CONDENSER FOR WASTE HEAT UTILIZATION OF AUTOMOBILE AIRCONDITIONING SYSTEM
TECHNICAL FIELD
The subject matter described herein, in general, relates to an automobile air conditioning system and in particular, relates to a condenser for an automobile air conditioning system with improved waste heat utilization.
BACKGROUND
Air conditioning systems are capable of controlling humidity, airflow and temperature of a cabin in a vehicle and thus, increasing passengers’ comfort during the drive of the vehicle. The principle of an air conditioning system is based on the heat exchange process between a refrigerant and the surrounding air which primarily happens in a condenser and an evaporator. The condenser is placed on the front side of the vehicle, exposed to the environment whereas the evaporator is placed in the interior of the vehicle in order to draw heat from the cabin. The air conditioning system further comprises a compressor and an expansion valve. The refrigerant is compressed in the compressor and expanded by the expansion valve to generate lower temperature than the temperature of environment. The refrigerant then flows to the evaporator to absorb heat from the cabin and gets evaporated. A blower is used to generate cooled air flow in the cabin by flowing air on the surface of the cooled coolant pipe. The refrigerant vapor is then routed back to the compressor to repeat the refrigeration cycle. Due to decrease of the air temperature inside the cabin, the atmospheric water vapors condense on the
3
evaporator. This water condensate is stored in the lower portion of the evaporator and then drained to the atmosphere.
Thus, there is a need to increase the efficiency and thermal performance of the air conditioning system of a vehicle.
SUMMARY
It is an object of the present subject matter to improve the performance of an air conditioning system of a vehicle.
It is another object of the present subject matter to provide a condenser assembly of an air conditioning system of a vehicle with increased efficiency.
It is another object of the present subject matter to provide a condenser assembly of an air conditioning system of a vehicle with improved thermal performance.
It is another object of the present subject matter to utilize the water condensate stored in the evaporator.
The present subject matter relates to a condenser assembly for an automobile air conditioning system, the condenser assembly comprising: a receiver drier fluidly connected to a core of the condenser assembly for flow of a refrigerant from the core to the receiver drier and vice versa, the receiver drier utilizing a water condensate from an evaporator assembly for extracting heat from the refrigerant circulating in the receiver drier.
4
In an embodiment of the present subject matter the receiver drier is circumferentially surrounded by a jacket throughout the length of the receiver drier to facilitate flow of the water condensate there through for extracting heat from the refrigerant circulating in the receiver drier.
In another embodiment of the present subject matter, the jacket comprises an inlet for receiving the water condensate from the evaporator assembly and an outlet for releasing the water or atmosphere.
In yet another embodiment of the present subject matter, the inlet is fluidly connected to the evaporator assembly through an inlet pipe.
In yet another embodiment of the present subject matter, the inlet pipe and the outlet pipe are insulated.
In yet another embodiment of the present subject matter, the jacket is of semi-circular shape.
In yet another embodiment of the present subject matter, the jacket is extruded by an extrusion die in molten condition.
In yet another embodiment of the present subject matter, the amount of the water condensate flowing through the jacket by gravity is controlled by a regulating valve.
In yet another embodiment of the present subject matter, the jacket is made of aluminum.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
The foregoing and further objects, features and advantages of the present subject matter will become apparent from the following description of exemplary
5
embodiments with reference to the accompanying drawings, wherein like numerals are used to represent like elements.
It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter, and are therefore, not to be considered for limiting of its scope, for the subject matter may admit to other equally effective embodiments.
Figure 1 illustrates a schematic representation of an air conditioning system 102 of an automobile 100 in accordance with one embodiment of the present subject matter.
Figure 1a illustrates a partial perspective view of a vehicle cabin 104 depicting an expansion valve 124 and an evaporator assembly 126 of the automobile air conditioning system 102 positioned inside a front Heating, ventilation and air conditioning system in accordance with one embodiment of the present subject matter.
Figure 2 illustrates a perspective view of a conventional receiver drier 142 and a receiver drier 118 according to the present subject matter.
Figure 3 illustrates a schematic representation of a condenser assembly 112 in accordance with one embodiment of the present subject matter.
Figure 4 illustrates a sectional view of a receiver drier 118 of the condenser assembly 112 in accordance with one embodiment of the present subject matter.
Figure 5 illustrates a graph depicting dependency of Condenser capacity and drain water flow in a conventional air conditioning system and the air conditioning system of the present subject matter.
DETAILED DESCRIPTION
6
The following presents a detailed description of various embodiments of the present subject matter with reference to the accompanying drawings.
The embodiments of the present subject matter are described in detail with reference to the accompanying drawings. However, the present subject matter is not limited to these embodiments which are only provided to explain more clearly the present subject matter to a person skilled in the art of the present disclosure. In the accompanying drawings, like reference numerals are used to indicate like components.
The subject matter described herein relates to a condenser assembly with waste heat utilization in air-conditioning system of an automobile. Figure 1 illustrates a schematic representation of an air conditioning system 102 of an automobile 100 in accordance with one embodiment of the present subject matter. The automobile 100 comprises an air conditioning system 102 capable of cooling a cabin 104. The cooling of the cabin 104 is facilitated by a heat exchange process between a refrigerant (not shown in the Figure) and the air present inside the cabin 104. The refrigerant circulates in the air conditioning system 102 in gas and liquid phases. When the refrigerant is in a gas phase, the refrigerant enters a compressor 108. The compressor 108 is disposed in the bonnet 110 of the automobile 100 and is driven by an engine of the automobile 100. Upon entering the compressor 108, the refrigerant in the gaseous form is compressed and hence, the pressure and the temperature of the refrigerant is increased. In an embodiment, the temperature of the refrigeration in the compressor is increased up to 87degC. Thereafter, the high-pressure and high-temperature refrigerant gas enters a condenser assembly 112 via an inlet 114. As the refrigerant gas passes through a core 116 of the condenser assembly 112, the refrigerant starts cooling down and condenses into liquid. From the core 116 of the condenser assembly 112, a mixture of liquid and
7
gaseous refrigerant enters a receiver drier 118 connected thereto for separating impurities and particles present in the refrigerant. The process of conversion of the gaseous refrigerant into a liquid refrigerant continues in the receiver drier 118. After passing through the receiver drier 118, the liquid refrigerant returns to the core 116 of the condenser assembly 112 for conversion of the remaining refrigerant in gaseous phase into the liquid phase. The refrigerant in completely liquid phase then flows out of the condenser assembly 112 through an outlet 122 and is diverted to an expansion valve 124 as shown in Figure 1a. After leaving the condenser assembly 112, the temperature of the liquid refrigerant is about 44.85degC. Once the refrigerant liquid passes through the expansion valve 124, the refrigerant liquid gets expanded and the temperature of the refrigerant liquid further decreases. The cold refrigerant liquid then enters an evaporator assembly 126 as shown in Figure 1a to absorb heat from the inside of the cabin 104. As a result of heat transfer from the cabin 104 to the refrigerant inside the evaporator assembly 126, the liquid refrigerant starts evaporating and converting into gas. The gas refrigerant then returns to the compressor 108 to repeat the refrigeration cycle. As can be seen from Figure 1a, the expansion valve 124 and the evaporator assembly 126 are placed inside a front Heating, ventilation and air conditioning (HVAC) system 132.
The exchange of heat from the air inside the cabin 104 to the refrigerant in the evaporator assembly 126, results in cooling of vapors present in the atmosphere along with evaporator. The water condensate is stored in the lower casing of the HVAC system 132. The higher the humidity, more is the amount of water condensed due to heat exchange process in the evaporator assembly 126. Due to the frequent use of the air conditioning system 102 the amount of water condensate stored in the lower casing of the HVAC system 132 increases by about 10% to 15%. However, the average
8
amount of the water condensate stored in the lower casing of the HVAC system132 is about 250ml and the average temperature of the water condensate is about 10-15degC.
According to the present subject matter, the water condensate stored in the lower casing of the HVAC system 132 is utilized by gravity to cool the refrigerant circulating inside the receiver drier 118. This is achieved by providing a jacket 120 around the receiver drier 118 and fluidly connecting the jacket 120 with the lower casing of the HVAC system 132. An insulated inlet pipe 128 is provided to connect the lower casing of the HVAC system 132 with an inlet 130 of the jacket 120 for transporting the water condensate from the lower casing of the HVAC system 132 to the jacket 120. A regulating valve 140 is installed on the inlet pipe 128 to control the flow of the water condensate in the jacket 120. In an embodiment of present subject matter, the regulating valve 140 allows the flow of the water condensate at 10ml/min to 15 ml/min from the lower casing of the HVAC system 132 to the jacket 120. The flow of the water condensate inside the jacket 120 facilitates further cooling of the refrigerant inside the receiver drier 118. In an embodiment of present subject matter, the temperature of the refrigerant is further decreased by about 1-3 degC and the temperature of the water condensate increases by about 17 to 27 degC. Thereafter, the water condensate at higher temperature flows out of the jacket 120 through an outlet 134. The outlet 134 is connected to an outlet pipe 136 for releasing the water condensate at higher temperature to a sump 138 in order to store the water condensate for consequent use in a radiator (not shown in Figure 1). However, in another embodiment, the water condensate at higher temperature exiting the jacket 120 can be released to the atmosphere.
9
Figure 2 illustrates a conventional receiver drier 142 and the receiver drier 118 according to the present subject matter having the circumferentially surrounding jacket 120. In an embodiment of the present subject matter, the jacket 120 has a semi-circular shape and is positioned throughout the length of the receiver drier 118 thereby ensuring that a large surface is utilized for transfer of heat from the refrigerant to the water condensate. However in another embodiment, the length of the jacket 120 may be smaller than the length of the receiver drier 118 as per the requirement. In an embodiment of present subject matter, the jacket 120 is extruded through an extrusion die in molted condition and the width of the extrusion part is about 176mm. Further, the jacket is made of aluminum in accordance with a preferred embodiment of the present subject matter. The refrigerant enters the receiver drier 118 from the core 116 the condenser assembly 112 through an inlet 144 and flows out back to the core 116 via an outlet 146.
Figure 3 illustrates a schematic representation of the condenser assembly 112 having the receiver drier 118 with the circumferential jacket 120 in accordance with a preferred embodiment of the present subject matter. In an embodiment of the present subject matter, the jacket 120 comprises the inlet 130 and the outlet 134 for facilitating the entry of the water condensate into the receiver drier 118 and exit therefrom respectively. In an embodiment, the inlet pipe 128 and the outlet pipe 136 are brazed. In a preferred embodiment, the inlet 130 has a diameter of about 8mm. The inlet pipe 128 in the present embodiment has one inlet 130 and a plurality of outlets (not shown on Figure 3). The first outlet has a diameter of about 6mm and the second outlet has a diameter of about 2.5mm.
10
The pipes 128, 136 for circulation of the water condensate are required to be properly insulated. The water pipe bends need to be optimized to counter the loss of pressure during the flow of the water condensate. The water pipes should be properly tightened and should not have a contact with hot parts of an engine. The height of the water pipes 128, 136 is also required to be kept in a slanting order from the HVAC system 132 to the jacket 120 so that water condensate flows freely by gravity. The pipes for circulation of the water condensate can be made from plastic, synthetic rubber or natural rubber in different embodiments. The water pipes are insulated to stop the heat transfer between the water condensate and the atmosphere.
Figure 4 illustrates a sectional view of the receiver drier 118 having a circumferentially surrounding jacket 120. In the present embodiment of the current subject matter, the dimensions of the receiver drier 118 and the jacket 120 are as follows:
A: 44mm diameter
B: 38mm diameter
C: 1.5mm
D: 2.5mm
E: 35.6mm
F: 28.6mm
G: 1mm radius
H: 30.8mm diameter
I: 10mm radius
J: 14mm
11
In a preferred embodiment of the present subject matter, the weight of the condensate assembly 118 is about 1.45 kg. The weight to performance ratio is higher by 1-1.5% in comparison to the conventional condenser assembly.
Figure 5 illustrates a graph describing dependency of a Condenser Capacity and Evaporator drain water flow in a conventional system and the system according to the present subject matter. In an embodiment of present subject matter, the thermal performance is improved by about 3-5% in comparison to the conventional condensers. As indicated in Figure 5, the condenser capacity can reach up to 9800 Watts having 6kg/hr drain water flow as opposed to conventional condensers in which the maximum condenser capacity is about9482 Watts.
Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore, contemplated that such modifications can be made without departing from the spirit or scope of the present invention as defined.
12
I/WE CLAIM
1. A condenser assembly 112 for an automobile air conditioning system 102, the condenser assembly 112 comprising:
a receiver drier 118 fluidly connected to a core 116 of the condenser assembly 112 for flow of a refrigerant from the core 116 to the receiver drier 118 and vice versa, the receiver drier utilizing a water condensate from an evaporator assembly 126 for extracting heat from the refrigerant circulating in the receiver drier 118.
2. The condenser assembly 112 for an automobile air conditioning system 102 as claimed in claim 1, wherein the receiver drier 118 is circumferentially surrounded by a jacket 120 throughout the length of the receiver drier 118 to facilitate flow of the water condensate there through for extracting heat from the refrigerant circulating in the receiver drier 118.
3. The condenser assembly 112 for an automobile air conditioning system 102 as claimed in claim 1, wherein the jacket 120 comprises an inlet 130 for receiving the water condensate from the evaporator assembly 126 and an outlet 134 for releasing the water condensate to an external circuit.
4. The condensate assembly 112 for an automobile air conditioning system 102 as claimed in claim 3, wherein the inlet 130 is fluidly connected to the evaporator assembly 126 through an inlet pipe 128.
5. The condensate assembly 112 for an automobile air conditioning system 102 as claimed in claim 3, wherein the outlet 134 is fluidly connected to the external circuit through an outlet pipe 136.
13
6. The condensate assembly 112 for an automobile air conditioning system 102 as claimed in claims 4 and 5, wherein the inlet pipe 128 and the outlet pipe 136 are insulated.
7. The condensate assembly 112 for an automobile air conditioning system 102 as claimed in claim 1, wherein the jacket 120 is of a semi-circular shape.
8. The condensate assembly 112 for an automobile air conditioning system 102 as claimed in claim 1, wherein the jacket 120 is extruded by an extrusion die in molten condition.
9. The condensate assembly 112 for an automobile air conditioning system 102 as claimed in claim 1, wherein the amount of the water condensate flowing through the jacket 120 by gravity is controlled by a regulating valve 140.
10. The condensate assembly 112 for an automobile air conditioning system 102 as claimed in claim 1, wherein the jacket s120 is made of aluminum.