U.S. patent number RE39,288 [Application Number 10/059,826] was granted by the patent office on 2006-09-19 for heat pump system and method for air-conditioning.
Invention is credited to Gad Assaf.
United States Patent |
RE39,288 |
Assaf |
September 19, 2006 |
Heat pump system and method for air-conditioning
Abstract
There is provided a heat pump system including two (4,6), at
least similar units in fluid communication with each other, each
unit having a housing (8,8'), a first air/brine heat exchanger
(12,12'), a second brine/refrigerant heat exchanger (24,24'), a
brine inlet (10,10') for applying brine onto at least one of the
heat exchangers, a brine reservoir (14,14') and a pump (28) for
circulating the brine from the reservoir to the inlet. The first
and second heat exchangers are in closed loop fluid communication
with each other and have a compressor (44) for circulating a
refrigerant therethrough in selected directions.
Inventors: |
Assaf; Gad (Rehovot 76408,
IL) |
Family
ID: |
26323035 |
Appl.
No.: |
10/059,826 |
Filed: |
April 9, 1996 |
PCT
Filed: |
April 09, 1996 |
PCT No.: |
PCT/US96/04935 |
371(c)(1),(2),(4) Date: |
March 17, 1998 |
PCT
Pub. No.: |
WO96/33378 |
PCT
Pub. Date: |
October 24, 1996 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
08973090 |
Mar 17, 1998 |
06018954 |
Feb 1, 2000 |
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Foreign Application Priority Data
Current U.S.
Class: |
62/94; 62/271;
62/305; 62/310; 62/332 |
Current CPC
Class: |
F24F
3/1411 (20130101); F24F 3/1417 (20130101); F24F
5/0014 (20130101); F25B 30/02 (20130101); F24F
2003/144 (20130101); F24F 2003/1458 (20130101) |
Current International
Class: |
F25D
17/06 (20060101) |
Field of
Search: |
;62/94,332,271,305,310,93,335 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Doerrler; William C.
Claims
I claim:
1. A heat pump system comprising: two, substantially similar units
in fluid communication with each other, each unit including a
housing, a forced-air counter-flow air/brine heat exchanger, a
brine/refrigerant heat exchanger, brine inlet means for applying
brine onto at least one of said heat exchangers, a brine reservoir
and means for circulating said brine from the reservoir to said
inlet means, said brine/refrigerant heat exchangers being in closed
loop fluid communication with each other and having compressor
means for circulating a refrigerant therethrough in a selected
direction, and for reversing the sense of circulation of the
refrigerant inside said closed loop.
2. A heat pump system, comprising: two, substantially similar units
in fluid communication with each other, each unit including a
housing, brine inlet means at the top portion thereof, a first
air/brine heat exchanger located adjacent said brine inlet means, a
brine reservoir at the lower part of said housing and means for
introducing forced air into brine-dripping space delimited between
said first heat exchanger and said reservoir to produce a
counter-flow air/brine heat exchanger, and a second heat exchanger
in liquid communication with said brine inlet means and said
reservoir; the reservoir of each unit being in liquid communication
with each other; said second heat exchangers being in closed loop
fluid communication with each other and having compressor means for
circulating a refrigerant therethrough in a selected direction, and
for reversing the sense of circulation of the refrigerant inside
said closed loop, and means for circulating brine between said
reservoir and said second heat exchanger of each unit.
3. The heat pump system as claimed in claim 1, wherein said brine
inlet means are drip or spray nozzles.
4. The heat pump system as claimed in claim 2, wherein said means
for introducing air is a blower.
5. The heat pump system as claimed in claim 1, wherein said housing
is common to said first and second heat exchangers.
6. The heat pump system as claimed in claim 5, wherein said brine
inlet means is located above said first and second heat
exchangers.
7. The heat pump system as claimed in claim 2, wherein said first
heat exchanger is an air/brine heat exchanger.
8. The heat pump system as claimed in claim 1, further comprising a
third heat exchanger affixed on brine circulating pipes,
interconnecting said reservoirs.
9. The heat pump system as claimed in claim 8, wherein at least
said unit and said second and third heat exchangers are made of
materials non-corrosive to brine.
10. The heat pump system as claimed in claim 1, further comprising
a throttle valve affixed on a refrigerant carrying pipe
interconnecting said second heat exchangers.
11. The heat pump system as claimed in claim 1, wherein at least
one of said reservoirs is further provided with water inlet means
for adding water to the brine.
12. A heat pump system, comprising: two substantially similar or
identical units in fluid communication with each other, each unit
including a housing, an air/brine heat exchanger, a brine
refrigerant heat exchanger, brine inlet means for applying brine
into at least one of said heat exchangers, a brine reservoir and
means for circulating said brine from the reservoir to said inlet
means, said brine/refrigerant heat exchangers being in closed loop
fluid communication with each other and having compressor means for
circulating a refrigerant therethrough in a selected direction, and
for reversing the sense of circulation of the refrigerant inside
said close loop, and ambient air heating means for heating the
ambient air prior to the introduction thereof into said
housing.
13. The heat pump system as claimed in claim 12, wherein said
heating means is a water/air heat exchanger.
14. A heat pump system, comprising: two substantially similar or
identical units in fluid communication with each other, each unit
including a housing, an air/brine heat exchanger, a brine
refrigerant heat exchanger, brine inlet means for applying brine
into at least one of said heat exchangers, a brine reservoir and
means for circulating said brine from the reservoir to said inlet
means, said brine/refrigerant heat exchangers being in closed loop
fluid communication with each other and having compressor means for
circulating a refrigerant therethrough in a selected direction, and
for reversing the sense of circulation of the refrigerant inside
said closed loop, and an external humidity source for adding
humidity to ambient air introducible into said housing.
15. The heat pump system as claimed in claim 14, wherein said
humidity source is a plant.
16. A method of air conditioning, comprising: providing a heat pump
system as claimed in claim 1, wherein the refrigerant's evaporator
and the refrigerant's condenser exchange heat with brine solution,
whereby the temperature of condensation of said refrigerant is
reduced while the temperature of said evaporator is raised, thereby
increasing the efficiency of the system.
17. The method as claimed in claim 16, wherein said first heat
exchanger is thermally associated with said refrigerant's
evaporator.
18. The method as claimed in claim 16, wherein said first heat
exchanger is thermally associated with said refrigerant's
condenser.
19. A method for air conditioning, comprising: providing a heat
pump system having two substantially similar or identical units in
fluid communication with each other, each unit including a housing,
an air/brine heat exchanger, a brine refrigerant heat exchanger,
brine inlet means for applying brine into at least one of said heat
exchangers, a brine reservoir and means for circulating said brine
from the reservoir to said inlet means, said brine/refrigerant heat
exchangers being in closed loop fluid communication with each other
and having compressor means for circulating a refrigerant
therethrough in a selected direction, and for reversing the sense
of circulation of the refrigerant inside said closed loop, wherein
the refrigerant's evaporator and the refrigerant's condenser
exchange heat with brine solution, whereby the temperature of
condensation of said refrigerant is reduced while the temperature
of said evaporator is raised, thereby increasing the efficiency of
the system, and wherein said means for circulating the brine is
adapted to circulate brine at a higher rate than the rate of
circulation of the brine between said two reservoirs.
20. The heat pump as claimed in claim 1, further comprising means
for circulating brine between said reservoirs.
21. A heat pump, comprising: two substantially similar or identical
units in fluid communication with each other, each unit including a
housing, an air/brine heat exchanger, a brine refrigerant heat
exchanger, brine inlet means for applying brine into at least one
of said heat exchangers, a brine reservoir and means for
circulating said brine from the reservoir to said inlet means; said
brine/refrigerant heat exchangers being in closed loop fluid
communication with each other and having compressor means for
circulating a refrigerant therethrough in a selected direction and
for reversing the sense of circulation of the refrigerant inside
said closed loop; and means for circulating brine between said
reservoirs adapted to circulate brine at a lower rate than the rate
of circulation of brine between the reservoirs and said inlet
means.
22. The heat pump as claimed in claim 20, wherein said means for
circulating brine between said reservoirs are adapted to circulate
brine at a lower rate than the rate of circulation of brine between
the reservoirs and the second heat exchanger of each unit.
23. A heat pump system, comprising: two substantially similar units
in fluid communication with each other, each unit including a
housing, brine inlet means at the top portion thereof, a first heat
exchanger located adjacent said brine inlet means, a brine
reservoir at the lower part of said housing and means for
introducing air into brine-dripping space delimited between said
first heat exchanger and said reservoir, and a second heat
exchanger in liquid communication with said brine inlet means and
said reservoir; the reservoirs of said units being in liquid
communication with each other; said second heat exchangers being in
closed loop fluid communication with each other and having
compressor means for circulating a refrigerant therethrough in a
selected direction and for reversing the sense of circulation of
the refrigerant inside said closed loop; means for circulating
brine between said reservoir and said second heat exchanger of each
unit, and ambient air heating means for heating the ambient air
prior to the introduction thereof into said housing.
24. The heat pump system as claimed in claim 23, wherein said
heating means is a water/air heat exchanger.
25. A heat pump system, comprising: two substantially similar units
in fluid communication with each other, each unit including a
housing, brine inlet means at the top portion thereof, a first heat
exchanger located adjacent said brine inlet means, a brine
reservoir at the lower part of said housing and means for
introducing air into brine-dripping space delimited between said
first heat exchanger and said reservoir, and a second heat
exchanger in liquid communication with said brine inlet means and
said reservoir; the reservoirs of said units being in liquid
communication with each other; said second heat exchangers being in
closed loop fluid communication with each other and having
compressor means for circulating a refrigerant therethrough in a
selected direction and for reversing the sense of circulation of
the refrigerant inside said closed loop; means for circulating
brine between said reservoir and said second heat exchanger of each
unit, and an external humidity source for adding humidity to
ambient air introducible into said housing.
26. The heat pump system as claimed in claim 25, wherein said
humidity source is a plant.
27. A method for air conditioning, comprising: providing a heat
pump system having two substantially similar units in fluid
communication with each other, each unit including a housing, brine
inlet means at the top portion thereof, a first heat exchanger
located adjacent said brine inlet means, a brine reservoir at the
lower part of said housing and means for introducing air into
brine-dripping space delimited between said first heat exchanger
and said reservoir, and a second heat exchanger in liquid
communication with said brine inlet means and said reservoir; the
reservoirs of said units being in liquid communication with each
other; said second heat exchangers being in closed loop fluid
communication with each other and having compressor means for
circulating a refrigerant therethrough in a selected direction and
for reversing the sense of circulation of the refrigerant inside
said closed loop; means for circulating brine between said
reservoir and said second heat exchanger of each unit; wherein the
refrigerant's evaporator and the refrigerant's condenser exchanger
heat with brine solution, whereby the temperature of condensation
of said refrigerant is reduced while the temperature of said
evaporator is raised, thereby increasing the efficiency of the
system, and wherein said means for circulating the brine is adapted
to circulate brine at a higher rate than the rate of circulation of
the brine between said two reservoirs.
28. A heat pump system, comprising: two substantially similar units
in fluid communication with each other, each unit including a
housing, brine inlet means at the top portion thereof, a first heat
exchanger located adjacent said brine inlet means, a brine
reservoir at the lower part of said housing and means for
introducing air into brine-dripping space delimited between said
first heat exchanger and said reservoir, and a second heat
exchanger in liquid communication with said brine inlet means and
said reservoir; the reservoirs of said units being in liquid
communication with each other; said second heat exchangers being in
closed loop fluid communication with each other and having
compressor means for circulating a refrigerant therethrough in a
selected direction and for reversing the sense of circulation of
the refrigerant inside said closed loop, and means for circulating
brine between said reservoir and said second heat exchanger of each
unit, wherein said means for circulating brine are adapted to
circulate brine at a lower rate than the rate of circulation of
brine between the reservoirs and the second heat exchanger of each
unit.
.Iadd.29. A heat pump system, comprising: two units in fluid
communication with each other, each unit including: a housing, an
air/brine heat exchanger, a brine/refrigerant heat exchanger, brine
inlet means for applying brine onto at least one of said heat
exchangers, a brine reservoir and means for circulating said brine
from the reservoir to said inlet means; said brine/refrigerant heat
exchangers of said units being in closed loop fluid communication
with each other and having compressor means for circulating a
refrigerant therethrough in selected directions, and means for
circulating brine between said reservoirs, wherein said means for
circulating the brine between said reservoirs are adapted to
circulate brine at a lower rate than the rate of circulation of the
brine between said reservoirs and said brine inlet
means..Iaddend.
.Iadd.30. A heat pump system, comprising: two units in fluid
communication with each other, each unit including: a housing,
brine inlet means at the top portion thereof, a first heat
exchanger located adjacent said brine inlet means, a brine
reservoir at the lower part of said housing, and means for
introducing air into brine-dripping space delimited between said
first heat exchanger and said reservoir, and a second heat
exchanger in liquid communication with said brine inlet means and
said reservoir; said second heat exchangers being in closed loop
fluid communication with each other and having compressor means for
circulating a refrigerant therethrough in selected directions, and
means for circulating brine between said reservoir and said second
heat exchanger of each unit, and means for circulating brine
between said reservoirs, wherein said means for circulating the
brine between said reservoirs are adapted to circulate brine at a
lower rate than the rate of circulation of the brine between said
reservoirs and said second heat exchanger of each unit.
.Iaddend.
.Iadd.31. The heat pump system as claimed in claim 29, wherein the
reservoirs of each unit are in liquid communication with each
other..Iaddend.
.Iadd.32. The heat pump system as claimed in claim 30, further
comprising a third heat exchanger affixed on brine circulating
pipes, interconnecting said reservoirs..Iaddend.
.Iadd.33. The heat pump system as claimed in claim 32, wherein at
least said unit and said second and third heat exchangers are made
of materials non-corrosive to brine..Iaddend.
.Iadd.34. The heat pump system as claimed in claim 30, further
comprising a throttle valve affixed to a refrigerant-carrying pipe
interconnecting said second heat exchangers..Iaddend.
.Iadd.35. The heat pump system as claimed in claim 29, wherein at
least one of said reservoirs is further provided with water inlet
means for adding water to the brine..Iaddend.
.Iadd.36. The heat pump system as claimed in claim 29, further
comprising ambient air heating means for heating the ambient air
prior to the introduction thereof into said housing..Iaddend.
.Iadd.37. The heat pump system as claimed in claim 36, wherein said
heating means is a water/air heat exchanger..Iaddend.
.Iadd.38. The heat pump system as claimed in claim 29, further
comprising an external humidity source for adding humidity to
ambient air introducible into said housing..Iaddend.
.Iadd.39. The heat pump system as claimed in claim 38, wherein said
humidity source is a plant..Iaddend.
.Iadd.40. A method for air conditioning, comprising: providing a
heat pump system as claimed in claim 29 and further including a
refrigerant evaporator and a refrigerant condenser, wherein the
refrigerant evaporator and the refrigerant condenser exchange heat
with brine solution, whereby the temperature of condensation of
said refrigerant is reduced while the temperature of said
evaporator is raised, thereby increasing the efficiency of the
system..Iaddend.
.Iadd.41. The method as claimed in claim 40, wherein said air/brine
heat exchanger is thermally associated with said refrigerant
evaporator..Iaddend.
.Iadd.42. The method as claimed in claim 40, wherein said air/brine
heat exchanger is thermally associated with said refrigerant
condenser..Iaddend.
.Iadd.43. A dehumidifier system comprising: a dehumidifying chamber
into which moist air is introduced and from which less moist air is
removed after dehumidification; a desiccant solution situated in
two reservoirs; a first conduit via which desiccant solution is
transferred from a first reservoir of said two reservoirs to the
dehumidifying chamber, said solution being returned to said first
reservoir after absorbing moisture from the moist air; a
regenerator which receives desiccant solution from a second
reservoir of said two reservoirs and removes moisture from it; a
second conduit via which desiccant is transferred from said second
reservoir to the regenerator, said solution being returned to said
second reservoir after moisture is removed from it; a heat pump
that transfers heat from the solution in the first conduit to the
solution in the second conduit, and means for circulating desiccant
solution between said reservoirs, wherein said means for
circulating the desiccant between said reservoirs are adapted to
circulate desiccant at a lower rate than the rate of transfer of
said desiccant from said reservoirs to at least one of said
dehumidifying chamber and said regenerator..Iaddend.
.Iadd.44. A dehumidifier system comprising: a dehumidifying chamber
into which moist air is introduced and from which less moist air is
removed after dehumidification; a desiccant solution situated in a
first reservoir; a first conduit via which desiccant solution is
transferred from the first reservoir to the dehumidifying chamber,
said solution being returned to said first reservoir after
absorbing moisture from the moist air; a desiccant solution
situated in a second reservoir; a regenerator which receives
desiccant solution from the second reservoir and removes moisture
from it; a second conduit via which desiccant is transferred from
the second reservoir to the regenerator, said solution being
returned to said second reservoir after moisture is removed from
it; and means for circulating desiccant solution between said
reservoirs, wherein a substantial temperature differential is
maintained between the first and second reservoirs, and wherein
said means for circulating the desiccant between said reservoirs
are adapted to circulate desiccant at a lower rate than the rate of
circulation of the desiccant between said reservoirs and at least
one of said dehumidifying chamber and said
regenerator..Iaddend.
.Iadd.45. A method for air conditioning, comprising: providing a
heat pump system as claimed in claim 30 and further including a
refrigerant evaporator and a refrigerant condenser, wherein the
refrigerant evaporator and the refrigerant condenser exchange heat
with brine solution, whereby the temperature of condensation of
said refrigerant is reduced while the temperature of said
evaporator is raised, thereby increasing the efficiency of the
system..Iaddend.
.Iadd.46. The method as claimed in claim 45, wherein said first
heat exchanger is thermally associated with said refrigerant
evaporator..Iaddend.
.Iadd.47. The method as claimed in claim 45, wherein said first
heat exchanger is thermally associated with said refrigerant
condenser..Iaddend.
Description
The present invention relates to heat pump systems and in
particular to heat pump systems utilizing two subcycles, the first
involving brine and the second a common refrigerant. The invention
also relates to a method of air conditioning, utilizing the heat
pump systems.
Space heating and cooling installations are known. Essentially,
such installations comprise a closed top refrigerant circulated by
means of a compressor through finned pipes located inside a house
and outside thereof. In winter, the compressor forces compressed
and warmed refrigerant into finned pipe sections within the house
where condensation takes place. The liberated heat is usually
dispensed into the house by means of a fan. The condensed
refrigerant then passes through a throttle valve to an evaporator.
The heat of evaporation is provided by the colder outside air.
During summer, the sense of circulation of the refrigerant is
reversed. The outside finned pipes constitute the condenser, while
the inside finned pipes operate as the evaporator.
When such installations are used in areas where the climate is not
mild, however, i.e., where the outside air temperature drops to
close to the freezing mark or even therebelow, ice can accumulate
on the surfaces of the outdoor evaporator and obstruct the air
flow.
It is therefore a broad object of the present invention to
ameliorate the above problem and to provide a heat pump system
adapted to operate efficiently also in more severe climatic
conditions.
It is a further object of the present invention to provide a heat
pump system utilizing brine in heat exchange relationship with a
refrigerant.
In accordance with the present invention there is therefore
provided a heat pump system, comprising two, at least similar units
in fluid communication with each other, each unit including a
housing, a first air/brine heat exchanger, a second
brine/refrigerant heat exchanger, brine inlet means for applying
brine onto at least one of said heat exchangers, a brine reservoir
and means for circulating said brine from the reservoir to said
inlet means, said first and second heat exchangers being in closed
loop fluid communication with each other and having compressor
means for circulating a refrigerant therethrough in selected
directions.
The invention further provides a method for air conditioning,
comprising providing a housing, a first air/brine heat exchanger, a
second brine/refrigerant heat exchanger, brine inlet means for
applying brine onto at least one of said heat exchangers, a brine
reservoir and means for circulating said brine from the reservoir
to said inlet means, said first and second heat exchangers being in
closed loop fluid communication with each other and having
compressor means for circulating a refrigerant therethrough in
selected directions, wherein the refrigerant's evaporator and the
refrigerant's condenser exchange heat with brine solution, whereby
the temperature of condensation of said refrigerant is reduced
while the temperature of said evaporator is raised, thereby
increasing the efficiency of the system.
Hygroscopic brine such as LiBr, MgCl.sub.2, Ca.sub.2cl and mixtures
thereof, can be advantageously used. The concentrations of these
brines will be such that no precipitation of salts or ice
throughout the working range of temperatures of the heat pump will
be formed.
The invention will now be described in connection with certain
preferred embodiments with reference to the following illustrative
figures so that it may be more fully understood.
With specific reference now to the figures in detail, it is
stressed that the particulars shown are by way of example and for
purposes of illustrative discussion of the preferred embodiments of
the present invention only and are presented in the cause of
providing what is believed to be the most useful and readily
understood description of the principles and conceptual aspects of
the invention. In this regard, no attempt is made to show
structural details of the invention in more detail than is
necessary for a fundamental understanding of the invention, the
description taken with the drawings making apparent to those
skilled in the art how the several forms of the invention may be
embodied in practice.
IN THE DRAWINGS
FIG. 1 is a schematic illustration of a heat pump system according
to the present invention;
FIG. 2 is a schematic illustration of another embodiment of a heat
pump according to the present invention, and
FIG. 3 is a modification of the heat pump of FIG. 1.
Seen in the Figure is a heat pump system 2 essentially comprising
two substantially similar units 4 and 6, each acting in its turn as
an evaporator and a condenser, one located inside an enclosure (not
seen) to be air conditioned and the other, outside the enclosure
exposed to ambient air. Each unit respectively includes a housing
8,8' and brine inlet means 10,10' disposed in the upper portion of
the housing. The liquid inlet means is advantageously embodied by a
set of drip or spray nozzles or apertures. Below the brine inlet
means 10,10' there is affixed a brine/air heat exchanger 12,12'.
The latter can be made of densely folded carton paper or of packed
particles, e.g., glass or ceramic, pebbles of beads. The lower
portion of the housing constitutes a brine reservoir 14,14' while
the space 16,16' inside the housing delimited by the liquid level
18,18' and the heat exchanger 12,12', respectively, acts as a brine
dripping space exposed to ambient air introduced thereinto, for
example, by a blower 20,20' or by any other natural or forced
means. Each of the brine inlet means 10,10' is respectively
connected via conduit 22,22' to a second heat exchanger 24,24'. A
conduit 26,26' leads from the heat exchanger 24,24' to the brine
reservoir 14,14' via a circulation pump 28,28', respectively. The
reservoirs 14,14' are in liquid communication via conduits 30 and
32 and advantageously, pass through a third heat exchange 34.
The heat exchangers 24,24', in their simple embodiment are composed
of a closed vessel 36,36' each housing a coil 38,38', respectively.
The coils 38,38' are interconnected, in a closed loop, by pipes
40,42. A compressor 44 fitted on the pipe 40 forces a refrigerant
through the coils 38,38' via a throttle valve 46.
If not all, at least most, of the system's parts and components
should be made of materials non-corrosive to brine.
In order to avoid the necessity of providing synchronization and
control between the pumps 28,28', it is proposed to build the
system such that the brine accumulated in the reservoir 14' will
return to the reservoir 14 through conduit 32 as gravity flow. This
is achieved by locating the reservoir 14' at a higher level than
the level of reservoir 14 or at least inter-connecting the
reservoir's conduit 32 in such orientation so as to slope from
reservoir 14' to reservoir 14. In any case, the brine exchange flow
rate between the reservoirs 14,14' via pipes 30,32 should be
smaller than the circulation rate of the brine in the units 4 or 6
themselves. For operation under certain conditions, it is also
possible to stop the circulation of the brine between the two
units, if desired.
The size of the reservoirs will determine the capacity thereof
acting as heat accumulators for eventual utilization.
Turning to FIG. 2, there is shown another embodiment of the
invention in which the housing 50,50' also encloses the refrigerant
coils 52,52' and the brine inlet means 54,54'. The latter are
located above the coils 52,52', so as to drip or spray brine on the
coils.
The embodiments of FIGS. 1 and 2 can be furnished with an inlet
port 56 for introducing water to the brine reservoirs 14,14'. This
will enable the dilution of the brine when operating the system in
very dry and hot climate, to further increase the efficiency
thereof.
A modification of the system is illustrated in FIG. 3. Here, the
system (of FIG. 1) is further provided with an external source of
humidity in the form of plants 58, in order to increase the
efficiency of the heat pump during the summer time. During the
winter time, however, in order to increase the efficiency, it is
recommended to elevate the temperature of the brine. This can be
achieved by condensing the humidity of the brine by means of hot
air blown by the blower 20. A source of such hot air can be
provided in the form of a hot water to air heat exchanger 60,
having a hot water inlet 62 leading to a drip or spray head 64, a
heat exchange media 66 and a water outlet 68. The cold ambient air
otherwise directly blown into the space 16 will thus be heated
first and only thereafter introduced into the space 16.
As can now be readily understood, the outside or room air
introduced by blowers 20,21' into the housings 8,8', flows as
counter current or cross current to the droplets of brine dripping
in the space 16,16', so as to exchange heat and vapor with the
brine. Since the brine maintains the unit acting as an condenser at
a temperature which is lower than the normal temperature, e.g., at
37.degree. C. instead of 47.degree. C., and parallely, maintains
the evaporator's temperature higher than the normal temperature,
e.g., 4.degree. C. instead of 0.degree. C., it can be shown that
the efficiency of the cycle will be superior at a ratio, of about,
e.g.: .times. ##EQU00001## Hence, the coefficient of performance of
the brine heat pump, according to the present invention as compared
with conventional heat pumps, is substantially higher. In other
words, for the same input of energy, the brine heat pump will
remove 40% more heat from an enclosure in which it is installed as
compared with conventional heat pumps, provided that the mechanical
efficiency of the two compressors is the same.
The average temperature head between the fluid inside and the brine
in the above example is 6.degree. C., and it is anticipated that
for an area of 1 square meter of heat exchanger, the heat transfer
rate will be about 6 Kw.
Therefore, the heat exchange area between the brine and the working
fluid (in heat exchangers 24 and 24') will be small compared with
the area required to transfer heat from the working fluid to the
air in conventional heat pumps.
The small area of the heat exchanger is related to the large heat
conductivity between the condenser and the evaporator's walls
(h=1000 W/Square M..degree. C.) and the brine. The air conductivity
is characterized by 70 watt units only (Watts/(square m C.).
The invention is also usable for refrigeration purposes.
It will be evident to those skilled in the art that the invention
is not limited to the details of the foregoing illustrated
embodiments and that the present invention may be embodied in other
specific forms without departing from the spirit or essential
attributes thereof. The present embodiments are therefore to be
considered in all respects as illustrative and not restrictive, the
scope of the invention being indicated by the appended claims
rather than by the foregoing description, and all changes which
come within the meaning and range of equivalency of the claims are
therefore intended to be embraced therein.
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