Note: Descriptions are shown in the official language in which they were submitted.
CA 02533960 2006-01-11
Field of Invention
This invention relates to the field of wind powered electrical generators, and
in
particular, it relates to a method and system for efficiently harnessing large
cross-
sectional areas of wind and improving the power conversion possible there-
from.
Summary
In machines which harvest the power of the wind, it is common practice to
employ a
rotor upon which are affixed blades, buckets, paddles, vanes or other such
appendages so pitched thereupon that when subjected to a wind current, the
continuous molecular collisions between the air-mass and commonly pitched
appendages results in deflection and rotation of the rotor to which they are
attached.
It is appreciable, however, that while appendages responsible for causing
rotor
rotation are designed to be as streamlined a flow obstruction as possible, and
may
even afford airfoil-induced speed beneficiation, that a sizeable component of
the
wind's available kinetic energy is nevertheless unavailable to the rotor of
prior art
systems of this type, being: carried away post-rotor-impingement by the re-
bounding
molecules of air; consumed by the replenishing wind-mass doing work to remove
the
air molecules slowed down during the deflection process; not used at all while
traveling straight through the area scribed out by prior art rotors occupying
but a small
percentage of the usable wind cross-sectional area; is lost to machine
friction in
support of driving rotors at 900 to the applied force (wind), or is otherwise
lost through
separate mechanical linkages to an alternator for purposes of electrical work
generation. Also, rotor speeds of prior art wind turbines are limited to
benefit only
from wind passing through the region scribed out by the maximum diameter of
the
rotor 'blades'. It is worthy of mention too that while locating wind-powered
electrical
generating machines of the 'bladed-rotor' style (typically associated with the
term
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'wind-farms') in areas of highest wind speeds benefits their output power
capability,
that these generally high-ground areas coincidently tend to be the nesting
grounds of
eagles, falcons and other endangered bird species. Birds flying too close to
prior art
wind turbines risk life-threatening injury through the potential for fatal
collision with the
moving rotors of such machines.
I have found that the disadvantages of prior art wind powered electrical work
generating machines may be overcome by application of the presently disclosed
invention which achieves speeds of operation not limited by the diameter of
its rotor
leading to higher work output capability through its ability to allow the
harvesting of
wind-power from large cross-sectional areas of wind, and optimization of the
pressure
differentials realized across first working fluid pressure amplification
segment
featuring no moving parts, second variable orifice expansion nozzle(s)
responding
proportionally to wind pressure, third high efficiency disc turbine (1)
optimally
designed for low-pressure (wind) operation, fourth divergent exhaust channel
beneficial to a lower pressure in the disc turbine's discharge stream, and
fifth 'wind-
turbine' exhaust induction (entrainment) into separate high-speed (low-
pressure)
wind-channel air stream(s) also offering pressure differential beneficiation
across the
disc turbine with no moving parts. Also, since the currently disclosed
invention has no
external moving parts (other than generally slow-motion turning with changes
in wind
direction in the case of self-guiding embodiments of the invention) it would
be a
benign replacement for prior art externally rotating machines in areas of
endangered
bird-species sensitivity offering improved work output.
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Detailed Description
In drawings illustrating embodiments of the invention, Figure 1 is a side
elevation view
partly in section depicting a stationary embodiment of the invention. Figures
2a, 2b,
and 2c are side elevation views of a 'Wind-Wall' approach extrapolating on the
stationary embodiment from Figure 1 to multiplex WRI from large cross-
sectional
areas of wind into common turbine feed-stream(s). Figure 3 is a side elevation
view
depicting alternate embodiments of the invention designed to permit harvesting
of
wind-power associated with wind currents circulating around building
structures.
Figure 4 is a side elevation view detailing a single WRI self-aligning
embodiment of
the invention.
Referring now to Figure 1, a stationary embodiment of the invention is shown
which
may advantageously be installed in areas where a unidirectional current of
wind is
typical. Conveniently shown partially in section, this invention allows the
segmenting
of wind collector, turbine and discharge components into separate locations if
required. Wind arriving generally from the direction indicated by arrow 1 is
channeled
by the array of first WRI windward openings 2 of WRI 3 comprised of internally
smooth cylinders of larger diameter necking down into smaller diameter ends
forming
a funnel shape consistent with the neck and throat of a deLaval expansion
nozzle.
Constant wind-force applied at 2 causes WRI form-induced wind (air)
compression as
the air travels into and through smaller WRI ends 3a.
WRI 3 are housed in frame 4 comprised of an assembly of wood or other suitably
strong material backed by a flat sheet of plywood or metal with an array of
holes
bored there-through with a regular spacing such that the smaller diameter ends
of
WRI seated in the holes do so on centers which cause the larger diameter WRI
ends
(prevented from moving laterally by the cradle of frame 4) to touch each other
tangentially without deforming the circular nature thereof. A secondary frame
5 and
backing sheet 6 is affixed to the backside of 4 so that a passageway is
created to
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receive the form compressed air 7. Note that the drawing is partially exploded
at 6 for
purposes of clarity.
Note that although a rectangular array of WRI with an accompanying rectangular
WRI
frame is depicted for later purposes of illustration and later extrapolation
to show the
ease of interconnectivity between WRI frame segments for purposes of achieving
a
large array of usable wind cross-section, it must be understood that any WR.I
frame
form may be utilized with equivalent results obtainable, and in no way is the
rectangular WRI-array form a limitation on this or other embodiments of the
invention.
A wind turbine 8 mounted on shaft 9 and encased within a housing 10 has one or
more variable opening expansion nozzle(s) 11 of the deLaval type which provide
the
only egress for the form-compressed air 7 from the collection component of the
system comprising elements 1 through 6. Form-compressed air 7 entering the
nozzle
from the direction indicated by arrow 12 creates a higher-than-ambient wind
velocity
jet of air arriving tangential to the rotor of disc (wind) turbine 8. Having
only one exit
from the housing 10 through axial exhaust holes 13, the high velocity nozzle
discharge air is restricted to travel in free spiral paths between the discs
of the turbine
8 toward the central exhaust holes 13, and in doing so drag the turbine along
at high
speed owing to the viscosity of the moving air-stream acting on the air
molecules
adhered to the surface of the disc (ie: the boundary adhesion layer). Thereby
turbine
rotation in the direction of the incoming nozzle expansion jet, and at a speed
proportional to the pressure differential across the turbine is developed. Air
exiting
from the axial exhaust holes 13 follows the path indicated by arrows at 14
through the
divergent channel 15 serving to decrease the pressure in the turbine discharge
stream.
Meanwhile, wind is also able to enter as shown by arrow 16 into an external
shroud
17 following path 18 to point 19 where the shroud channel diverges to create a
high-
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velocity low-pressure stream. Optimized design and construction of the shroud
divergent section 19 to coincide with the turbine exhaust divergent section 20
causes
a siphoning effect to be applied to the turbine discharge to the beneficial
increase of
the pressure differential realized across the turbine, and the resultant speed
at which
it turns. A final discharge stream indicated at 21 representing the combined
air-flow
from the WRI cross-sectional area as well as the shroud-flow resumes at normal
wind
speed, thereby resulting in no appreciable fluid drag on the air mass momentum
(ie:
wind-stagnation) in the region of the turbine discharge which tends to
decrement from
the work output achievable by prior art machines.
Not shown in the figure to maintain clarity is the integrated permanent-magnet
(P.M.)
alternator comprising: permanent magnets of Neodymium-Iron-Boron or other high
flux density material of construction mounted in thick end-disc(s) of the disc
turbine;
electromagnet coils with laminated iron cores mounted in the region
surrounding the
disc-turbine runner (rotating member) are mounted on the inside of the disc-
turbine
casing positioned therein to optimally receive maximum magnetic flux from the
rotating permanent magnets, a non-magnetic face-plate to provide a smooth
contiguous wall about the cores (in front of the coils) to allow both a
minimum air gap
between magnets and cores, and to provide minimal air resistance to the
rotation of
the disc-turbine (windage); as well as the P.M. alternator's associated
electrical
conversion and storage means. Also not shown for clarity is the thin gauge
wire mesh
such as 'chicken-wire' mounted across the WRI large diameter open ends which
prevents birds, leaves and other fouling from entering the WRI and also serves
to
secure all WRI to the frame.
The stationary embodiment shown in Figure 1 lends itself readily to conversion
to a
self-guiding embodiment suitable for collecting and converting the energy from
large
cross-sections of wind. Means to make the conversion are detailed in Figure 4,
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wherein a mast 21, lower stationary motion component 22, upper rotatable
motion
component 23 and guide vanes 24 would be added to the system, as shown to the
external shroud. Also, the stationary embodiment shown in Figure 1 lends
itself
readily to an overall 'Wind-Wall' system approach, wherein arraying of further
WRI
frames or extending the length and or height of a singular WRI frame inclusive
of
elements 2 through 6 on the figure allows the harvest of a new wealth of
previously
unrecognized potential for enormous domestic wind-power production.
The Wind-Wall approach provides cost-effective incremental wind-power
integration
into domestic, commercial and industrial green-energy power portfolios by
allowing all
fences and building structures themselves to become WRI structures. In this
manner,
the Wind-Wall incrementally provides larger usable cross-sectional areas of
wind than
prior art methods.
Key to the Wind-Wall approach is the maintenance of preferably one continuous
passageway mapping to one common wind-turbine capable of passing the combined
form-compressed flow there-from. The backing sheet to the passageway, or
channel,
should be advantageously inclined on a path from the periphery of the WRI
frame(s)
along the line of sight toward the turbine inlet nozzle(s) such that the
backing sheet in
the region of the turbine is further (perpendicularly taken) from the WRI
frame than the
backing sheet to WRI frame distance at the WRI frame's perimeter.
It is both desirous and appreciable that a very large number of plastic pop
bottles
(having an optimal large versus small ratio of diameters as well as forms
conducive to
maintaining shock-free streamlined compressible flow there-through) severed
parallel
to the plane of their diameter be tailored to serve as WRI, thereby providing
a raw
material of construction for this embodiment at minimal or no cost. Already in
a highly
refined state for this specific purpose, re-use of plastic bottles for this
application
would increase the life cycle of the plastic in this form by a factor of 10 to
200 times,
thereby diminishing the mass of plastic (bottles) going into refuse, becoming
a benefit
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to humankind in support of 'green' energy production, and decreasing the total
pollution associated with the recycling of plastics.
Referring now to Figures 2a, 2b, and 2c, wind approaching from the direction
indicated by the arrow 1 is consumed by the Wind-Wall at the WRI frame, and
post
traverse of the turbine, discharges either into the leeward side of the frame
alone, or
most advantageously via the method described in conjunction with Figure 1
wherein a
separate high-velocity low-pressure flow stream may be applied to the turbine
discharge for maximum pressure differential across the disc turbine and
realized
electrical work output from the system.
Referring now to Figure 2a, multiplexing of multiple WRI frames together
provides a
Wind-Wall in the form of a windbreak or fence. Figure 2b shows a domestic
building
structure with its typically windward side populated by an array of WRI wind-
harvesting segments. Figure 2c extrapolates further upon the Wind-Wall design,
showing an apartment or sky-rise building used in conjunction with the Wind-
Wall
approach. In this embodiment, WRI frames cover virtually the entire surface
area of
the building (except windows, balconies and doors, etc.). Four separate
channels
(2,3,4,5) within the WRI frameworks collecting form-compressed air from the
four
separate sides of the building increase in width (perpendicular to the face of
the
building) with increased building height such that the channels' horizontally
taken
cross-sectional area at any elevation is not less than the total cross-
sectional area of
all WRI compressed air inlets (small WRI-ends) up to that elevation. This
ensures
that the volume of incoming form-compressed air at any elevation has an
unrestricted
path to the inlet of the turbine (at the top of the building, in this
example). Spill-over of
the separate channel flows (located behind the four Wind-Walls) into
continuations of
the separate channels now flowing underneath shrouds (2',3',4',5') on top of
the
building culminate in deLaval type expansion nozzle(s) respective to each side
of the
building positioned so that its discharge of high velocity air is admitted to
a large disc
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turbine optimally sized to allow high throughput of the expanding form-
compressed
air-mass.
In this example, a rotatably mounted windsock, weather vane, or other type
wind
direction indicator mounted above the turbine carries a permanent magnet gate-
actuator with which to open the spring-loaded normally closed gate permitting
admission of the appropriate shroud flow (the currently pressurized one
according to
the wind indicator) into the turbine. Also the wind direction indicator
actuating the
nozzle gate(s) may itself be built into a shroud covering the turbine
discharge
comprising a divergent conical exhaust channel accompanied (in like fashion to
Figure 1) by a large auxiliary WRI having a converging-diverging section
through
which a high velocity discharge stream inducts the disc-turbine discharge,
bettering
the differential pressure across the system.
It is appreciable that if WRI mounting sheets are chosen to be transparent,
while the
backing sheets are chosen to being advantageously constructed of a dark or
preferably black material, that on sunny days, the whole side(s) of the
building in the
sunshine would become as a solar chimney, creating updraft toward the turbine
located on the roof. Other circumstances may also arise such as being sunny on
one
or two adjacent sides of the building while it is extremely windy on one of
the other
faces of the building. By keeping the building faces isolated from each other,
the
benefit of work output from the system may then be had by more than one source
simultaneously. In multi-source mode, however, the separate deLaval nozzles
respective to the different sides of the building would be inlet points to
separate
segments of an independent set of (side-of-building-specific) discs within the
disc
turbine, all co-mounted on the same shaft, with either common or separate
exhaust
induction streams.
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Referring now to Figure 3, 'Wind-Column' embodiments of the invention are
shown to
be receiving substantially the whole of the wind-mass deflected by the
building
structure shown pre-disposed in the path of the approaching wind. It must be
understood that the home application presented in the figure represents only
one
residential application of this embodiment of the invention, and in no way is
this
intended to be a limitation upon the application of this embodiment, which is
also
applicable for installation onto any existing or proposed structure capable of
supporting the force imposed on the structure due to the deflection of wind
currents
approaching it from any direction, including, but not limited to houses and
buildings,
and any structure of any shape and size.
Considering the wind approaching from the direction indicated by arrows
1(traveling
toward the left hand side of the figure) the air-stream enters the convergent
section of
a shroud 2a collecting wind traveling paths both along the structure surface,
as well
as elevated there-from. Traversing the path indicated by arrows 3, the wind
enters a
divergent section 4 of shroud 2a, where it accelerates to a greater velocity
than the
ambient wind speed. Upon entering into spaces 5 of disc turbine 6, the high
velocity
air-stream causes the rotating member (commonly referred to as the runner) of
the
disc turbine to be dragged along (in direction of arrows on top of the runner)
with the
air-mass passing there-through, owing to the boundary layer adhesion of air to
the
surfaces of the runner, and the viscosity of the air passing by at high speed.
Commonly affixed to shaft 7, all discs of the runner having wind applied
tangentially
thereto contribute to the overall momentum of the runner. Traversing the
spaces 5 of
disc turbine 6 the air-stream moves in streamlined spirals toward the central
exhaust
holes 8 of turbine 6, exiting as indicated by arrows 9 into a divergent
channel 10
serving to add to the differential pressure across the 'Wind-Column' system.
As
shown, a current of wind 11 also freely enters a self-guiding exhaust shroud
12 and
traveling the direction of arrows 13, arrives at a divergent termination zone
14, where
the shroud-flow accelerates upon exiting there-from. Optimal design of the
divergent
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shroud-flow to meet the diverging turbine exhaust stream 15 results in the
beneficiation of the differential pressure across the 'Wind-Column' embodiment
of the
invention via the induction of the disc-turbine diverging exhaust-stream 15
into the
high-velocity low-pressure expanding shroud-flow 16, resulting in a combined
discharge flow 17 from the 'Wind-Column'. Similar to Figure 1 dynamics, the
higher
speed of rotation realized through the induction of the diverging turbine
exhaust
stream into a divergent shroud-flow enables a co-rotating alternator to reach
speeds
in excess of machines in the prior art, thereby generating greater electrical
work
output captured by the system's rectification and storage system connected
thereto.
As shown in the alternate paths of 1 and 1a of air-flow 9 exiting the vertical
'Wind-
Column' on the right hand side of the figure does so through an equally self-
guiding
(for optimal low-pressure application to the discharge side of the disc-
turbine
divergent exhaust channel) exhaust shroud 20. The alternate design which
shelters
the turbine exhaust from back-pressure applied to an otherwise uncovered
divergent
exhaust channel, provides less of a potential personal hazard to anyone
standing
beside the 'Wind-Column', while providing induction (entrainment) of the
divergent
turbine exhaust 9 into the local wind mass 21 resulting in a combined air-flow
22,.
Moving now to a discussion of the horizontal 'Wind-Column' shown on the top of
the
building structure in Figure 3, wind 23 moving to the right in the figure and
deflected
by the rooftop of the building structure is thereby directed into a first
convergent
section of a shroud 26. The compressible wind-mass follows the path indicated
by
arrows 27, and upon reaching the divergent section 28 of the shroud 26,
expands,
and in doing so reaches higher than ambient wind velocity, and in similar
fashion and
with similar rotational velocity and resultant power achievement effects as
that of the
vertical 'Wind-Column' embodiment of the invention, the wind entering into
turbine
casing 29 is applied tangential to the runner therein and passes into the
spaces
between the discs of the turbine 30 generating rotation of the shaft 31 in the
direction
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indicated on the front disc of disc-turbine 30. Air exhausting from the disc
turbine 30
through axial holes 32 then passes into divergent exhaust channel and
induction
shroud (not shown for clarity), and is further entrained by the local wind-
mass passing
by. Note that whether wind is from the left as already described, or
alternately from
the right, entering into shroud 24 and traveling the path indicated by arrows
25 and
expanding in divergent shroud section indicated at 28a, that the resultant
rotation is
the same, so that in changing winds, the turbine momentum will not be
decremented
from.
Not shown for purposes of clarity of detail of the main elements described on
the
figure, are rooftop wind-guides commencing in the corners of the roof,
initially low and
parallel to the long axis of the horizontal wind-turbine shaft, which change
direction on
a smooth curve and rising to full shroud height and meet the shroud parallel
to the
discs of the wind-turbine. Two of these meeting the shroud approximately 20%
of the
way in from the ends of the wind-turbine allow for rooftop collection of winds
substantially approaching the horizontal 'Wind-Column' parallel to its long-
axis, which
would otherwise not be harvestable by the rooftop unit. Alternately, other
rooftop
units arranged at 900 to the longitudinally oriented unit previously described
could be
arranged. Also not shown is the simple (externally responding to wind
direction) self-
actuating mechanical nozzle closure mechanism such as those referred to in
conjunction with previous embodiments of the invention. Note that the nozzle
actuation means would be coincidently integrated with the shroud self-guidance
means thereby requiring zero input work for the actuations, with maximum
resultant
work gain.
The horizontal 'Wind-Column' also provides an ideal means for a domestic solar
chimney / wind-turbine application for buildings covered in a dark (preferably
black)
material or paint. Corrugated transparent polyethylene sheet or similar
material
applied overtop of that would allow air heated by the sun on sunny days within
an air-
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tight external frame cradling the aforementioned elements to freely travel
upward
through the corrugation channels to the top of the building to a separate, or
integrated
Solar and horizontal 'Wind-Column' wind-turbine of optimized disc spacing. The
solar-pressurized feed stream would then provide constant work input on sunny
days,
resulting in a higher net work output. Note that this embodiment provides a
more
effective application for the solar chimney than the 'Wind-Wall', which would
otherwise
'leak' solar-heated air through its WRI holes decrementing from its solar-
chimney-
derived work output.
Referring now to Figure 4, a self-guiding embodiment of the invention 1 is
disposed in
the path of wind moving to the right as indicated by arrow 2. Wind passing
into the
region of the invention may follow path 3 entering into a substantially
convergent
section of a singular large WRI 4 forming the intake of the embodiment (of
general
form already discussed in conjunction with the description of Figure 1), or
alternately,
the wind may follow path 5 entering into the external shroud 6.
Describing the internal flow path as a first course of description, the
compressible air-
mass driven forward by the momentum of the natural wind current follows the
path
indicated by arrows 7 into and through a convergent section 8 where the air-
mass
becomes compressed. Subsequently entering into a substantially divergent
section 9
consistent with the design of a deLaval type expansion nozzle optimized for
the
generally low pressure application, the air-mass upon expansion achieves a
velocity
in excess of the ambient wind velocity, and approaches the runner of disc-
turbine10
tangentially. Entering into the spaces between the discs of the runner, the
disc-
turbine is dragged along in the direction of the incoming high velocity
expanding air
stream as indicated by the arrow on the front disc of the disc-turbine 10,
thereby
driving the shaft 11 of disc-turbine 10 at speeds in excess of wind-driven
machines in
the prior art. Having given up a high percentage of its available kinetic
energy in
imparting momentum to the discs of the disc-turbine 10, air exits to either
side of the
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disc-turbine 10 through axial exhaust openings 12 provided for the purpose.
Following the path indicated by arrows 13 through substantially divergent
exhaust
channel 14, the air exits the internal divergent channel terminating at 15.
Meanwhile, wind entering into the first slightly convergent section of
external shroud 6
and following the path indicated by arrows 16 upon reaching the divergent
section 17
of the shroud 6 expands, and upon doing so generates a high velocity discharge
stream 18 which entrains a goodly percentage of the internal turbine exhaust
stream
at 19, placing the discharge air 13 from the divergent section of the disc-
turbine
exhaust channel 15 substantially under suction, thereby beneficiating the
differential
pressure across the disc-turbine system embodiment 1, the speed of its shaft
11
rotation, and the resultant electrical work output realized from its co-
rotating
alternator. As shown, post entrainment of the turbine exhaust stream into the
high-
velocity low-pressure shroud flow, the total air-stream 20 resumes traveling
with the
local wind-mass at a speed substantially the same as the native wind, thereby
achieving operation substantially without stagnation of the air-stream at and
up-wind
of the WRI 4.
As shown a strong mast 21 supporting the stationary component of a motion 22
capably supports the weight of the embodiment 1. An upper rotatably mounted
component 23 of the motion 22 (inclusive of internally mounted and freely
turning
bearing means) is rigidly affixed to the lower half 22 and is fully capable of
supporting
the total structure weight and transverse loads applied to same in strong wind
conditions of operation. The self-aligning embodiment of the invention 1 is
provided
with at least one longitudinally projecting guide vane 24 mounted thereupon of
sufficient area, that for any change of wind direction, the invention tracks
the wind
thereby maintaining its WRI in diametric opposition to the approaching winds.
This
preferred self-guided embodiment of the invention achieves a maximum of
upstream-
of-turbine freely obtained air compression, as well as an optimized pressure
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differential across the turbine provided through the maximization of the
induction
provided by the separate shroud-flow downstream of the disc-turbine divergent
discharge.
Referred to, however, not shown in any of the embodiment Figures is the
variable
orifice expansion nozzle(s) responding proportionally to wind pressure which
is
provided by a cam actuating one half (or both halves) of a contoured nozzle
segment,
having a spring-return (upon closing) mechanism attached thereto on one end,
and to
a connection rod or cable leading to a target mounted on sliding means located
within
the external shroud flow such that upon increasing air-velocity in the shroud
flow, a
proportional amount of opening, and appropriate contour of form is presented
to the
expanding air-stream entering the disc-turbine casing to benefit the expansion
of
available wind-pressure made available by the invention embodiment.
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