful in heat exchangers that are used in the food,
pharmaceutical,
farming and water treatment industries. The control system 700 is constructed
and
programmed, and can be a wireless system, as well as conventional wire
assisted
system or alternatively, a combination of both and individually embedded or
externally
integrated to one or more heat exchanger systems. The system 700 can be
manually
operated, or computer controlled using telemetric applications involving well-
known
standard process operation parameters measurement, analysis and data
acquisition at
strategic locations such as, but not limited to entry and exit points.
Additional
parameters that can be measured and monitored include fluid viscosities, fluid
temperatures, fluid pH, fluid hardness, fluid ppm data, fluid mineral and
chemical
content, fluid lighting and imaging, fluid chromatography, fluid collection
and sampling,
fluid aeration, fluid velocity and flow rate, fluid pressure, fluid
turbulence, heat
exchanger sub-systems and overall sytem integrity and malfunction detection,
heat
exchanger system overall performance, heat exchanger instantaneous workload as
well
as efficiency computations. Additionally, rather than measuring within the
fluid or
acting upon the fluid, measurements and monitoring can be carried out within
the
system and sub-system components such as the heat exchanger walls, discrete
system
components, nozzles, sensors, actuators, fluid passageways, intersticial wall
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components, additional sub-systems. Fluid physical properties can be
monitored, data
acquisition can be made, and modifications to the heat exchange system
operation can
also be made. Such modifications include, but are not limited to, activation
of sensors
and actuators, as well as passive component temperatures, vacuum levels,
pressure
levels, vibration, moisture as well as other process related operating
parameters related
to the integrity and the performance of the heat exchanger system and other
sub-
systems. Manually operated, or computer controlled process control
applications can
include the operation and actuation of valves and sensors in order to modify
working
parameters of the heat exchanger system as well as actively or passively
modifying the
fluid physical properties. Also, the system 700 can maintain or optimize the
operation of
individual or remotely located heat exchange apparatuses in a larger heat
exchange
circuit by varying the individual workload or maintenance requirements over
time, or by
modifying the fluids for a subsequent process in terms of physical or chemical
property
requirement.
In addition to monitoring the heat exchange apparatuses, it is possible to use
the
system 700 to monitor and compute tariffs and fees based on heat exchanger
workload
and efficiency or other measurable physical workloads performed by the systems
over
time. Energy savings provided by the heat exchanger and peripheral systems can
be
evaluated, charged and billed to the user.
Other Embodiments
From the foregoing description, it will be apparent to one of ordinary skill
in the art that
variations and modifications may be made to the invention described herein to
adapt it
to various usages and conditions. Such embodiments are also within the scope
of the
present invention.
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