The present invention relates to a refrigeration or air conditioning technology and, more particularly, to a condenser.
A refrigerator or an air conditioner primarily comprises a compressor, a condenser, an expansion valve, and an evaporator. A refrigerant in turn passes through the compressor, the condenser, the expansion valve, and the evaporator. When a gaseous refrigerant having low pressure and normal temperature is compressed by the compressor, the refrigerant is compressed into a gaseous refrigerant having high pressure and high temperature. When the gaseous refrigerant having high pressure and high temperature is cooled by air or water in the condenser, the refrigerant is condensed into a liquid refrigerant having high pressure and normal temperature. When the liquid refrigerant having high pressure and normal temperature is expanded by the expansion valve, the refrigerant is throttled or expanded into a liquid refrigerant having low pressure and normal temperature. When the liquid refrigerant having low pressure and normal temperature is evaporated by the evaporator, the refrigerant is changed into a gaseous refrigerant having low pressure and normal temperature. Thus, the complete refrigeration or air conditioning cycle is finished.
A conventional condenser 1 in accordance with the prior art shown in
Referring to
In the compressing process a-b of the compressor,
W
c
=G×(hb−ha)
In the condensing process b-c of the condenser,
Q
c
=G×(hb−hc)
In the throttling (or expansion) process c-d of the expansion valve,
hd=hc
In the evaporation process d-a of the evaporator,
Q
e
=G×(ha−hd)
In the operation balance of the compressor,
Q
c
=Q
e
+W
c
wherein,
Wc=power of the compressor, the unit is KJ/S(KW)
G=mass flow rate of the refrigerant, the unit is KG/S
h=enthalpy of the refrigerant, the unit is KJ/KG
Qc=heat output per unit time of the condenser, the unit is KJ/S(KW)
Qe=heat input per unit time of the evaporator, the unit is KJ/S(KW)
The heat transfer equations of the conventional condenser 1 are described as follows.
Q
c
=UA(LMTD)
LMTD=(ΔTA−ΔTB)/ln(ΔTA/ΔTB)
ΔTA=Tc−TA
ΔTB=Tc−TB
wherein,
Qc=heat output per unit time of the condenser, the unit is KJ/S(KW)
U=total heat transfer coefficient, the unit is KW/M2° C.
A=surface area of heat transfer, the unit is M2
LMTD=logarithm mean temperature difference of the condenser, the unit is ° C.
TC=condensing temperature of the refrigerant at the two-phase state, the unit is ° C.
TA=temperature of the cooling fluid at A (or entrance) position, the unit is ° C.
TB=temperature of the cooling fluid at B (or exit) position, the unit is ° C.
ΔTA=TC−TA
ΔTB=TC−TB
It is clear that, the gaseous refrigerant 13 having high pressure and high temperature is introduced from the compressor 12 into the refrigerant inlet port of the gaseous refrigerant section 10. The gaseous refrigerant 13 is transformed into the liquid refrigerant 15 after the heat exchange process. In the conventional condenser 1, the refrigerant space is a balance zone of a liquid phase and a gaseous phase, wherein the liquid refrigerant 15 occupies a large proportion of the refrigerant space. However, the liquid refrigerant 15 is disposed at an almost stagnating state and flows slowly so that the heat conduction effect is poor. Thus, it is necessary to increase the heat conduction area to compensate the poor heat conduction. In addition, the exit temperature (TB) is less than the condensing temperature (TC), that is, ΔTB>0, which indicates that the heat exchange or condensing efficiency is limited.
The primary objective of the present invention is to provide a condenser comprising a gaseous refrigerant section, a liquid refrigerant section, a heat exchange channel, a refrigerant inlet port, and a refrigerant outlet port. The heat exchange channel allows flowing of a cooling fluid. An overheat gaseous refrigerant having high pressure and high temperature is introduced from a compressor into the refrigerant inlet port. A liquid refrigerant is introduced through the refrigerant outlet port into an expansion valve. The refrigerant inlet port is located at the liquid refrigerant section to enhance a working efficiency of the condenser.
In practice, the overheat gaseous refrigerant having high pressure and high temperature is introduced through the refrigerant inlet port into the liquid refrigerant section of the condenser. The overheat gaseous refrigerant and the liquid refrigerant in the condenser produce a stirred fluid to enhance the heat transfer effect so that the temperature of the overheat gaseous refrigerant is reduced, and the overheat gaseous refrigerant is condensed, while the liquid refrigerant in the condenser absorbs heat and is evaporated. Thus, the working efficiency of the condenser is enhanced.
The principle of the present invention is described as follows. The heat conduction feature is affected by three primary factors. The first factor is temperature difference wherein when the temperature difference of the heat exchange fluid is increased, the heat conduction efficiency is increased. The second factor is turbulence wherein when the turbulence of the heat exchange fluid is increased, the heat conduction efficiency is increased. The third factor is time wherein when the heat exchange time of the heat exchange fluid is increased, the heat conduction efficiency is increased.
In practice, the overheat gaseous refrigerant having high pressure and high temperature is introduced through the bottom of the condenser so that the temperature of the liquid refrigerant in the condenser is increased. Thus, the temperature difference of the heat exchange fluid is increased so that the heat conduction efficiency is increased. In addition, the overheat gaseous refrigerant having high pressure and high temperature is introduced through the bottom of the condenser and flows upward due to its buoyancy so that the liquid refrigerant in the condenser produces a turbulence. Thus, the turbulence of the heat exchange fluid is increased so that the heat conduction efficiency is increased. Further, the overheat gaseous refrigerant having high pressure and high temperature is introduced through the bottom of the condenser and flows upward due to its buoyancy so that the overheat gaseous refrigerant has to flow to the top of the condenser and then is condensed and lowered to the refrigerant outlet port. Thus, the moving distance of the overheat gaseous refrigerant in the condenser is increased, and the heat exchange time of the heat exchange fluid is increased, so that the heat conduction efficiency is increased.
In accordance with the present invention, the condenser further comprises an aeration device mounted on the refrigerant inlet port and connected to the overheat gaseous refrigerant. the aeration device increases the contact area of the overheat gaseous refrigerant and the liquid refrigerant to enhance the heat conduction effect.
Preferably, the aeration device is made of porous material.
Preferably, the aeration device is a tube or sheet plate with multiple air apertures.
In accordance with the present invention, the condenser further comprises a partition mounted in the liquid refrigerant section. The partition divides the liquid refrigerant section into a high temperature stirring zone and a low temperature non-stirring zone so that the liquid refrigerant is cooled exactly and then flows out of the condenser.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.
Referring to the drawings and initially to
The primary characteristic of the present invention is in that, the refrigerant inlet port 33 is located at the liquid refrigerant section 31 to enhance a working efficiency of the condenser 3. The overheat gaseous refrigerant 34 having high pressure and high temperature is introduced through the refrigerant inlet port 33 into the liquid refrigerant section 31 of the condenser 3.
In the preferred embodiment of the present invention, the condenser 3 is an air cooled condenser, a water cooled condenser, a manifold condenser, a finned condenser, a shell condenser, or the like.
In the preferred embodiment of the present invention, the refrigerant inlet port 33 is located at a bottom of the condenser 3.
In practice, when the overheat gaseous refrigerant 34 having high pressure and high temperature is introduced through the refrigerant inlet port 33 into the condenser 3, a heat transfer (or heat exchange) is produced between the overheat gaseous refrigerant 34 and the liquid refrigerant (or the cooling fluid 32) so that the overheat gaseous refrigerant 34 having high pressure and high temperature is cooled by the liquid refrigerant (or the cooling fluid 32) and condensed into a liquid refrigerant having high pressure and normal temperature, while the liquid refrigerant (or the cooling fluid 32) absorbs heat and is evaporated. At this time, the overheat gaseous refrigerant 34 having high pressure and high temperature flows upward due to its buoyancy so that the overheat gaseous refrigerant 34 will not be directly drained outward from the refrigerant outlet port 35. Thus, the working efficiency of the condenser 3 is enhanced.
Referring to
Referring to
Referring to
In comparison, the difference between the condenser 3 of the present invention and the conventional condenser 1 of the prior art is in that, the conventional condenser 1 is under a static balance state wherein when the temperature of the liquid-gas balance zone is increased, the pressure is also increased, but the condenser 3 of the present invention is under a liquid-gas balance state with successive perturbation or turbulence. Thus, the heat transfer modes are different so that the heat transfer features are also different.
The heat transfer equation of the condenser 3 of the present invention is Qc′=UA(LMTD), wherein:
Qc′=heat output per unit time of the condenser, the unit is KJ/S(KW)
U=total heat transfer coefficient, the unit is KW/M2° C.
A=surface area of heat transfer, the unit is M2
LMTD=logarithm mean temperature difference of the condenser, the unit is ° C.
The heat transfer mode of the condenser 3 of the present invention is different from that of the conventional condenser 1 and will not be further described in detail.
Referring to
In the preferred embodiment of the present invention, the aeration device 37 is made of porous material.
In the preferred embodiment of the present invention, the aeration device 37 is a tube or sheet plate with multiple air apertures.
Referring to
Although the overheat gaseous refrigerant 34 flows upward by its buoyancy and will not directly flow into the refrigerant outlet port 35, the liquid refrigerant section 31 is divided into the high temperature stirring zone 310 and the low temperature non-stirring zone 311 to assure that the liquid refrigerant is cooled exactly in the low temperature non-stirring zone 311 before flowing out of the condenser 3.