Testing system for single heat exchanger of automobile air conditioner with small-filling-amount R290 refrigerant

Abstract

The invention discloses a small-filling-amount R290 refrigerant automobile air conditioner monomer heat exchanger test system which comprises a superheater arranged at an outlet of a compressor, and an outlet of the superheater is connected with a condenser; the first temperature and pressure sensor is arranged at an inlet of the tested condenser; the second temperature and pressure sensor is arranged at an outlet of the tested condenser; the condenser is a test piece or a matching piece; the flowmeter is arranged at the outlet of the condenser, and the outlet is connected with the subcooler; the subcooler is arranged at the inlet of the expansion valve and used for controlling the temperature of the inlet of the expansion valve during evaporator testing; the expansion valve is arranged at an outlet of the subcooler; the third temperature and pressure sensor is arranged at an inlet of the expansion valve; the evaporator is arranged at an outlet of the expansion valve and is a test piece or a matching piece; the fourth temperature and pressure sensor is arranged at an outlet of the evaporator; the liquid storage tank is arranged on a connecting pipeline between the outlet of the flowmeter and the inlet of the compressor; the recovery electromagnetic valve is arranged at an inlet of the liquid storage tank; the filling electromagnetic valve is arranged at an outlet of the liquid storage tank.

Description

Technical Field

[0001] The present invention relates to the field of environmental control, in particular to a test system for a single heat exchanger of an automobile air conditioner with a small filling amount of R290 refrigerant. Background Art

[0002] In the automotive air conditioning sector, as the world accelerates its low-carbon transition, R290 (propane), a natural hydrocarbon refrigerant, offers significant potential for use in closed air conditioning systems, such as electric vehicles and commercial vehicles, due to its environmental friendliness, high energy efficiency, low cost, and compatibility with existing lubricants. However, due to its flammability and explosiveness, the development and application of R290 in automotive air conditioning systems still face numerous challenges. Specifically, in automotive air conditioning heat exchanger testing systems, larger R290 refrigerant refills increase the risk. Therefore, the design and testing of low-recharge systems will become a new direction for technological research and development.

[0003] At present, the existing flammable and explosive refrigerants (such as R290) small filling amount R290 refrigerant automobile air conditioning single heat exchanger test system structure reference Figure 1 As shown, since the evaporator and condenser of the test itself cannot work at the same time, in order to realize the performance test of the heat exchanger, an auxiliary condenser and a calorimeter are also matched. At the same time, the calorimeter needs to assist expensive devices such as electric heating and pressure vessels to work. Therefore, the existing method has a relatively high one-time investment and use cost; in addition, the complex system structure greatly increases the system pipeline and volume, which leads to a significant increase in the recharge amount of flammable and explosive R290, which sharply increases the test safety risk. Therefore, it is particularly important to design a small-filling-volume R290 refrigerant automobile air-conditioning single heat exchanger test system and experimental method for flammable and explosive refrigerants. Summary of the Invention

[0004] The Summary of the Invention introduces a series of simplified concepts, which are simplifications of existing technologies in the field and are further described in detail in the Detailed Description of the Invention. The Summary of the Invention is not intended to define the key features and essential features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0005] The technical problem to be solved by the present invention is to provide a small-fill R290 refrigerant automobile air-conditioning unit heat exchanger test system for thermal performance testing of small-fill flammable and explosive refrigerants, which can minimize the filling amount of flammable and explosive refrigerants in the test system while reducing costs, and reduce the safety risks of testing flammable and explosive air-conditioning system heat exchangers.

[0006] To solve the above technical problems, the present invention provides a small-fill R290 refrigerant automobile air-conditioning unit heat exchanger testing system, comprising:

[0007] A compressor, which is used to provide power for the circulation of flammable and explosive refrigerants in the test system;

[0008] The superheater is installed at the compressor outlet, and its outlet is connected to the condenser being tested. It is used to control the inlet temperature of the tested condenser during the condenser test;

[0009] The first temperature sensor and the first pressure sensor are arranged at the inlet of the condenser to be measured;

[0010] The second temperature sensor and the second pressure sensor are arranged at the outlet of the condenser to be tested;

[0011] Condenser, which is used as a test piece or a matching piece when testing an evaporator;

[0012] A flow meter is installed at the outlet of the condenser, and its outlet is connected to the subcooler, and is used to measure the refrigerant mass flow rate during the experiment;

[0013] Subcooler, installed at the expansion valve inlet, used to control the expansion valve inlet temperature during evaporator testing;

[0014] The expansion valve is located at the outlet of the subcooler and is used to control the outlet temperature of the evaporator;

[0015] A third temperature sensor and a third pressure sensor are arranged at the inlet of the expansion valve;

[0016] The evaporator is located at the outlet of the expansion valve and is used as a test piece or a matching piece for condenser testing;

[0017] A fourth temperature sensor and a fourth pressure sensor are arranged at the evaporator outlet;

[0018] A liquid storage tank is provided on the connecting pipeline between the flow meter outlet and the compressor inlet, and is used to adjust the refrigerant circulation volume of the test system;

[0019] Recovery solenoid valve, installed at the inlet of the liquid storage tank, used to recover the refrigerant in the test system;

[0020] The filling solenoid valve is set at the outlet of the liquid storage tank and is used to fill the refrigerant in the test system.

[0021] Preferably, the small-fill R290 refrigerant automobile air-conditioning unit heat exchanger test system is further improved, and the compressor is an explosion-proof compressor.

[0022] Preferably, the small-fill R290 refrigerant automobile air-conditioning single heat exchanger test system is further improved, the evaporator is air-cooled or water-cooled, and the condenser is a fin-type heat exchanger or a shell-and-tube heat exchanger.

[0023] Preferably, the small-fill R290 refrigerant automobile air-conditioning single heat exchanger test system is further improved, the condenser refrigerant adopts direct heating or indirect system heating, and the electric heating used for heating has explosion-proof characteristics.

[0024] Preferably, the small-fill R290 refrigerant automobile air-conditioning unit heat exchanger test system is further improved, and when performing the condenser heat exchange experiment, the condenser inlet and outlet enthalpy values ​​are H1=f(T1, P1) and H2=f(T2, P2) respectively;

[0025] When performing the evaporator heat exchange experiment, the enthalpy values ​​at the inlet and outlet of the evaporator are H3 = f(T3, P3) and H4 = f(T4, P4).

[0026] T1 to T4 are temperatures collected by the first to fourth temperature sensors respectively;

[0027] P1 to P4 are pressures collected by the first to fourth pressure sensors respectively.

[0028] Preferably, the small-fill R290 refrigerant automobile air-conditioning monomer heat exchanger test system is further improved, and the refrigerant mass flow MF participating in the circulation during the condenser test is obtained according to the flow meter measurement; the heat exchange amount on the condenser refrigerant side is calculated: Qcond = MF*(H2-H1) / 3.6.

[0029] Preferably, the small-fill R290 refrigerant automobile air-conditioning single heat exchanger test system is further improved, and the refrigerant mass flow MF participating in the circulation during the condenser test is obtained according to the flow meter measurement; the heat exchange amount on the evaporator refrigerant side is calculated: Qevap = MF*(H4-H3) / 3.6.

[0030] Compared with the prior art which adopts a flammable and explosive refrigerant replacement system (filling amount is about 5-8 kg), the present invention adopts a full-system flammable and explosive refrigerant monomer test experimental method (filling amount is about 1-1.5 kg), which greatly simplifies the system structure (at least simplifies the calorimeter, system condenser and related pipelines). After the pipeline is simplified, the required refrigerant amount can be reduced. Therefore, the present invention can reduce the refrigerant filling amount in the system, which not only reduces the hardware cost, reduces the complexity of the test system, and reduces the loss of refrigerant, but also the low filling amount test scheme greatly improves the test safety of flammable and explosive refrigerants, and can more safely carry out the heat exchange performance test of the evaporator and condenser of the automobile flammable and explosive refrigerant air-conditioning system while reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The drawings herein are intended to illustrate the general characteristics of methods, structures, and / or materials used in certain exemplary embodiments of the present invention, supplementing the descriptions in the specification. However, the drawings herein are schematic diagrams not drawn to scale and may not accurately reflect the precise structure or performance characteristics of any given embodiment. The drawings herein should not be interpreted as defining or limiting the range of values ​​or properties encompassed by the exemplary embodiments of the present invention. The present invention is further described in detail below in conjunction with the drawings and specific embodiments:

[0032] Figure 1 This is a schematic diagram of the existing R290 refrigerant automobile air conditioner single heat exchanger test system;

[0033] Figure 2 Schematic diagram of a test system for a single heat exchanger in an automobile air conditioner with a small charge of R290 refrigerant provided by the present invention; DETAILED DESCRIPTION

[0034] The following describes the embodiments of the present invention through specific embodiments. Those skilled in the art can fully understand the other advantages and technical effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through different specific embodiments, and the details in this specification can also be applied based on different viewpoints, and various modifications or changes can be made without departing from the overall design concept of the invention. It should be noted that, in the absence of conflict, the following embodiments and the features therein can be combined with each other. The following exemplary embodiments of the present invention can be implemented in a variety of different forms and should not be interpreted as being limited to the specific embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of the present invention thorough and complete, and to fully convey the technical solutions of these exemplary embodiments to those skilled in the art. It should be understood that when an element is referred to as being "connected" or "coupled" to another element, the element can be directly connected or coupled to the other element, or there can be an intermediate element. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there is no intermediate element. In all figures, the same figure numbers always represent the same elements.

[0035] First embodiment;

[0036] refer to Figure 2 As shown, the present invention provides a small-fill R290 refrigerant automobile air-conditioning unit heat exchanger test system, comprising:

[0037] A compressor, which is used to provide power for the circulation of flammable and explosive refrigerants in the test system;

[0038] The superheater is installed at the compressor outlet, and its outlet is connected to the condenser being tested. It is used to control the inlet temperature of the tested condenser during the condenser test;

[0039] The first temperature sensor and the first pressure sensor are arranged at the inlet of the condenser to be measured;

[0040] The second temperature sensor and the second pressure sensor are arranged at the outlet of the condenser to be tested;

[0041] Condenser, which is used as a test piece or a matching piece when testing an evaporator;

[0042] A flow meter is installed at the outlet of the condenser, and its outlet is connected to the subcooler, and is used to measure the refrigerant mass flow rate during the experiment;

[0043] Subcooler, installed at the expansion valve inlet, used to control the expansion valve inlet temperature during evaporator testing;

[0044] The expansion valve is located at the outlet of the subcooler and is used to control the outlet temperature of the evaporator;

[0045] A third temperature sensor and a third pressure sensor are arranged at the inlet of the expansion valve;

[0046] The evaporator is located at the outlet of the expansion valve and is used as a test piece or a matching piece for condenser testing;

[0047] A fourth temperature sensor and a fourth pressure sensor are arranged at the evaporator outlet;

[0048] A liquid storage tank is provided on the connecting pipeline between the flow meter outlet and the compressor inlet, and is used to adjust the refrigerant circulation volume of the test system;

[0049] The recovery solenoid valve is installed at the inlet of the liquid storage tank and is used to recover the refrigerant in the test system. During the recovery, the condenser outlet temperature drops and rises;

[0050] The filling solenoid valve is set at the outlet of the liquid storage tank and is used to fill the refrigerant in the test system. During filling, the condenser outlet temperature drops.

[0051] Among them, the compressor is an explosion-proof compressor, the evaporator is air-cooled or water-cooled, the condenser is a fin-type heat exchanger or a shell-and-tube heat exchanger, the condenser refrigerant adopts direct heating or indirect system heating, and the electric heating used for heating has explosion-proof characteristics.

[0052] Based on the structure of the test system for a single heat exchanger of an automobile air conditioner with a small amount of R290 refrigerant provided in the first embodiment;

[0053] When performing the condenser heat exchange experiment, the enthalpy values ​​at the inlet and outlet of the condenser are H1 = f(T1, P1) and H2 = f(T2, P2).

[0054] When performing the evaporator heat exchange experiment, the enthalpy values ​​at the inlet and outlet of the evaporator are H3 = f(T3, P3) and H4 = f(T4, P4).

[0055] T1 to T4 are temperatures collected by the first to fourth temperature sensors respectively;

[0056] P1 to P4 are pressures collected by the first to fourth pressure sensors respectively.

[0057] Therefore, according to the liquid flow meter method and enthalpy difference method of heat exchanger testing, the heat transfer capacity of the condenser refrigerant side can be obtained: Qcond = MF*(H2-H1) / 3.6;

[0058] Therefore, according to the liquid flow meter method and enthalpy difference method of heat exchanger testing, the heat transfer capacity of the refrigerant side of the evaporator can be obtained: Qevap = MF*(H4-H3) / 3.6;

[0059] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will also be understood that, unless expressly defined herein, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, rather than being interpreted in an idealized or overly formal sense.

[0060] The present invention has been described in detail above by way of specific embodiments and examples, but these do not constitute limitations of the present invention. Without departing from the principles of the present invention, those skilled in the art may make many variations and improvements, which should also be considered within the scope of protection of the present invention.

Claims

1. A small-fill R290 refrigerant automobile air-conditioning unit heat exchanger test system, characterized in that: include: A compressor, which is used to provide power for the circulation of flammable and explosive refrigerants in the test system; The superheater is installed at the compressor outlet, and its outlet is connected to the condenser being tested. It is used to control the inlet temperature of the tested condenser during the condenser test; The first temperature sensor and the first pressure sensor are arranged at the inlet of the condenser to be measured; The second temperature sensor and the second pressure sensor are arranged at the outlet of the condenser to be tested; Condenser, which is used as a test piece or a matching piece when testing an evaporator; A flow meter is installed at the outlet of the condenser, and its outlet is connected to the subcooler, and is used to measure the refrigerant mass flow rate during the experiment; Subcooler, installed at the expansion valve inlet, used to control the expansion valve inlet temperature during evaporator testing; The expansion valve is located at the outlet of the subcooler and is used to control the outlet temperature of the evaporator; A third temperature sensor and a third pressure sensor are arranged at the inlet of the expansion valve; The evaporator is located at the outlet of the expansion valve and is used as a test piece or a matching piece for condenser testing; A fourth temperature sensor and a fourth pressure sensor are arranged at the evaporator outlet; A liquid storage tank is provided on the connecting pipeline between the flow meter outlet and the compressor inlet, and is used to adjust the refrigerant circulation volume of the test system; Recovery solenoid valve, installed at the inlet of the liquid storage tank, used to recover the refrigerant in the test system; The filling solenoid valve is set at the outlet of the liquid storage tank and is used to fill the refrigerant in the test system.

2. The small-fill R290 refrigerant automobile air conditioner single heat exchanger test system according to claim 1, characterized in that: The compressor is an explosion-proof compressor.

3. The small-fill R290 refrigerant automobile air conditioner single heat exchanger testing system according to claim 1, characterized in that: The evaporator is air-cooled or water-cooled, and the condenser is a finned heat exchanger or a shell-and-tube heat exchanger.

4. The small-fill R290 refrigerant automobile air conditioner single heat exchanger testing system according to claim 1, characterized in that: The condenser refrigerant adopts direct heating or indirect system heating, and the electric heating used for heating has explosion-proof characteristics.

5. The small-fill R290 refrigerant automobile air conditioner single heat exchanger testing system according to claim 1, characterized in that: When performing the condenser heat exchange experiment, the enthalpy values ​​at the inlet and outlet of the condenser are H1 = f(T1, P1) and H2 = f(T2, P2). When performing the evaporator heat exchange experiment, the enthalpy values ​​at the inlet and outlet of the evaporator are H3 = f(T3, P3) and H4 = f(T4, P4). T1 to T4 are temperatures collected by the first to fourth temperature sensors respectively; P1 to P4 are pressures collected by the first to fourth pressure sensors respectively.

6. The small-fill R290 refrigerant automobile air-conditioning unit heat exchanger test system according to claim 5, characterized in that: The refrigerant mass flow rate MF involved in the circulation during the condenser test is measured using a flow meter; the heat exchange on the refrigerant side of the condenser is calculated as: Qcond = MF*(H2-H1) / 3.

6.

7. The small-fill R290 refrigerant automobile air conditioner unit heat exchanger test system according to claim 5, characterized in that: The refrigerant mass flow rate MF involved in the circulation during the condenser test is measured using a flow meter; the heat exchange on the refrigerant side of the evaporator is calculated as: Qevap = MF*(H4-H3) / 3.6.

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