U.S. patent application number 15/027197 was filed with the patent office on 2016-09-01 for system and method for air handling and air conditioning.
This patent application is currently assigned to COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES AL TERNATIVES. The applicant listed for this patent is COMMISSARIAT L'ENERGIE ATOMIQUE ET AUX ENERGIES AL TERNATIVES. Invention is credited to Stephane COLASSON, Mathieu MARIOTTO.
Application Number | 20160252262 15/027197 |
Document ID | / |
Family ID | 49911680 |
Filed Date | 2016-09-01 |
United States Patent
Application |
20160252262 |
Kind Code |
A1 |
MARIOTTO; Mathieu ; et
al. |
September 1, 2016 |
SYSTEM AND METHOD FOR AIR HANDLING AND AIR CONDITIONING
Abstract
A system for air handling and air conditioning to supply cool
air inside a volume, the system including at least one enthalpy
exchanger module including a dual airflow, enabling a heat transfer
and a water vapor transfer between both airflows, the system
configured to operate according to a cooling mode of the volume in
which both airflows are respectively made of an outside airflow to
be introduced into the volume, and a cooler dryer foul airflow,
coming from inside of the volume. The system further includes: a
mechanism enabling relative humidity of the outside airflow at an
inlet of the enthalpy exchanger module to be determined; and a
controller configured to command a heat supply to the outside
airflow before it enters the module, when the relative humidity
thereof exceeds a predetermined value.
Inventors: |
MARIOTTO; Mathieu; (La
Motte-Servolex, FR) ; COLASSON; Stephane; (Voreppe,
FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
COMMISSARIAT L'ENERGIE ATOMIQUE ET AUX ENERGIES AL
TERNATIVES |
Paris |
|
FR |
|
|
Assignee: |
COMMISSARIAT A L'ENERGIE ATOMIQUE
ET AUX ENERGIES AL TERNATIVES
Paris
FR
|
Family ID: |
49911680 |
Appl. No.: |
15/027197 |
Filed: |
October 7, 2014 |
PCT Filed: |
October 7, 2014 |
PCT NO: |
PCT/EP2014/071380 |
371 Date: |
April 4, 2016 |
Current U.S.
Class: |
62/90 |
Current CPC
Class: |
F24F 11/83 20180101;
F24F 12/00 20130101; F24F 2012/005 20130101; F24F 12/002 20130101;
F24F 2013/221 20130101; F24F 2110/22 20180101; F24F 11/84 20180101;
F24F 12/003 20130101; F25B 5/04 20130101; F24F 2110/20 20180101;
F25B 6/04 20130101; F24F 3/147 20130101; F24F 13/22 20130101; F24F
12/006 20130101; F24F 3/153 20130101; F24F 11/30 20180101; F24F
12/001 20130101 |
International
Class: |
F24F 3/147 20060101
F24F003/147; F24F 13/22 20060101 F24F013/22; F24F 11/00 20060101
F24F011/00; F24F 3/153 20060101 F24F003/153 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 9, 2013 |
FR |
13 59815 |
Claims
1-10. (canceled)
11. A system for air handling and air conditioning comprising: at
least one enthalpy exchanger module including a dual airflow
enabling a heat transfer and a water vapor transfer between two
airflows, respectively made of a first airflow and a second airflow
having a temperature and an absolute humidity lower than those of
the first flow; means for determining relative humidity of the
first airflow at an inlet of the enthalpy exchanger module; control
means configured to command a heat supply to the first airflow
before the first airflow enters the enthalpy exchanger module, when
the relative humidity exceeds a predetermined value; a vapor
compression refrigerating unit including an evaporator and a
condenser through which the first airflow can pass after it leaves
the enthalpy exchanger module; and wherein the system is configured
so that the heat supply comes from the heating unit, or from part
of a refrigerant fluid passing through the heating unit.
12. The system for air handling and air conditioning according to
claim 11, further comprising a secondary exchanger configured to
provide the heat supply to the first airflow.
13. The system for air handling and air conditioning according to
claim 11, comprising a plurality of enthalpy exchanger modules
arranged in series and through which the first airflow and the
second airflow successively pass.
14. The system for air handling and air conditioning according to
claim 13, configured so that determining the relative humidity can
be performed for at least one enthalpy exchanger module, and so
that the first airflow can be heated at least before the first
airflow enters one of the enthalpy exchanger modules.
15. The system for air handling and air conditioning according to
claim 13, wherein the control means is configured to command a heat
supply to the first airflow before the first airflow enters each of
the enthalpy exchanger modules, for which the relative humidity
determined at the inlet of the module exceeds a predetermined
value.
16. The system for air handling and air conditioning according to
claim 11, configured to circulate the first airflow and the second
airflow countercurrently in the enthalpy exchanger module.
17. The system for air handling and air conditioning according to
claim 11, wherein each enthalpy exchanger module is a module of a
waterproof-breathable membrane.
18. The system for air handling and air conditioning according to
claim 11, comprising plural enthalpy exchanger modules successively
arranged along a stacking direction, any two directly consecutive
modules having a contact area on either side of which two
intermediate passage chambers of the airflows are respectively
arranged, each being partly delimited by an airflow outlet of one
of both modules and an airflow inlet of the other of both
modules.
19. The system for air handling and air conditioning according to
claim 11, configured to supply cool air inside a volume or a
building, wherein the first airflow is an airflow to be introduced
into the volume or an outside airflow, and wherein the second
airflow is an airflow coming from inside of the volume, or to a
foul airflow in the case the volume is a building.
20. A method for air handling and air conditioning, the method
being implemented using a system according to claim 11, and
including determining the relative humidity of the first airflow at
the inlet of the enthalpy exchanger module, and then, when the
relative humidity exceeds a predetermined value, commanding a heat
supply to the first airflow before the first airflow enters the
enthalpy exchanger module.
Description
[0001] The invention relates to the field of systems and methods
for air handling and air conditioning, for example for buildings
exposed to hot humid climates of the type faced in South-East Asia.
Nevertheless, other applications are possible. For example, the
invention can also be applied to air volumes involved in industrial
applications and comprising air drying issues, such as in the
paper, food and micro-electronics industry.
[0002] The invention more precisely relates to such systems fitted
with dual airflow exchangers, of the type enabling a heat transfer
as well as a humidity/water vapour transfer between both airflows
passing through the exchanger. Such an exchanger providing this
dual transfer is also commonly referred to as a "total heat
exchanger" or "enthalpy heat exchanger".
[0003] The invention therefore applies to air handling and air
conditioning for buildings, preferably for housing and service
industries. The exchanger thus not only ensures a heat transfer
between the foul airflow and the outside airflow, but also a water
vapour transfer between both flows, from the most humid environment
to the driest environment.
[0004] In hot humid climates, the outside airflow, also referred to
as fresh airflow, can have a high temperature, for example around
30 to 35.degree. C., and a strong relative humidity, for example
around 90 to 95%. Under these conditions, water vapour transfer
therefore occurs from the outside airflow to the foul airflow.
Nevertheless, when the relative humidity of the outside airflow is
very high, there is a risk of condensation within the exchanger,
which is detrimental to its proper operation, its reliability and
health security of the process. Indeed, even if the water vapour
transfer between both flows passing through the exchanger
contributes to reducing the absolute humidity of the outside
airflow, the relative humidity is on the other hand increased by
cooling this same outside airflow in the exchanger. In this
connection, it is reminded that the absolute humidity corresponds
to the water vapour concentration per kilogram of dry air, whereas
the relative humidity corresponds to the ratio of partial vapour
pressure to the saturation vapour pressure (pressure from which air
can no longer contain more vapour, otherwise the latter
condenses).
[0005] In prior art, there are several solutions implementing
enthalpy exchangers, which can for example be installed upstream of
a vapour compression refrigerating unit. By way of indication,
these solutions are alternatives to the use of dehydrating wheels
also known from prior art, but belonging to a field far removed
from the one of the invention.
[0006] Regarding the enthalpy exchanger solutions, few of them
resolve the issue of the condensation risk inside the exchanger. A
solution is however provided in EP 2 498 013, which discloses the
possibility of bypassing the enthalpy exchanger in case of an
outside airflow having a too high relative humidity. Nevertheless,
by denying the passage thereof through the exchanger, the system
undergoes a significant efficiency loss, since the energy
associated with the foul airflow remains unused.
[0007] So, there is a need for optimizing these systems for air
handling and air conditioning with enthalpy exchangers, especially
in order to deal with the condensation risks of the highly humid
outside airflow.
[0008] To address this issue, the object of the invention is first
a system for air handling and air conditioning comprising at least
one dual airflow enthalpy exchanger module enabling a heat transfer
and a water vapour transfer between both airflows, respectively
made of a first airflow and a second airflow having a temperature
and an absolute humidity lower than those of the first airflow.
[0009] According to the invention, the system further includes:
[0010] means for determining the relative humidity of the first
airflow at the inlet of said enthalpy exchanger module; and [0011]
control means configured to command a heat supply to the first
airflow before it enters said enthalpy exchanger module, when the
relative humidity exceeds a predetermined value.
[0012] The originality of the invention thus consists in heating,
if need be, the first airflow which would be in a condition too
close to the saturation curve. It is therefore cleverly performed a
rising of the hottest airflow temperature. By a simple rise of its
temperature, this first airflow has its relative humidity
decreased, and therefore becomes less subject to the condensation
risk in the exchanger module. This solution is advantageous on the
one hand in that it avoids the bypass of the exchanger as suggested
in prior art, and on the other hand in that the heat supply,
required for maintaining the airflow at a relative humidity lower
than a predetermined value, can be small.
[0013] Preferably, the system further includes a vapour compression
refrigerating unit fitted with an evaporator and a condenser
through which the first airflow after it leaves said enthalpy
exchanger module is intended to pass, and the system is designed so
that said heat supply comes from said heating unit, and preferably
from part of a refrigerant fluid passing through this unit.
Alternatively, the heat supply could come from the heat generated
by said condenser of the refrigerating unit in operation. The heat
supply would then be performed from a refrigerant fluid of the
condenser, this fluid being usually air.
[0014] Other solutions are worth considering to provide this heat
supply, preferably from renewable energies. Typically, it can be
solar collectors, or even resistive elements. The above-described
solutions aiming at drawing energy at the refrigerating unit is
particularly advantageous in that it enables all or part of the
unavoidable energies of the thermodynamic cycle to be recovered
within such a refrigerating unit.
[0015] Preferably, the system comprises a secondary exchanger
designed to provide said heat supply to the first airflow,
preferably an outside airflow.
[0016] To make this secondary exchanger, any technology is possible
as a function of the fluid used, namely a liquid, gas fluid or a
mixture of both, and as a function of the type of energy, namely a
sensible, latent or joule effect energy. In a possible embodiment,
said first airflow and part of the refrigerant fluid which flows in
the unit pass through the secondary exchanger, this heated fluid
leaving the compressor actually enabling the necessary calories to
be brought to the first airflow. Nevertheless, without departing
from the scope of the invention, any other way of extracting the
heat generated within the refrigerating unit is possible, in order
to bring it towards the first airflow to be heated.
[0017] Preferably, the system comprises a plurality of enthalpy
exchanger modules arranged in series through which said first
airflow and said second airflow successively pass.
[0018] Preferably, the system is then designed so that determining
the relative humidity can be performed for at least one enthalpy
exchanger module, and so that the first airflow can be heated at
least before it enters one of said enthalpy exchanger modules.
[0019] Even more preferentially, said control means are designed to
command a heat supply to the first airflow before it enters each of
said enthalpy exchanger modules, for which the relative humidity
determined at the inlet of the module exceeds a predetermined
value.
[0020] In this instance, the relative humidity is therefore
determined at the inlet of each of the modules forming together the
enthalpy exchanger. The heat supply is then individually controlled
module by module, by comparison with the predetermined value which
is preferentially identical for all the exchanger modules, but
which could nevertheless differ as a function of the modules.
[0021] Other alternatives are possible and covered by the present
invention. For example, determining the relative humidity could
only be made for a restricted number n of modules, greater than or
equal to one, whereas the heat supply could be applied at the inlet
of a number m of modules greater than or equal to number n. By way
of example, only by determining the relative humidity of the first
airflow at the inlet of the first enthalpy exchanger module, the
heat supply could be commanded at the inlet of one or several of
the modules forming the enthalpy exchanger.
[0022] In every case, the heat supply can be regulated, for example
stopped only when the relative humidity reaches the predetermined
value, or the command can simply lead to the supply of a determined
amount of heat, possibly as a function of the determined value of
relative humidity.
[0023] In every case, multiplying the exchanger modules, and
heating the outside airflow successively when it enters different
exchanger modules, contributes to rationalizing the use of heat
supplied to the outside airflow and to increase the maximum value
of relative humidity allowed within the modules. In this
connection, it is noted that with generally variable inlet
conditions in the different modules, the cascade configuration
enables a finer adjustment of the amounts of heat to be used, a
minimum safety margin having to be taken into account, hence the
notion of rationalizing the used energy. This contrasts with the
single module configuration where a more significant safety margin
would have to be used to be able to adapt to every possible
case.
[0024] In this system which enables the energy to be used
rationally while avoiding pernicious occurrences of condensation in
the enthalpy exchanger, it is preferentially provided to
recirculate the outside airflow and the foul airflow
countercurrently in the enthalpy exchanger module. Even if a
cocurrent solution is possible, the countercurrent solution is
preferred for an even more rational use of the drawn energy so as
to heat the outside airflow.
[0025] Preferably, each enthalpy exchanger module is a module of
the waterproof-breathable membrane type, that is liquid water and
air tight and water vapour permeable, whether it is a plate,
tubular or other exchanger.
[0026] Preferably, the system comprises several enthalpy exchanger
modules successively arranged along a stacking direction, any two
directly consecutive modules having a contact area on either side
of which two intermediate passage chambers of airflow are
respectively arranged, each being in part delimited by an airflow
outlet of one of both modules and an airflow inlet of the other of
both modules.
[0027] Preferably, the system for air handling and air conditioning
is preferentially intended to supply cool air inside a volume,
preferably a building, said first airflow is an airflow intended to
be introduced into the volume, preferably an outside airflow, and
the second airflow is an airflow coming from the inside of said
volume, corresponding to a foul airflow in the case where the
volume is a building.
[0028] The object of the invention is also a method for air
handling and air conditioning, the method being implemented using a
system such as described above and including a step for determining
the relative humidity of the first airflow at the inlet of said
enthalpy exchanger module, and then, when the relative humidity
exceeds a predetermined value, a step for commanding a heat supply
to the first airflow before it enters said enthalpy exchanger
module.
[0029] Further advantages and features of the invention will appear
in the non-limiting detailed description thereafter.
[0030] This description will be made with reference to the
accompanying drawings among which:
[0031] FIG. 1 shows a schematic view of a system for air handling
and air conditioning according to a preferred embodiment of the
invention;
[0032] FIG. 2 shows a view similar to that of FIG. 1, in which the
enthalpy exchanger has a different design with several modules;
[0033] FIG. 3 shows a chart schematizing the control logic provided
by the control means fitting the system for air handling and air
conditioning shown in FIG. 2;
[0034] FIG. 4 is a schematic view similar to that of FIG. 1, in
which the enthalpy exchanger comprises four modules placed in
series;
[0035] FIG. 5 shows a psychrometric chart on which alphabetic
references have been inscribed, these references corresponding to
those indicated in the view of FIG. 4; and
[0036] FIG. 6 shows a more detailed perspective view of an enthalpy
exchanger embodiment, intended to fit a system for air handling and
air conditioning according to the invention.
[0037] First with reference to FIG. 1, it is shown a system for air
handling and air conditioning 100, intended to supply cool air
inside a building 200, preferably intended to be exposed to a hot
humid climate, such as the one faced in South-East Asia. The system
100 first comprises an enthalpy exchanger 2 as well as a vapour
compression refrigerating unit 4, interposed between this exchanger
2 and the building 200. Control means are associated with the
enthalpy exchanger 2, and also possibly with the vapour compression
refrigerating unit 4.
[0038] The enthalpy exchanger 2 is of the conventional type, that
is a first outside airflow F1 and a second foul airflow F2 coming
from the inside of the building 200 are advantageously intended to
pass through it countercurrently, and having a temperature and an
absolute humidity lower than those of the first outside airflow F1.
Here, the exchanger 2 therefore guarantees a heat transfer between
the foul airflow F2 and the outside airflow F1. In other words, the
exchanger is provided to use the coolness contained in the foul
airflow F2 in order to cool the hot outside airflow F1. It is of
course noted that to transfer sensible heat from the flow F1 to the
cooler flow F2, the consequence is a lowering of the temperature of
the hot airflow F1 coming from the outside.
[0039] In parallel, the enthalpy exchanger 2 is provided to
transfer part of the water vapour contained in the outside airflow
F1 towards the foul airflow F2 having a lower water vapour
concentration per kilogram of dry air (absolute humidity) when it
leaves the building 200. [0040] In this operating mode of the
system 100, corresponding to a cooling mode of the building 200,
the outside airflow F1 leaving the enthalpy exchanger 2
successively passes through the evaporator 10 and the condenser 12
of the vapour compression refrigerating unit 4. In a conventional
manner known from those skilled in the art, this unit 4 comprises a
coolant/refrigerant fluid 14 which successively flows in a
compressor 16, the condenser 12, an expansion valve 18 and the
evaporator 10, before being redirected towards the compressor
16.
[0041] The outside airflow F1 first passes through the evaporator
10 in order to be cooled, humidity saturated, condensed and in
order to reach the appropriate absolute humidity level for air
handling, before passing through the condenser 12 in order to
undergo therein a temperature increase accompanied with a relative
humidity decrease, its absolute humidity remaining constant. This
enables the outside airflow F1 to be brought under good humidity
and temperature conditions inside the building 200.
[0042] Still with reference to FIG. 1, it is noted that one of the
features of the invention is that the system further includes means
20 enabling the relative humidity of the outside airflow F1 at the
inlet of the exchanger 2 to be determined. These means can be of
any design considered as appropriate by those skilled in the art,
such as a humidity sensor. As a function of this determination
which is communicated to the control means 6, the latter are
configured to command a heat supply to the outside airflow F1
before it enters the enthalpy exchanger 2, when this predetermined
value of relative humidity exceeds a predetermined value.
[0043] The predetermined threshold value of relative humidity from
which a sensible energy supply is activated, can be defined based
on the sizing data of the enthalpy exchanger and on the knowledge
of the enthalpy efficiency of the latter. This enthalpy efficiency
depends on the operating conditions, the geometric data of the
exchanger and the technology used. Thus, in the case of a
waterproof-breathable membrane exchanger, it depends on the
physical properties of said membrane, specifically those related to
the water vapour transfer, such as the fickian diffusion
coefficient, the maximum water intake of the membrane, and the
sorption constant.
[0044] By proceeding this way, it is possible to increase the
temperature of the outside airflow F1 before it enters the
exchanger 2, so as to limit the condensation risks detrimental to
its proper operation.
[0045] In the preferred embodiment depicted in FIG. 1, the heat
supply comes from the refrigerant fluid part of which is diverted
after it leaves the compressor 16. To create this diversion, it is
provided a circuit 26 with a tapping 26a upstream of the condenser
12 enabling part of the refrigerant fluid 14 to be conveyed up to
the inlet of a secondary exchanger 22. At the outlet of this
exchanger 22, the refrigerant fluid is redirected by the circuit 26
up to a second tapping 26b downstream of the condenser 12, for
being reintroduced in the refrigerating unit 4.
[0046] The secondary exchanger 22 has therefore passing through it
on the one hand the outside airflow F1, and on the other hand part
of the refrigerant fluid 14 drawn downstream of the compressor 16.
The flow rate of the refrigerant fluid passing through the circuit
26 is controlled by a valve 28, controlled by the means 6. Of
course, any design considered as appropriate is worth considering
for the secondary exchanger 22, for example of the finned tube
exchanger type.
[0047] It is noted that in the case where the energy drawn in the
direction of the secondary exchanger 22 does not make it possible
to reach the appropriate thermodynamic conditions before expanding
the fluid in the expansion valve 18, it is provided, upstream
thereof, a unit heater 27 forming an auxiliary condenser. This unit
heater 27 is therefore intended to have passing through it on the
one hand the refrigerant fluid 14 after it leaves the condenser 12,
and on the other hand an outside airflow F3.
[0048] The amount of heat brought to the secondary exchanger 22 can
be regulated, for example stopped only when the relative humidity
value of the flow F1 determined by the sensor 20 reaches the
predetermined value, which can possibly be input by an operator as
a function of the encountered needs. This value can also take into
account the design of the exchanger, according to its sensitivity
to humid airflows regarding condensation risks. It is noted that
this sensitivity is largely related to the transfer efficiency of
water vapour through the membrane.
[0049] With reference now to FIG. 2, it is shown an alternative
implementation in which the enthalpy exchanger 2 is made by a
plurality of enthalpy exchanger modules M1, M2, . . . , Mi, . . . ,
Mn, these modules being arranged in series and having successively
passing through it the outside airflow F1 and the foul airflow F2
always flowing countercurrently in each of the modules. In this
example, a secondary exchanger 22 is associated with each module,
present upstream of the inlet of the outside airflow F1. These
exchangers are controlled by the means 6 via the valves 28, and
they are also each associated with a relative humidity sensor 20
delivering the determined values to these same means 6.
[0050] The advantage of such a configuration is that it can bring
heat to the outside airflow F1 before it enters each module, that
is performing successive heat supplies before it passes in each
module.
[0051] As schematized in FIG. 3 showing the control logic
associated with each of the exchanger modules, it is for example
provided, for each module Mi, that determining the relative
humidity hri at the inlet of the relevant exchanger module Mi is
carried out using the sensor 20. If this value hri is greater than
a reference value of relative humidity hrr corresponding to the
above-mentioned predetermined value, then the outside airflow F1 is
heated by the associated secondary exchanger 22. This is made by
controlling the valve 28 ensuring the flow of the refrigerant fluid
14 in the secondary exchanger 22. In the opposite case where the
value hri remains lower than the value hrr, no operation is
undertaken, that is the outside airflow F1 is not heated before it
is introduced in the following module.
[0052] The reference value of relative humidity hrr can be the same
at each exchanger module Mi, or can be different. By way of
indicating example, this value is preferentially the same for all
the exchanger modules, when the latter have an identical or similar
design.
[0053] This way of proceeding makes it possible to keep permanently
the outside airflow F1 with a relative humidity lower than the
reference relative humidity hrr considered as critical for the
enthalpy exchanger modules, simply by delivering successive heat
supplies, with a small energy amount.
[0054] The embodiment of FIG. 4 is similar to that presented in
FIG. 2, in that it has an enthalpy exchanger 2 with several
successive modules M1, M2, M3, M4 arranged in series.
[0055] In this FIG. 4, several reference points of the foul airflow
F2 and of the outside airflow F1 have been identified, at different
locations along their paths between the enthalpy exchanger 2 and
the building 200. These same references have been inscribed on the
psychrometric chart of FIG. 5, informing about the air condition at
each of these locations.
[0056] Also, with reference both to FIGS. 4 and 5, it is indicated
that the outside airflow F1 at the point A, corresponding to the
inlet of the exchanger 2, has a high temperature and a high
relative humidity, expressing the hot humid climatic conditions of
the outside air.
[0057] Before being introduced in the first module M1, the flow F1
is heated by the secondary exchanger 22 when its relative humidity
exceeds the reference relative humidity. This heating is expressed
by the line AA' on the chart, the point A' corresponding to the
inlet of the first exchanger module M1. Within this module, the
flow F1 is cooled and also looses its absolute humidity, which
urges it to approach the saturation curve depicted in dotted lines
in FIG. 5. Point A1 shows the condition of the airflow F1 at the
outlet of the first module M1, before it enters the second module
M2, and before its potential heating prior to its introduction in
this same module M2. In a similar way to that described above, the
airflow F1 is here again heated before it enters the second module
M2, at a point A'1 from which it penetrates this second module M2
in order to be cooled therein and discharged from part of its
humidity, until it gets out at the point A2 at which it is in a
condition close to its saturation curve, as shown in FIG. 5.
Analogous phenomena are observed before and during the passage of
this flow F1 through the third module M3 and the fourth module M4,
which explains the zigzag/cascade chart between the points A and B,
respectively corresponding to the inlet points of the flow F1 in
the enthalpy exchanger 2, and to the outlet point of this same flow
F1 from the exchanger.
[0058] When the flow F1 is extracted from this exchanger 2, it
therefore passes through the evaporator 10 up to a point C, this
passage first leading to a temperature decrease bringing the flow
F1 to its saturation curve, which it follows until it reaches its
minimum temperature at the point C at which it also has the desired
absolute humidity level. Then, the passage of the flow F1 through
the condenser 12 causes it to be heated at the desired temperature
to enter the building 200, and to be positioned at a relative
humidity level also corresponding to the desired needs for the
volume of air to be conditioned (relative to the thermal comfort
specifications).
[0059] By way of indicative example, with this operating mode, the
outside air can arrive at a temperature of 35.degree. C. and a
relative humidity of 90% before entering the enthalpy exchanger 2,
whereas the foul airflow leaving the building 200 at the point E
can have a temperature in the order of 22.degree. C. and a relative
humidity of about 50%. Also, on the psychrometric chart of FIG. 5,
the line segment between points D and E may symbolize the evolution
of air during its passage in the building 200, with an increase of
its temperature as well as an increase of its absolute humidity
level. These values related to the foul airflow F2 continue to
increase between points E and F, corresponding to the passage of
this flow F2 through the enthalpy exchanger 2, countercurrently
with the outside airflow F1.
[0060] With reference now to FIG. 6, it is shown an exemplary
implementation of an enthalpy exchanger 2 having a clever design,
and comprising 5 modules placed in series, referenced M1 to M5. As
in the other above-described embodiments, the exchanger modules M1
to M5 have a design with plates and waterproof-breathable
membranes, known from those skilled in the art. Such exchangers are
for example described in FR 2 965 897.
[0061] Indeed, this design relies on the stacking of plates along a
direction 31 orthogonal to a direction 30 along which the modules
succeed each other. In this embodiment, the modules are in contact
in twos along the direction of their stacking 30. Also, two
directly consecutive modules define together, at their median part,
a contact area 34 on either side of which two intermediate passage
chambers of airflow are arranged. There are first an intermediate
passage chamber of the airflow F1, referenced 36, and also an
intermediate passage chamber of the airflow F2, referenced 38.
[0062] As can be seen in FIG. 6, the chambers 36 are arranged
staggered to each other, and the chambers 38 are also arranged
staggered to each other. Each chamber 36 houses a secondary
exchanger 22, which has pipes 40 for feeding and draining the
refrigerant fluid, which passes through the exchanger 2 to go
towards the condenser fitting the refrigerating unit of the system.
Here, each enthalpy exchanger module is in the general shape of a
straight prism with a hexagonal base or a diamond shaped base.
Consequently, each intermediate chamber 36, 38 is in the general
shape of a triangular section, a leg of the triangle being defined
by an inlet of airflow of one of the modules, another leg of the
triangle being defined by an outlet of airflow of the other of the
modules, and the third leg corresponding to a casing 44 laterally
running along the exchanger along the direction 30. Preferably,
several casings 44 are formed by a same and single plate.
[0063] On the other hand, although not represented, upper and lower
casings also cover the modules M1 to M5, especially making it
possible to make the intermediate chambers 36, 38 independent of
one another. Of course, various modifications can be brought by
those skilled in the art to the invention which has just been
described, only by way of non-limiting examples. In particular, the
above-described application relates to the cool air supply of any
building, but the invention can more generally apply to the supply
of volumes of air to be handled in the field of industrial
processes, such as the paper, food or micro-electronics
industry.
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