Note: Descriptions are shown in the official language in which they were submitted.
CA 02709638 2010-06-16
P.7752/Ir/Pa
A-HEAT ALLIED HEAT EXCHANGE TECHNOLOGY AG,
D-80339 Munchen, Germany
Heat exchange system
The invention relates to a modular heat exchange system having a heat
exchange module in accordance with the preamble of independent claim 1.
The use of heat exchange systems is known in a number of applications from
the prior art which can practically not be overseen. Heat exchangers are used
in refrigeration systems such as in common domestic refrigerators, in air-
conditioning systems for buildings or in vehicles of all kinds, in particular
in
motor vehicles, aircraft and ships, as water coolers or as oil coolers in
combustion engines, as condensers or evaporators in refrigerant circuits and
in further innumerable different applications which are all well-known to the
person of ordinary skill in the art.
In this respect, there are different possibilities of sensibly classifying the
heat
exchangers from very different applications. One attempt is to carry out a
distinguishing by the structure or by the manufacture of the different types
of
heat exchangers.
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A division can thus be made in accordance with so-called "finned heat
exchangers", on the one hand, and "minichannel" or "microchannel" heat
exchangers, on the other hand.
The finned heat exchangers which have been well-known for a very long time
serve, like all types of heat exchangers, for the transfer of heat between two
media, e.g., but not only, for the transfer from a cooling medium to air or
vice
versa, such as is known, for example, from a classical domestic refrigerator
in
which heat is emitted to ambient air via the heat exchanger for the production
of a cooling capacity in the interior of the refrigerator.
1o The ambient medium outside the heat exchanger, that is e.g. water, oil or
frequently simply the ambient air, which takes up the heat, for example, or
from which heat is transferred to the heat exchanger, is either cooled or
heated accordingly in this process. The second medium can e.g. be a liquid
cold carrier or heat carrier or an evaporating or condensing refrigerant. In
any
case, the ambient medium, that is e.g. the air, has a substantially lower heat
transfer coefficient than the second medium, that is e.g. the refrigerant,
which
circulates in the heat exchanger system. This is balanced by highly different
heat transfer surfaces for the two media. The medium with the high heat
transfer coefficient flows in the pipe which has a very enlarged surface at
the
outer side at which the heat transfer e.g. to the air takes place by thin
metal
sheets (ribs, fins).
Fig. 3 shows a simple example of an element of such a finned heat exchanger
which is known per se. In practice, the heat exchanger is formed in this
respect by a plurality of such elements in accordance with Fig. 3.
The ratio of the outer surface to the inner surface depends in this respect on
the fin geometry (= pipe diameter, pipe arrangement and pipe spacing) as well
as on the fin spacing. The fin spacing is selected differently for different
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applications. However, it should be as small as possible from a purely
thermodynamic aspect, but not so small that the pressure loss on the air side
is too large. An efficient optimum is at approximately 2 mm, which is a
typical
value for the condenser and the heat exchanger.
The manufacture of these so-called finned heat exchangers takes place in
accordance with a standardized process known for a long time. The fins are
stamped using a press and a special tool and are placed in packets with one
another. Subsequently, the pipes are pushed in and expanded either
mechanically or hydraulically so that a very good contact, and thus a good
heat transfer, arises between the pipe and the fin. The individual pipes are
then connected to one another, often soldered to one another, by bends and
inlet tanks and outlet tanks.
The efficiency is in this respect substantively determined by the fact that
the
heat which is transferred between the fin surface and the air has to be
transferred to the pipe via heat conduction through the fins. This heat
transfer
is the more effective, the higher the conductivityor_ the thickness of the fin
is,
but also the smaller the spacing between the pipes is. One speaks of fin
efficiency here. Aluminum is therefore primarily used as the fin material
today
which has a high heat conductivity (approx. 220 W/mK) at economic
conditions. The pipe spacing should be as small as possible; however, this
results in the problem that many pipes are needed. Many pipes mean high
costs since the pipes (made from copper as rule) are much more expensive
than the thin aluminum fins. These material costs could be reduced in that the
pipe diameter and the wall thickness are reduced, i.e. a heat exchanger is
made with a number of small pipes instead of with a few larger pipes. This
solution would be ideal thermodynamically: Very many pipes at small
distances with small diameters. A substantial cost factor is, however, also
the
labor time for the widening and soldering of the pipes. It would increase
extremely with such a geometry.
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A new class of heat exchangers, so-called minichannel or also microchannel
heat exchangers, was therefore already developed some years ago which are
manufactured using a completely different process and almost correspond to
the ideal of a finned heat exchanger: many small pipes at small intervals.
Instead of small pipes, however, extruded aluminum sections are used in the
minichannel heat exchanger which have very small channels with a diameter
of e.g. approximately 1 mm. Such an extruded section likewise known per se
is shown schematically e.g. in Fig. 2. In practice in this respect, a heat
exchanger can already manage, depending on the required heat capacity,
with one single extruded section as a central heat exchange element. To be
able to achieve higher heat transfer capacities, a plurality of extruded
sections
can naturally also be provided simultaneously in one single heat exchanger
which are connected to one another, e.g. soldered to one another, in suitable
combinations, for example via inlet feeds and outlet feeds.
Such sections can e.g. be manufactured in suitable extrusion processes
simply and in a variety of shapes from a plurality of materials. However,
other
manufacturing processes are also known for the manufacture of minichannel
heat exchangers such as the assembly of suitably shaped sectional metal
sheets or other suitable processes.
These sections cannot, and also do not have to, be widened and they are also
not pushed into stamped fin packets.
Instead, for example, sheet metal strips, in particular aluminum strips, are
placed between two sections disposed close to one another (common
spacings, for example, < 1 cm) so that a heat exchanger packet arises by
alternating placing of sheet metal strips and sections next to one another.
This
packet is then soldered completely in a soldering furnace.
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A heat exchanger having a very high fin efficiency and a very small filling
volume (inner channel side) arises due to the narrow spacings and the small
channel diameters. The further advantages of this technique are the
avoidance of material pairings (corrosion), the low weight (no copper), the
high pressure stability (approx. 100 bar) as well as the compact construction
shape (typical depth of a heat exchanger e.g. 20 mm).
Minichannel heat exchangers became established in mobile use in the course
of the 1990s. The low weight, the small block depth as well as the restricted
dimensions required here are the ideal conditions for this. Automotive
radiators as well as condensers and evaporators for automotive air-
conditioning systems are today realized almost exclusively with minichannel
heat exchangers.
In the stationary area, larger heat exchangers are usually needed, on the one
hand; on the other hand, the emphasis here is less on the weight and the
compact design and more on the ideal price-performance ratio. Minichannel
heat exchangers were previously too limited in dimensions to be considered
for this purpose. Many small modules would have had to be connected to one
another in a complex and/or expensive manner. In addition, the use of
aluminum is relatively high in the extruded sections so that a cost advantage
was also practically not to be expected from the material use aspect.
Due to the high volumes in the automotive sector, the manufacturing
processes for minichannel heat exchangers have become standardized and
have improved so that this technology can today be called mature. The
soldering furnace size has also increased in the meantime so that heat
exchangers can already be produced in the size of approximately 1 x 2 m.
The initial difficulties with the connection system have been remedied. In the
meantime, there are a plurality of patented processes on how the inlet tanks
and outlet tanks can be soldered in.
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However, above all the price of copper, which has increased greatly with
respect to aluminum, has had the result that this technology is also becoming
very interesting for stationary use.
In addition to the simple systems in which substantially only one ambient
medium, such as air, is available to the heat exchanger for the exchange of
heat, so-called hybrid coolers or hybrid dry coolers are known such as are
e.g.
disclosed in W090/15299 or in EP 428 647 131, in which the gaseous or liquid
medium of the primary cooling circuit to be cooled flows through a fin heat
exchanger and which output the heat to be dissipated via the cooling fins to
the air flow partly as sensitive heat and partly as latent heat. One or more
fans
convey the air flow through the heat exchanger and advantageously have
variable speeds. The dissipation of the latent heat takes place by a liquid
medium, preferably water, which is matched by its specific values such as
conductivity, hardness, carbonate content and is in each case added to the
heat transfer surface on the air side as a drop-forming liquid film. The
excess
water drips into a collection bowl directly beneath the heat exchanger
elements. Sprayed heat exchanger concepts are also known where water is
sprayed onto the fin heat exchanger and evaporates completely and in this
process the evaporation energy is used for the improvement of the heat
transfer as in the wetting for energetic optimization. It is also possible to
work
without a water excess here, but a formation of deposits has to be prevented,
for which purposes e.g. VE water is used.
It is understood that other cooling fluids such as oil can also be considered
in
addition to water in special cases.
The manner of operation in the wetting or spraying of the fins of the heat
exchanger results in substantial energy and water savings in comparison with
customary methods such as with open cooling towers. However, the
restriction in the choice of material of the wetted or sprayed heat exchanger
in
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conjunction with the fin where corrosion may not occur in connection with an
electrolyte is disadvantageous.
Hybrid heat transfer is thus understood as the substantial improvement of the
heat transfer of fin heat exchangers with pipes by direct wetting or spraying
of water. It is above all necessary in this respect to regulate the air speed
in
the fin packet so that no taking along of water occurs at the fin surface.
This
is advantageously achieved by a speed regulation of the fans or by other
suitable measures.
It is a disadvantage in this respect that the sprayed or wetting water acts as
an electrolyte together with dissolved ions, which can result in numerous
corrosion problems with the usually used material pairings of copper pipe
and aluminum fins of the heat exchanger.
It is known in this respect e.g. to use so-called cataphoretic dip coating as
a
suitable surface protection for heat exchangers. Furthermore, both the
material pairings such as copper pipe and copper fin and aluminum pipe and
aluminum fin as well as stainless steel pipe and stainless steel fin are used
to master the problems of contact corrosion. It is also known to zinc coat the
heat exchangers completely. High demands are made on the quality of the
circulation water or spray water in this respect with regard to the pH values,
water hardness, chlorine content, conductivity, etc. to prevent deposits from
forming, on the one hand, on condensation on the fin due to evaporation and
from contents of chemically reactive materials forming which are too high, on
the other hand, which can on their part result in corrosion together with the
deposits.
To achieve higher heat transfer capacities than are e.g. known with small heat
exchangers from automotive engineering or domestic technology, attempts
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have previously been made to make use of the previously described hybrid
technology with larger heat transfer systems.
Another possibility to reach larger heat transfer capacities basically
involves
trying to achieve greater exchange rates by interconnection of a plurality of
individual heat exchange components, e.g. by the connection of Al-MCHX
modules.
A problem with all previously known heat exchange systems in this respect is
the contamination of the system components of the heat exchange system,
which can generally not be avoided in the operating state. The heat
1o exchangers past which the cooling air is conducted using corresponding fans
can be contaminated more and more over time by contaminants of all kinds
which are contained in the cooling air, which can, for example, have the
result
that the heat transfer coefficient of the surface of the heat exchanger is
reduced so that the heat transfer capacity is reduced. This can result in
increased operating costs or, in extreme cases, the heat exchange systems
can no longer provide the required heat exchange performance at all, which in
worst case scenarios can result in serious damage. For example, that a
connected machine to be cooled such as a data processing systems or an
internal combustion engine or another machine overheats and is thereby
damaged. But also products such as to foodstuffs which are stored in a cold
store can go off, for example, with deficient refrigerating.
The heat exchange systems must therefore be cleaned regularly, which is,
however, difficult and thus complex and expensive in the known systems. It is
furthermore necessary in many known heat exchange systems to open a
housing in order e.g. to clean the heat exchanger itself or to clean other
major
components in the interior of the heat exchanger. The opening of the housings
is therefore not only complex and awkward. In this case, the corresponding
connected heat engines also have to be taken out of operation since
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otherwise an opening of the housing of the heat exchange system is not
allowed for safety reasons alone or is not possible at all for technical
reasons
in the operating state.
A further problem is that the cleaning liquid with which the heat exchange
system is cleaned, for example water, water mixed with a cleaning agent or
another cleaning liquid has to be collected in a complex and/or expensive
manner so that it can be disposed of professionally. As a rule, the cleaning
liquid contaminated after the cleaning process may not simply be supplied to
the sewers. Corresponding complex and/or expensive apparatus, for example,
separators, separate channel systems via which contaminated cleaning liquid
is led away and supplied to a collection point or other separation and
collection systems known per se are therefore provided in the known heat
exchange systems which not only take up additional space, but are also
expensive in construction and in operation.
It is therefore the object of the invention to provide an improved heat
exchange system which overcomes the problems known from the prior art,
which is in particular simple to clean, can preferably also be cleaned in the
operating state and with which a contaminated cleaning liquid can be captured
or collected and disposed of simply.
The subjects of the invention satisfying these objects are characterized by
the
features of independent claim 1.
The dependent claims relate to particularly advantageous embodiments of the
invention.
The invention thus relates to a heat exchange system having a heat exchange
module including at least one first heat exchange module with a heat
exchanger, with an external boundary of the heat exchange module being
formed by an inflow surface and an outflow surface such that, for the
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exchange of heat between a transport fluid and a heat transfer agent flowing
through the heat exchanger in the operating state, the transport fluid can be
supplied via the inflow surface to the heat exchange module, can be brought
into flow contact with the heat exchanger and can be led away again from the
heat exchange module via the outflow surface. In accordance with the
invention, in this respect, a cleaning system is provided with a cleaning
flap.
It is thus important for the invention that a cleaning system with a cleaning
flap
is provided in a heat exchange system of the present invention, said cleaning
flap being able to be opened and closed simply so that access is provided to
the interior of the heat exchange module which allows cleaning and service
work, basically even in the operating state of the heat exchange system,
without having to disassemble the heat exchange system.
In a preferred embodiment, the cleaning system of the present invention
includes a cleaning opening and/or a dust capturing grid and/or a scraper
and/or a washing device whose function is generally known to the skilled
person. The heat exchanger can in particular be provided at the cleaning flap
and/or the heat exchanger is itself made as a cleaning flap, which in special
cases and depending on the application can substantially facilitate service
and
cleaning work.
The cleaning flap is particularly preferably rotatably supported around an
axis
of rotation for the opening of the heat exchange module so that the cleaning
flap is a collection pan for a cleaning agent in an opened state. It is
thereby
possible that a contaminated cleaning agent can automatically be collected in
the collection pan and can be supplied to a professional disposal without
further construction measures.
In another embodiment, a first boundary surface of the first heat exchange
module is inclined at a presettable angle of inclination with respect to a
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second boundary surface of the first heat exchange module. In this respect,
the heat exchanger itself can have a supporting function on the formation of
the heat exchange module; for example, in that it forms a statically integral
construction element of a housing of the heat exchange module. This can, for
example, be realized in that the heat exchanger itself forms a housing wall of
the heat exchanger module or in that the housing of the heat exchanger
module does not have a boundary wall at all the boundary surfaces of the
housing so that the heat exchanger itself satisfies a connecting and
stabilizing
integral static function as a housing component.
In a further simple embodiment, a boundary surface of the heat exchange
system can be dispensed with at its housing with the omitted housing wall
being formed in the installed state of the heat exchange system by a wall of
an
installation object, in particular by a wall of a housing.
To increase the heat exchange performance, the heat exchange system can
in particular be formed from a plurality of heat exchange modules.
Above all, but not only, in those cases in which the heat exchange system is
formed from a plurality of heat exchange modules, the first boundary surface
of the first heat exchange module can be inclined at the presettable angle of
inclination with respect to the second boundary surface of the first heat
exchange module such that the modular heat exchange system can be
expanded by a second heat exchange module, in particular in compact
construction, with the second heat exchange module preferably being identical
to the first heat exchange module. For example, a heat exchange system can
thus be provided by two heat exchange modules which are triangular in cross-
section and whose first and second boundary surfaces are inclined at 45 to
one another, said heat exchange system having a rectangular or square
cross-section surface in that the two inclined surfaces are arranged against
one another.
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The angle of inclination between the first boundary surface and the second
boundary surface of the heat exchange module is in this respect between 0
and 180 , specifically between 20 and 70 , preferably between 40 and 50 ,
and particularly preferably amounts to 45 .
If, for example, the heat exchange modules are therefore made in the form of
a parallelepiped having an angle of inclination of 45 , two respective such
heat
exchange modules can be assembled in a particularly compact manner, e.g.
via the inclined surfaces, and can also, if required, be expanded as desired
by
being strung next to one another.
The heat transfer capacity and/or the power density of the heat transfer can
thus be matched in a simple and efficient manner by a modular heat transfer
system of the present invention by the regular repetition of preferably
identical
heat exchange modules or by the removal of identical heat exchange
modules.
In a particularly preferred embodiment, the first boundary surface of the
first
heat exchange module is thus inclined at the presettable angle of inclination
with respect to the second boundary surface of the first exchange module
such that the modular heat exchange system can be expanded by a second
heat exchange module, in particular in a compact construction shape, with the
second heat exchange module preferably being identical to the first heat
exchange module. In this respect, compact construction shape means that
two heat exchange modules can be combined with one another in as space
saving a manner as possible so that as little free space as possible,
preferably
practically no free space at all, remains between two combined heat exchange
modules.
A particularly important significance thus accrues to those embodiments in
accordance with the invention in which the heat exchange system is formed
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from a plurality of heat exchange modules since the heat transfer capacity can
be reduced particularly simply in them, for example, by removal of a heat
exchange module.
For the further increase of the power density of the heat transfer between the
heat transfer agent and the transport fluid and/or for the increase of a heat
transfer capacity between the heat transfer agent and the transport fluid, a
cooling device can be provided for the cooling of the heat exchanger, in
particular a fan for the generation of a gas flow, and/or the heat exchange
system can, as known per se and as initially described in detail, be made as a
hybrid system, and a sprinkling device can be formed for the sprinkling of the
heat exchanger with a cooling fluid, in particular with cooling water. In this
respect, a drop separator can also particularly advantageously be provided for
the separation of the cooling fluid.
In this respect, the heat exchanger itself, as known per se from the prior
art,
can be made by a plurality of microchannels as a microchannel heat
exchanger and/or the heat exchanger can also be made as a finned heat
exchanger with cooling fins. Specifically, the heat exchange system is made
as a combination heat exchange system of the finned heat exchanger and the
microchannel heat exchanger if specific demands prefer such a construction
shape.
To improve the possibilities of regulating the heat transfer capacity of a
heat
exchange system in accordance with the invention, a sealing, in particular an
air sealing, can be provided for the regulation of a flow rate of the
transport
fluid which can be controlled and/or regulated either manually or via a
control
unit in dependence on a presettable operating parameter.
Furthermore, a compensation means known per se can very advantageously
also be provided for the compensation of thermomechanical strains.
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The components of the modular heat exchange system of the present
invention, that is, for example, the heat exchangers and/or a supply line
and/or
an outlet line for the heat transfer agent and/or the cleaning flap and/or any
other component of a heat exchanger system, can be connected by a
universal connection element to every other component of the heat exchange
system so that, for example, a heat exchange module can be added or
removed particularly easily. Specifically, the cleaning flap and the inlet
tanks
and outlet tanks for the heat transfer agent or also sheet metal parts and
other
modules and components of the heat exchange system are particularly
preferably connected to a universal connection element. In this respect, these
universal connection elements are particularly well suited both for the
vertical
installation and for the horizontal installation of the heat exchange systems
or
of the heat exchange modules.
As a rule, but not necessarily, a control unit, in particular a control unit
having
a data processing system for the control of the cooling device and/or of the
cleaning system and/or of the air sealing and/or of an operating or state
parameter of the heat transfer agent and/or of another operating parameter of
the heat exchange system is provided for the control and/or regulation of the
heat exchange system, such as is known to the skilled person per se from the
prior art with existing heat exchange systems.
The heat exchange system or the heat exchange module and/or the heat
exchanger and/or a boundary surface of the heat exchange module,
specifically the total heat exchange system, is particularly advantageously
produced from a metal and/or a metal alloy, in particular from a single alloy,
and can in particular be produced from stainless steel, specifically from
aluminum or from an aluminum alloy, with a sacrificial metal preferably being
provided as corrosion protection and/or with the heat exchange system being
at least partly provided with a protective layer, in particular with a
corrosion
protective layer. Particularly the inlet tanks and outlet tanks are preferably
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produced for high pressures, for example for operation with C02, from very
strong materials such as stainless steel.
A heat exchange system in accordance with the invention is specifically a
radiator, in particular a radiator for a vehicle, specifically for a land
vehicle, for
an aircraft or for a water vehicle, or a cooler, a capacitor or an evaporator
for a
mobile or stationary heating plant, refrigerating plant or air-conditioning
plant,
in particular a cooler apparatus for a machine, a data processing system or
for
a building or for another apparatus which can be operated with a heat
exchange system.
The invention will be explained in more detail in the following with reference
to
the drawing. There are shown in a schematic representation:
Fig. 1 a a first embodiment of a heat exchange system in accordance
with the invention in the operating state;
Fig. 1 b the heat exchange system of Fig. 1 a during a cleaning process;
Fig. 2 a heat exchanger having microchannels;
Fig. 3 an element of a finned heat exchanger;
Fig. 4 a second embodiment of a heat exchange system in accordance
with the invention with a lateral cleaning flap;
Fig. 5 a further embodiment in accordance with Fig. 4 with air sealing;
Fig. 6a another embodiment in accordance with Fig. 1 a with a universal
connection element;
Fig 6b a universal connection element of Fig. 6a in detail;
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Fig. 7 a heat exchange system in accordance with the invention with
two heat exchange modules.
Fig. 1 a and Fig. 1 b show in a schematic representation a first simple
embodiment of a heat exchange system in accordance with the invention
which is provided as a whole with the reference numeral 1 in the following. In
this respect, the heat exchange system is shown in the operating state in Fig.
1 a, whereas Fig. 1 b shows the same heat exchange system during a cleaning
process.
The heat exchange system 1 in accordance with the invention of Fig. 1 a or
Fig. 1 b includes as a major element a heat exchange module 2, 21 having a
heat exchanger 3 for the exchange of heat between a heat agent 6, e.g. a
cooling liquid 6 or an evaporating agent 6, and a transport fluid 5, e.g. air
5.
The heat exchanger 3 in the present case is a microchannel heat exchanger 3
known per se with a plurality of microchannels 31. The microchannels 31 of
the heat exchanger 3 are connected via a connection system, which is not
shown in Fig. 1 a and Fig. 1 b and which is generally known to the skilled
person, to a refrigeration machine, likewise not shown, for the exchange of
heat transfer agent 6.
The refrigeration machine is flow connected in a manner known per se to the
connection system, including an inlet channel with an inlet segment of the
heat exchanger 3 and an outlet channel with an outlet segment of the heat
exchanger 3, such that the heat transfer agent 6 for the exchange of heat with
the air 5 can be supplied from the inlet channel via the inlet segment,
through
the plurality of microchannels 31 of the heat exchanger 3 and finally via the
outlet segment to the outlet channel .
An outer boundary of the heat exchange module 2, 21 is in this respect
formed by an inflow surface 41 and an outflow surface 42 such that in the
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operating state for the exchange of heat between the transport fluid 5, whose
flow direction is shown symbolically by the arrows 5, and the heat transfer
agent 6 flowing through the heat exchanger 3, the transport fluid 5 can be
supplied to the heat exchange module 2, 21 via the inflow surface 41, can be
brought into flow contact with the heat exchanger 3 and can be led away
again from the heat exchange module 2, 21 via the outflow surface 42.
So that the heat can be exchanged better between the air 5 and the heat
transfer agent 6, a cooling device 10 is additionally provided, in the present
case a fan 10, with which a quantity of air 5 can be controlled which is
conveyed through the heat exchange module 2, 21 per time unit.
In this respect, a first boundary surface 9, 91, which is formed in the
present
case by the heat exchanger 3 itself, is inclined with respect to a second
boundary surface 9, 92 of the first heat exchange module 2, 21 at a
presettable angle of inclination a which amounts to approximately 45 in the
present specific example. It is understood that in another embodiment the
angle of inclination a can also have a different value, e.g. a value greater
or
smaller than 45 , e.g., but not only, 25 or 46 . In the simple embodiment in
accordance with Fig. 1, in this respect, the second boundary surface 92 is
formed by a wall 9 of an installation object which in the present case is a
cold
store not shown in any more detail.
In accordance with the present invention, a cleaning system 7 with a cleaning
flap 71 is furthermore provided as a major element, with Fig. 1 a showing the
heat exchange system 1 in the operating state in which the interior, in
particular the surface of the heat exchanger 3, gradually becomes dirty. Fig.
1 b, in contrast, shows the heat exchange system 1 during a cleaning process.
The cleaning flap 71 is designed as an access flap 71 which is made rotatable
around the axis of rotation 711 in accordance with the arrow P so that access
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is provided by a pivoting of the cleaning flap 71 around the axis of rotation
711, which can be made as a universal connection element 12, for example,
said access enabling service and repair and cleaning work simply in the
interior without the heat exchange system I having to be disassembled or,
depending on the specific embodiment, without the heat exchange system
having to be switched off. This means that since the cleaning flap can also be
opened simply in the operating state, a cleaning of the heat exchange system
1 is also possible in the operating state by the present invention.
Fig. 1 b shows a situation in which the heat exchanger 3 is just being cleaned
with a cleaning liquid 714, for example with water 714. The cleaning flap 71
was pivoted, starting from the situation of Fig. 1 a, by 270 around the axis
of
rotation 711 such that it acts, in accordance with Fig. 1 b, as a collection
pan
712 which reliably collects the contaminated cleaning liquid 714 during the
cleaning process so that the contaminated cleaning liquid can be led away
and disposed off safely, and optionally automatically, so that damage to the
environment is avoidable, for example.
A heat exchanger 3, 300 in accordance with Fig. 1 with microchannels 31 is
shown schematically in section in Fig. 2. Instead of small pipes such as are
used in the classical finned heat exchangers 3 in accordance with Fig. 3, as
already mentioned, extruded aluminum sections are e.g. used in minichannel
heat exchangers 300 which have very many small channels 31 with a
diameter of e.g. approximately 1 mm. The heat exchanger 3 of Fig. 2 can e.g.
be manufactured simply in a variety of shapes from a plurality of materials in
a
suitable extrusion process. In this respect, the heat exchanger 3 in
accordance with Fig. 2 can also be manufactured in another embodiment
variant not explicitly shown in Fig. 2, by other manufacturing processes such
as e.g. by the assembly of suitably shaped sheet metal sections or by other
suitable processes.
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In contrast to Fig. 2, Fig. 3 shows an element of a finned heat exchanger 3,
301 known per se with cooling fins 32 such as could likewise be used instead
of a microchannel heat exchanger 300 in an embodiment of the present
invention. The heat transfer agent 6 flows through the tubular element of the
finned heat exchanger 3, 301 which, in the operating state, mainly exchanges
heat via the cooling fins 32 with the air 5 flowing past. It is understood
that in
practice the heat exchanger 3 is as a rule made from a plurality of elements
in
accordance with Fig. 3. In a very special embodiment of the present invention,
which is not shown explicitly with reference to a drawing for space reasons, a
combination heat exchanger 3, 300 301 is used as the heat exchanger 3. This
means that a heat exchange system 1 of the present invention can
simultaneously include, in addition to a heat exchanger 300 with a plurality
of
microchannels 31, a finned heat exchanger 301 with cooling fins 32 for very
special applications.
To cope with any even larger heat transfer capacities, the heat exchange
system 1 can also be made as a so-called hybrid system 1 whose functional
principle is likewise known to the skilled person per se and therefore does
not
have to be shown explicitly with reference to a separate drawing. In this
case,
a sprinkling device is preferably provided for the sprinkling of the heat
exchanger 3, 300, 301 with an external cooling fluid, in particular with
cooling
water or cooling oil. Specifically, a drop separator can additionally be
provided
e.g. in the form of a pan for the separation and collection of the external
cooling fluid in the operating state so that the external cooling fluid can be
recycled in an external cooling system which serves for the cooling of the
external cooling fluid and can be supplied to the heat exchanger 3, 300, 301
again via the sprinkling system for the repeat cooling of the heat exchanger.
A second embodiment of a heat exchange system 1 in accordance with the
invention is shown schematically with a lateral cleaning flap 71 in Fig. 4.
The
embodiment of Fig. 4 differs in this respect from that of Fig. 1 a in that the
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cleaning flap 71 is provided laterally in accordance with the invention at the
heat exchange module 2, 21, i.e. the cleaning flap 71 is representation
orthogonally to the surface of the heat exchanger 3. To keep the total
construction shape of the heat exchange module 2, 21 as compact as
possible, the cleaning flap 71 only covers the cross-section of the heat
exchange module, from which the shown triangular shape of the cleaning flap
71 results. In the cleaning or service case, the cleaning flap 71 can be
pivoted
around the axis of rotation 711 in the direction of the arrow P to open the
heat
exchange system 1, whereby access is provided to the interior of the heat
exchange system 1.
A collection pan 73 is additionally provided in the example of Fig. 4, which
can
naturally also be omitted if not necessary, for the collection and reliable
leading away of the leaning liquid 713 which arises on a cleaning of the heat
exchange system 1.
A further embodiment in accordance with Fig. 4 is shown schematically with
an air sealing 11 in Fig. 5. The air sealing 11 is preferably made in the form
of
a sun blind or of a Venetian blind, including individual sun blind elements
111
or Venetian blind elements 111, so that the degree of covering of the heat
exchanger 3 can be changed variably, preferably in electronically controlled
and/or regulated form, in that the air sealing is removed in a known manner,
wholly or partly for example, from the surface of the heat exchanger 3 by
gathering together the individual sun blind elements 111 or Venetian blind
elements 111 or in that an angle between the individual Venetian blind
elements 111 and the surface of the heat exchanger 3 is changed so that the
effective passage area for the air 5 can be varied. A regulation of the heat
exchange performance of the heat exchanger 3 is thereby possible in a
simple manner without changing the flow dynamics in the cooling system.
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In the embodiment of Fig. 5, a further possible variant is additionally shown
for
a lateral cleaning flap 71 in accordance with Fig. 4. In contrast to the
lateral
cleaning flap 71 of Fig. 4 which has a triangular shape, the cleaning flap 71
of
Fig. 5 is made rectangular or square such that it approximately covers twice
the cross-sectional surface of the heat exchange module 2, 21 and is
supported rotatably by 2700 around the axis of rotation 711 such that it can
simultaneously be used, analog to the embodiment of Fig. 1 b as a collection
pan 712 for the cleaning agent 713 during a cleaning process.
Another embodiment of a heat exchange system 1 in accordance with the
invention is shown schematically in Fig. 6a in which the cleaning flap 71 is
fastened to a universal connection element 12 in accordance with Fig. 6b. The
universal connection element 12 is inter alia suitable for the simple and
reliable connection of inlet tanks and outlet tanks known per se and not shown
explicitly in Figs. 6a and 6b which serve for the supply or leading away of
the
heat transfer agent 6 to or from the heat exchanger 3 respectively.
The universal connection element 12 is preferably designed such that it can
be connected to the corresponding parts of the heat exchange system 1
particularly simply via a screw connection, for example, or by soldering.
It can serve for the connection of lines which conduct heat transfer agent 6
or
can even itself be suitable as a line for the conveying of heat transfer agent
6.
It can furthermore be suitable for the connection of sheet metal parts such as
the cleaning flap 71 or other parts. In a given modular heat exchange system
1, the universal connection element 12 is preferably made in detail such that
it
can provide as many different connections as possible simultaneously in one
and the same embodiment so that as few differently made universal
connection elements as possible have to be used simultaneously in one and
the same modular heat exchange system 1.
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In the ideal case, the universal connection element 12 is made such that it
can
simultaneously take over all connection functions between all parts of the
modular heat exchange system so that only one single type of universal
connection element has to be used in one and the same heat exchange
system 1, which hugely simplifies the structure, the expansion or the
reduction
of a modular heat exchange system 1 in accordance with the invention and
thus guarantees very high flexibility of the system.
Fig. 7 finally shows a modular heat exchange system 1 in accordance with the
present invention which includes two identical heat exchange modules 2, 21,
22. The two modules are of identical construction shape, with the angle of
inclination a having a value of preferably, but not necessarily, 45 . The
skilled
person will immediately understand that basically any desired number of
identical heat exchange modules 2, 21, 22 can be added perpendicular to the
double arrow DP, that is parallel to the plane of the drawing. This means that
only one single type of heat exchange modules 2, 21, 22 has to be provided to
change the heat exchange performance of the modular heat exchange system
1 to provide a system 1 with practically any desired presettable heat exchange
performance or to expand it or to reduce the heat exchange performance in an
existing system by a reduction of the number of the heat exchange modules 2,
21, 22. The individual heat exchange modules 2, 21, 22 are particularly
preferably integrated in the heat exchange system 1 by use of the universal
connection elements 12, as was already discussed with reference to Fig. 6a
and Fig. 6b. Analog to Fig. 1 a or Fig. 1 b, the two cleaning flaps 71 are
preferably each pivotable by 270 around the axes of rotation for service and
cleaning purposes so that the cleaning flaps 71, as already explained a
multiple of times above, can simultaneously serve as a collection pan 712 for
a cleaning agent 713.
It is understood that the embodiments described within the framework of this
application are only to be understood as examples. This means that the
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invention is not solely restricted to the specific embodiments described. All
suitable combinations of the presented embodiments are in particular likewise
covered by the invention.
