U.S. patent application number 11/996912 was filed with the patent office on 2008-07-03 for method for cooling an airflow.
This patent application is currently assigned to Imes Management AG. Invention is credited to Urs Weidmann.
Application Number | 20080156465 11/996912 |
Document ID | / |
Family ID | 35355623 |
Filed Date | 2008-07-03 |
United States Patent
Application |
20080156465 |
Kind Code |
A1 |
Weidmann; Urs |
July 3, 2008 |
Method For Cooling an Airflow
Abstract
A method of cooling a first airstream employs the steps of
dehumidifying a second airstream, injecting water into the
dehumidified airstream so as to cool the second airstream, and
passing the first and the cooled second airstream through a heat
exchanger so as to cool the first airstream. In so doing, the
condensate recovered during the dehumidification of the second
and/or first airstream is used in the injection step.
Inventors: |
Weidmann; Urs; (Zug,
CH) |
Correspondence
Address: |
BROWDY AND NEIMARK, P.L.L.C.;624 NINTH STREET, NW
SUITE 300
WASHINGTON
DC
20001-5303
US
|
Assignee: |
Imes Management AG
Cham
CH
|
Family ID: |
35355623 |
Appl. No.: |
11/996912 |
Filed: |
July 21, 2006 |
PCT Filed: |
July 21, 2006 |
PCT NO: |
PCT/CH06/00385 |
371 Date: |
January 25, 2008 |
Current U.S.
Class: |
165/138 |
Current CPC
Class: |
B60H 1/039 20190501;
Y02B 30/56 20130101; F24F 2003/1435 20130101; Y02B 30/545 20130101;
Y02B 30/563 20130101; F24F 5/0035 20130101; F24F 12/006 20130101;
B60H 3/024 20130101; F24F 1/0007 20130101; Y02B 30/54 20130101 |
Class at
Publication: |
165/138 |
International
Class: |
F24F 5/00 20060101
F24F005/00; F24F 12/00 20060101 F24F012/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 25, 2005 |
EP |
05106803.9 |
Claims
1-9. (canceled)
10. A method for cooling and dehumidifying a first air stream, the
method comprising the steps: A) passing a second air stream through
a first coarse particle filter and a first electro-filter for
cleaning the second air stream and through a first cavity of an
air-dehumidifying apparatus, which is separated by a water vapor
permeable structure from a second cavity of the air-dehumidifying
apparatus, for dehumidifying the cleaned second air stream and
obtaining water as condensate; B) injecting water into the
dehumidified second air stream for cooling the second air stream,
C) passing the first air stream through a second coarse particle
filter and a second electro-filter for cleaning the first air
stream; and D) passing the first air stream cleaned in step C and
the second air stream cleaned, dehumidified and cooled with the
steps A and B through a heat exchanger for cooling the first air
stream, wherein water obtained when dehumidifying the second air
stream in step A is used in step B for injecting.
11. The method of claim 10, wherein the first air stream cleaned
and cooled with steps C and D is passed through a first cavity of a
further air-dehumidifying apparatus, which first cavity is
separated by a water vapor permeable structure from a second cavity
of the further air-dehumidifying apparatus, for dehumidifying the
cleaned and cooled first air stream and for obtaining water as
condensate, and wherein also the water obtained in doing so is used
in step B for injecting.
12. The method of claim 10, wherein free ambient air is
dehumidified in order to obtain further water as condensate for
step B.
13. The method of claim 11, wherein free ambient air is
dehumidified in order to obtain further water as condensate for
step B.
14. An apparatus for cooling a first air stream, comprising a first
coarse particle filter and a first electro-filter for cleaning the
first air stream, a second coarse particle filter and a second
electro-filter for cleaning a second air stream, an
air-dehumidifying apparatus for the cleaned second air stream,
having a first cavity and a second cavity, which are separated from
each other by a water vapor permeable structure, wherein the second
air stream may flow through the first cavity, a condensation water
separator, which is connected via a manifold with the second cavity
of the air-dehumidifying apparatus for the second air stream, pump
means arranged in the manifold, a cooling system, through which the
dehumidified second air stream may flow, a conduit and a pressure
booster pump arranged in the conduit for feeding water obtained in
the condensation water separator to the cooling system, and a heat
exchanger for exchanging heat between the cleaned first air stream
and the cleaned, dehumidified and cooled second air stream.
15. The apparatus of claim 14, further comprising an additional
air-dehumidifying apparatus for the first air stream, having a
first cavity and a second cavity, which are separated from each
other by a water vapor permeable structure, wherein the first air
stream may flow through the first cavity, wherein the second cavity
of the air-dehumidifying apparatus for the first air stream is
connected with the manifold.
16. The apparatus of claim 14, further comprising an additional
air-dehumidifying apparatus for obtaining further water from
ambient air and supplying to the cooling system.
17. The apparatus of claim 15, further comprising an additional
air-dehumidifying apparatus for obtaining further water from
ambient air and supplying to the cooling system.
18. The apparatus of claim 14, further comprising an additional
air-dehumidifying apparatus for the second air stream, having a
first cavity and a second cavity, which are separated from each
other by a water vapor permeable structure, wherein the second air
stream may flow through the first cavity, an additional cooling
system for the second air stream, an additional heat exchanger for
the exchange of heat between the first air stream and the second
air stream.
19. The apparatus of claim 15, further comprising an additional
air-dehumidifying apparatus for the second air stream, having a
first cavity and a second cavity, which are separated from each
other by a water vapor permeable structure, wherein the second air
stream may flow through the first cavity, an additional cooling
system for the second air stream, an additional heat exchanger for
the exchange of heat between the first air stream and the second
air stream.
20. The apparatus of claim 16, further comprising an additional
air-dehumidifying apparatus for the second air stream, having a
first cavity and a second cavity, which are separated from each
other by a water vapor permeable structure, wherein the second air
stream may flow through the first cavity, an additional cooling
system for the second air stream, an additional heat exchanger for
the exchange of heat between the first air stream and the second
air stream.
21. The apparatus of claim 17, further comprising an additional
air-dehumidifying apparatus for the second air stream, having a
first cavity and a second cavity, which are separated from each
other by a water vapor permeable structure, wherein the second air
stream may flow through the first cavity, an additional cooling
system for the second air stream, an additional heat exchanger for
the exchange of heat between the first air stream and the second
air stream.
22. The apparatus of claim 16, further comprising an additional
air-dehumidifying apparatus for the first air stream, with a first
cavity and a second cavity, which are separated from each other by
a water vapor permeable structure, wherein the first air stream may
flow through the first cavity.
23. The apparatus of claim 17, further comprising an additional
air-dehumidifying apparatus for the first air stream, with a first
cavity and a second cavity, which are separated from each other by
a water vapor permeable structure, wherein the first air stream may
flow through the first cavity.
24. Vehicle comprising an apparatus according to claim 16.
25. Vehicle comprising an apparatus according to claim 17.
26. Vehicle of claim 24, wherein the vehicle is a motor vehicle or
a trailer of a motor vehicle or a dormobile or a caravan or a lorry
or a trailer or a ship or an aircraft.
27. Vehicle of claim 25, wherein the vehicle is a motor vehicle or
a trailer of a motor vehicle or a dormobile or a caravan or a lorry
or a trailer or a ship or an aircraft.
Description
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to an apparatus for cooling an
airstream and has the features of the preamble of claim 1.
PRIOR ART
[0002] Dehumidifying systems are known in domestic technology. Here
it is possible to use an apparatus as disclosed by EP 1 521 040.
From an airstream flowing through a first cavity, humidity is
extracted via a water-permeable and/or water vapour-permeable
membrane. Prior to the heat exchange with the airstream to be
cooled and the dehumidified return airstream, a liquid is then
added to this return air and evaporated in order to lower the
temperature of the return airstream upstream of the heat exchanger
(evaporative cooling).
[0003] EP 0 959 307 discloses a sorption plate heat exchanger,
whose dilute sorbent is collected by means of a complex procedure,
reprocessed (desorption by heating and subsequent cooling) and then
passed back to the plate heat exchanger.
[0004] WO 03/091632 discloses a dew point condenser, in which two
airstreams are guided past a heat-conducting wall. In the process,
water is absorbed from the one airstream in a unilateral
hygroscopic coating of the wall and fed back to the medium by
evaporation. This results in cooling of the other airstream behind
the wall.
[0005] U.S. Pat. No. 6,434,963 describes a cooling and heating
apparatus comprising a, central heat exchanger. At the outlets of
the heat exchanger, a closed cooling circuit is provided which
further cools the supply air, the return air being further heated
thereby. In the prior art apparatus, water is added to the spent
compartment air so as to cool it upstream of the heat exchanger.
Downstream of the heat exchanger, more water is added to the return
air, advantageously by means of an evaporative pad, before the
return air passes through the heating section of the cooling
circuit. On the supply-air side, water condensing on the cooling
section of the cooling circuit is collected and is recycled to the
evaporative pad. An external water supply is also present.
[0006] US 2005/056042 describes a similar apparatus as U.S. Pat.
No. 6,434,963, in which water is injected into the return air above
the heat exchanger, thus causing the walls of the heat exchanger to
be wetted. Collecting the water below the heat exchanger permits a
partial water cycle, with the exception of the water vapour
remaining in the return air.
DESCRIPTION OF THE INVENTION
[0007] Based on this prior art, the object of the invention is to
improve an apparatus of the type mentioned at the outset in such a
way that wholly or partially self-sufficient operation of the
apparatus is thereby enabled.
[0008] This object is achieved by an apparatus having the features
of claim and of claim 4.
[0009] Accordingly, a method of cooling a first airstream comprises
the steps of dehumidifying a second airstream, injecting water into
the dehumidified second airstream so as to cool the second
airstream and passing the first and the cooled second airstream
through a heat exchanger so as to cool the first airstream. In the
process of dehumidifying the second airstream, condensate is
recovered which is reused in the injection step.
[0010] Owing to physical givens, injection comprises evaporation of
the injected water.
[0011] For the purpose of increasing self-sufficiency, particularly
in mobile installations: there is the additional option of further
condensate to be injected being recovered by means of dehumidifying
free ambient air.
[0012] An apparatus for cooling a first airstream according to the
present invention comprises an air dehumidifying apparatus for at
least one second airstream having a water-permeable and/or water
vapour-permeable structure which via pumping means is connected to
a condensate separator, a cooling system through which the
dehumidified second airstream can be passed, and a heat exchanger
through which the two airstreams can be passed so as to cool the
first airstream. The water recovered from the condensate separator
is passed into the cooling system for the purpose of injecting it
(evaporation).
[0013] In a further air dehumidifying apparatus, of the apparatus
according to the invention, further condensate can be recovered
from the cooled first airstream.
[0014] An additional air dehumidifying apparatus can be used to
recover further condensate from the ambient air.
[0015] The additional apparatus can be arranged on a vehicle. In
this arrangement, the airstream along the additional air
dehumidifying apparatus is generated by moving the vehicle.
[0016] The vehicle is preferably a motor vehicle or a trailer of a
motor vehicle, particularly preferably a dormobile, a caravan, a
lorry, a trailer, a ship or an aircraft.
BRIEF DESCRIPTION OF THE DRAWING
[0017] The invention is explained below in more detail with
reference to the drawing, in which FIG. 1 shows a schematic
depiction of an embodiment of the present invention.
DESCRIPTION OF AN EMBODIMENT
[0018] FIG. 1, in a schematic depiction, shows an apparatus
according to the present invention. The function of the apparatus
according to the invention is explained with reference to this
schematic depiction. The apparatus for cooling compartment air is
provided with a multiplicity of individual appliances which are
known to those skilled in the art and are therefore not discussed
here in any detail.
[0019] In an airstream referred to as the first airstream, outside
air 50 is passed as supply air 51, via various elements into a
compartment 60. The outside air 50, which in the summer often has
an outside temperature that it would be desirable to lower, is
typically passed via a coarse particle filter 38 and/or an
electrostatic filter 39 into a heat exchanger 40, a possible design
of the heat exchanger being that of a plate heat exchanger in
accordance with WO 2004/085946. In the heat exchanger 40, the
outside air 50 undergoes cooling by the cooled airstream 55''
advantageously passed countercurrently, and re-emerges as cooled
airstream 50'. The cooled airstream 50' is then advantageously
passed into a first air dehumidifying apparatus 1. In this first
air dehumidifying apparatus 1, humidity is extracted from the
cooled airstream 50' which now, compared with the warmer outside
air 50, has a higher relative atmospheric humidity, and the cooled
airstream 50' leaves the air dehumidifying apparatus 1 as a cooled
and dehumidified airstream 50''. By means of a fan 41, the cooled
and dehumidified airstream 50'' is supplied as supply air 51 to an
advantageously closed compartment 60 in which the desired climatic
conditions are achieved. Accordingly, the supply air 51 has a lower
temperature than the outside air 50.
[0020] In an airstream referred to as the second airstream, return
air 55 from a compartment 60 is discharged as exhaust air 56 to the
environment via various elements to be described hereinafter. The
return air 55, which has an interior temperature, is typically
passed from the closed compartment 60 through a coarse particle
filter 38 and/or an electrostatic filter 39. The return air 55
enters a second air dehumidifying apparatus 2 and leaves this as a
dehumidified airstream 55'. By means of a fan 41, the dehumidified
airstream 55' is fed to a cooling system 20. In the cooling system,
the dehumidified airstream 55' is cooled. Consequently, a cooled
airstream 55'' escapes from the cooling system. In the heat
exchanger 40, heat exchange takes place between the cooled
airstream 55'' and the warm outside air 50. After heat exchange has
taken place, the now warmer airstream 55'', which previously has
been cooled leaves the heat exchanger as exhaust air 56 which is
then discharged to the environment.
[0021] The two air dehumidifying apparatuses 1, 2 can be of a
design in accordance with EP 1 521 040 or a comparable apparatus.
The air dehumidifying apparatuses 1, 2 for example comprise a first
cavity 4 in each case, which is separated from a second cavity 5 by
means of a water-permeable and/or water vapour-permeable membrane
3. The abovedescribed airstreams in each case flow through a
separate first cavity 4.
[0022] In other embodiments, two separate air dehumidifying
apparatuses 1, 2 can be provided, or just the dehumidifying
apparatus 2 is provided for the second airstream 55. As indicated
below, a further air dehumidifying apparatus not shown in the
drawings can also be provided, which operates on ambient air, i.e.
dehumidifies the latter. The purpose of this, however, is not the
dehumidified ambient air but the recovery of condensate. This can
be achieved by means of a separate condensation water separator or
the condensation water separator 11 explained in conjunction with
the dehumidifying apparatuses 1, 2.
[0023] By means of a partial vacuum, e.g. generated by a vacuum
pump 10, a partial vacuum is generated in a manifold 6 and in the
second cavity 5 of the air dehumidifying apparatus 1, 2. Via this
manifold 6, which is connected to the second cavity 5 of the air
dehumidifying apparatuses 1, 2, this more humid air is discharged.
The partial vacuum causes a mixture 100 of air and water vapour to
be drawn into the condensation water separator 11. By means of the
condensation water separator 11, the mixture 100 is separated into
air 101 and water 102. The air 101 is discharged into the
environment, and the water 102 is fed via a conduit 19 to a
pressure booster pump 13. Via a further conduit section 14, the
pressurized water 103 is supplied to the cooling system 20.
[0024] In the cooling system 20, of a design, for example, in
accordance with WO 2004/085946, the pressurized water 103 is
atomized by means of one or more nozzles, increasing the humidity
of the dehumidified airstream 55'. In the process, the relative
humidity of the exhaust air increases, and as a result of the
evaporation heat to be absorbed the temperature of the dehumidified
airstream 55' drops, resulting in the cooled airstream 55''. Excess
water is discharged to the environment. Alternatively, it can be
collected with the intention of recycling it into the cooling
system 20.
[0025] Recovering condensation water 102 by dehumidifying an
airstream 50' and/or 55 and subsequently recycling it into the
cooling system 20, enables wholly or partially self-sufficient
operation of the apparatus according to the present invention.
[0026] Installing an additional air dehumidifying apparatus (not
shown in the drawings) allows the recovery of further condensate.
In this arrangement, the apparatus does not include the cavity 4,
the membrane 3 therefore being directly contiguous to an airstream.
This apparatus is particularly advantageous if the apparatus is
mounted on a motor vehicle or a trailer of a motor vehicle, for
example a dormobile, a caravan, a lorry, a trailer, or an aircraft.
The airstream in this case is an airstream flowing past which is
generated by the relative wind of the vehicle. In doing so
condensate for injection purposes is recovered from the free
ambient air.
[0027] All the said airstreams, apart from the airstream flowing
past, are guided in conduits or ducts known to those skilled in the
art.
[0028] In winter, the installation can also be used to heat and
humidify the airstream 50, 50', 50''. The airstream 55', 55'' is
then not cooled in the cooling system 20. In the heat exchanger 40,
the airstream 50 can accordingly be heated by means of warmer
return air 55''. Moreover, humidity is abstracted from the return
air 55 in the second air dehumidifying apparatus 2 and is fed via
the manifold 6 into the first air dehumidifying apparatus 1. Via
the first air dehumidifying apparatus 1, humidity of the airstream
50' is augmented. The apparatus can be combined with a caravan
heating installation or a motor vehicle heating installation.
[0029] The apparatus according to FIG. 1 can be cascaded in a
simple manner. The simplest cascade is achieved by arranging onto
the ducts guiding the airstreams 50 and 56 a further apparatus
inclusively comprising the filters 38, 39 and the heat exchanger 40
as shown in the depiction on the left-hand side of FIG. 1 and up to
and including fan 41 and filters 38, 39 as shown on the right-hand
side of FIG. 1 in such a manner that the duct for the supply air 51
is connected to the said duct 50 and the duct of the return air 55
is connected to the exhaust air of the previous apparatus. It is
thus possible, in a number of steps, to all in all lower the
temperature to a greater extent. Each of the apparatuses can then
be self-sufficient apart from its power supply leads, the ducts 101
for the discharge of the air are advantageously combined. The
advantage of this cascading arrangement is its simplicity, since
apparatuses of identical construction can be used. Should a unit
fail, operation of the apparatus as a whole is not affected per se,
since, for example, the fans 41 of the other apparatuses will
continue to maintain air movement and, if a water circuit were to
fail, cooling of the other cascade elements continues to
function.
[0030] In a simpler cascading arrangement, cascading is limited to
the air dehumidifying apparatus 2 together with the injection
system 20 and the heat exchanger 40. Fans 41, filters 38, 39 and
water separator 11 likewise may be provided as a single item for
the entire apparatus. In that case, the return air 55 then
successively passes through the assemblies 2, 20 and 40, whereas
the outside air 50 in each case is passed solely through the second
duct of the heat exchanger 40, optionally also through the air
dehumidifying apparatus 1.
LIST OF REFERENCE SYMBOLS
[0031] 1 Air dehumidifying apparatus [0032] 2 Air dehumidifying
apparatus [0033] 3 Water-permeable and/or water vapour-permeable
membrane [0034] 4 First cavity [0035] 5 Second cavity [0036] 6
Manifold [0037] 10 Vacuum pump [0038] 11 Condensation water
separator [0039] 12 Conduit [0040] 13 Pressure booster pump [0041]
14 Conduit [0042] 20 Cooling system [0043] 38 Coarse particle
filter [0044] 39 Electrostatic filter [0045] 40 Heat exchanger
[0046] 41 Fan [0047] 50 Outside air [0048] 50' Cooled airstream
[0049] 50'' Dehumidified, cooled airstream [0050] 51 Supply air
[0051] 55 Return air [0052] 55' Dehumidified airstream [0053] 55''
Cooled airstream [0054] 56 Exhaust air [0055] 60 Compartment [0056]
100 Mixture of air and condensation water [0057] 101 Air [0058] 102
Water [0059] 103 Pressurized water
* * * * *