System and method for testing gas-liquid separation capacity of gas-liquid separator

Abstract

The invention provides a gas-liquid separation capacity test system of a gas-liquid separator, which comprises a compressor, a condenser, a flow meter, an OCR meter, an EXV electronic expansion valve, a first evaporator, a debugging station connected with a first gas-liquid separator, a test station connected with a second gas-liquid separator, and a debugging loop and a test loop formed by a second evaporator, the debugging loop is further provided with a first adjusting valve, a second adjusting valve, a third temperature pressure sensor and a fourth temperature pressure sensor. The testing loop is further provided with a third adjusting valve, a fourth adjusting valve, a first temperature pressure sensor and a second temperature pressure sensor. The invention further provides a testing method of the gas-liquid separation capacity testing system of the gas-liquid separator, the system is stabilized through the debugging loop, and then the system is switched to the testing loop. According to the gas-liquid separation capacity test system and test method of the gas-liquid separator, the test system is more stable by adding the debugging loop, the operation is simple, and the test precision is high.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive air-conditioning thermal management. Specifically, it relates to a gas-liquid separation capacity testing system and testing method for a gas-liquid separator. Background Art

[0002] The gas-liquid separation capacity of an air-conditioning gas-liquid separator refers to the degree to which it can effectively separate the liquid and gaseous refrigerants in the gas-liquid two-phase refrigerant at the outlet of the evaporator of the air-conditioning system. This is the key to ensuring the stable operation of the air-conditioning system. The level of separation efficiency directly affects the cooling and heating effects and energy consumption of the air-conditioning system. If the separation effect is poor, liquid refrigerant may enter the compressor, resulting in compressor damage or performance degradation.

[0003] The air-conditioning gas-liquid separator separates based on the weight or density difference between the liquid and gas in the refrigerant. When the gas-liquid two-phase refrigerant enters the gas-liquid separator, its kinetic energy is reduced through a specific structure or device, and large-sized liquid droplets entrained in the gas are removed. Subsequently, the gas phase carrying the remaining small-sized liquid droplets enters the high-efficiency separation area, such as separation blades. The trapped liquid is collected below the blades and stored in the cavity of the gas-liquid separator.

[0004] An efficient air-conditioning gas-liquid separator should ensure that the gas inhaled by the compressor is pure, reducing the damage caused by liquid slugging to the compressor. The level of separation efficiency directly affects the cooling effect and energy consumption of the air-conditioning system. If the separation effect is poor, liquid refrigerant may enter the compressor, resulting in compressor damage or performance degradation.

[0005] Therefore, the gas-liquid separation capacity of the gas-liquid separator is an important indicator for evaluating the performance of the gas-liquid separator. However, since the refrigerant at the outlet of the gas-liquid separator is in a two-phase state, the enthalpy value here cannot be directly obtained by measuring pressure and temperature. The testing method required by the national standard needs to use a set of adiabatic heaters with a fixed heating amount to heat the two-phase refrigerant at the outlet of the gas-liquid separator until the two-phase refrigerant is completely evaporated into a gaseous state. The enthalpy value of the heated refrigerant is obtained by looking up a table, and then the dryness value at the outlet of the gas-liquid separator is obtained by looking up a table. The gas-liquid separation capacity of the gas-liquid separator is reflected by this outlet dryness value.

[0006] For example, Chinese Patent CN115235802A discloses a dryness test device for a gas-liquid separator and its test method, which includes a compressor, a condenser, an expansion valve, and an evaporator. It also includes a coaxial tube. The high-temperature and high-pressure inlet of the coaxial tube is connected to the outlet of the condenser, and the high-temperature and high-pressure outlet of the coaxial tube is connected to the inlet of the expansion valve. The outlet of the gas-liquid separator to be detected is connected to the low-temperature and low-pressure inlet of the coaxial tube, and the low-temperature and low-pressure outlet of the coaxial tube is connected to the suction port of the compressor. A first pressure and temperature sensor, a second pressure and temperature sensor, and a third pressure and temperature sensor are arranged in sequence at the high-temperature and high-pressure inlet, high-temperature and high-pressure outlet, and low-temperature and low-pressure outlet of the coaxial tube. During the test of this device, the first pressure and temperature value, the second pressure and temperature value, and the third pressure and temperature value are obtained through the first pressure and temperature sensor, the second pressure and temperature sensor, and the third pressure and temperature sensor, and the corresponding first enthalpy value, second enthalpy value, and third enthalpy value are obtained by looking up a table. The difference between the first enthalpy value and the second enthalpy value is the heating amount of the two-phase refrigerant at the outlet of the gas-liquid separator to be detected. Subtracting the heating amount from the third enthalpy value, the enthalpy value of the two-phase refrigerant at the outlet of the gas-liquid separator to be detected is obtained, and the dryness value here can be obtained by looking up a table.

[0007] In the above existing test method, after the gas-liquid separator to be tested is connected to the test system, it is directly detected. At this time, the working conditions of the test system are all in an unstable state, and there are many influencing factors during the test process. Under large-flow working conditions, the amount of mixed gas entering the gas-liquid separator per unit time increases significantly. More gas will carry liquid into the separator, causing a substantial increase in the input amount of liquid. Even if the separator has a certain separation ability, the influx of too much liquid in a short time causes the liquid level to rise rapidly, resulting in the components that promote gas-liquid separation, such as baffle plates in the gas-liquid separator, being unable to effectively separate the mixed gas, thus affecting the gas-liquid separation ability. Therefore, the existing test method is difficult to accurately reflect the gas-liquid separation ability of the gas-liquid separator to be tested.

[0008] On the other hand, in the existing test device, the outlet dryness value of the gas-liquid separator is directly obtained by looking up a table through the measured values of the first pressure and temperature sensor, the second pressure and temperature sensor, and the third pressure and temperature sensor. Since the distances between each pressure and temperature sensor and the gas-liquid separator to be tested are relatively far, there is pressure loss in the long pipeline, resulting in a reduction in the accuracy of the actual test results. Summary of the Invention

[0009] To overcome at least one of the above-mentioned defects in the prior art, the present invention provides a gas-liquid separation ability test system and test method for a gas-liquid separator, with a stable test system and high test accuracy.

[0010] The present invention provides a gas-liquid separation capacity test system for a gas-liquid separator, which includes a debugging loop formed by sequentially connecting a compressor, a condenser, a flowmeter, an OCR meter, an EXV electronic expansion valve, a first evaporator, a debugging station for connecting a first gas-liquid separator, and a second evaporator, and a test loop formed by sequentially connecting a compressor, a condenser, a flowmeter, an OCR meter, an EXV electronic expansion valve, a first evaporator, a test station for connecting a second gas-liquid separator, and a second evaporator; a first temperature and pressure sensor, a second temperature and pressure sensor, a third temperature and pressure sensor, and a fourth temperature and pressure sensor are respectively connected to the inlet end of the EXV electronic expansion valve, the outlet end of the first evaporator, the inlet end of the second evaporator, and the outlet end of the second evaporator; a first regulating valve and a second regulating valve are respectively connected to the pipelines between the inlet and the first outlet and between the outlet and the first inlet of the debugging station; a third regulating valve and a fourth regulating valve are respectively connected to the pipelines between the inlet and the second outlet and between the outlet and the second inlet of the test station.

[0011] As an improvement, a first pressure transmitter is connected to the pipeline between the first regulating valve and the first gas-liquid separator and near the inlet of the first gas-liquid separator, and a second pressure transmitter is connected to the pipeline between the second regulating valve and the first gas-liquid separator and near the outlet of the first gas-liquid separator; a third pressure transmitter is connected to the pipeline between the third regulating valve and the second gas-liquid separator and near the inlet of the second gas-liquid separator, and a fourth pressure transmitter is connected to the pipeline between the fourth regulating valve and the second gas-liquid separator and near the outlet of the second gas-liquid separator.

[0012] As a further improvement, the first regulating valve, the second regulating valve, the third regulating valve, and the fourth regulating valve are all manually adjustable ball valves. The structure is simple, the adjustment is convenient, and the cost is low.

[0013] As a further improvement, a visualization window for observing the internal gas-liquid separation state in real time is provided on the housing of the first gas-liquid separator. The visualization window facilitates the operator to directly observe the internal gas-liquid separation condition and judge whether the separation efficiency meets the requirements. Observe the liquid level height: it can directly see the liquid level height of the liquid in the liquid storage chamber of the gas-liquid separator, preventing the liquid from being too much or too little. Too high a liquid level may cause the liquid to enter the subsequent equipment with the gas, and too low a liquid level may affect the separation effect or cause poor oil return.

[0014] In addition, the present invention also provides a test method for a gas-liquid separation capacity test system of a gas-liquid separator, which includes the following steps: S1: Assemble the test device on the air-conditioning system bench, and connect the first gas-liquid separator and the second gas-liquid separator to the commissioning station and the test station respectively. The first gas-liquid separator is used as a commissioning part and will not be replaced later, while the second gas-liquid separator is used as a test part, and one to-be-tested gas-liquid separator is replaced after each test; S2: Evacuate the system. After the test system is set up, the first regulating valve, the second regulating valve, the third regulating valve, and the fourth regulating valve are all in the open state. The system starts to evacuate, and after the system pressure stabilizes, it is pressurized and maintained; S3: Refrigerant charging. After the system pressure holding is qualified, close the third regulating valve and the fourth regulating valve simultaneously. The first regulating valve and the second regulating valve remain open. The compressor runs, and the refrigerant fills the system pipeline and the auxiliary circuit where the commissioning station is located to form a commissioning system; Make the commissioning system reach the set equilibrium state, ensure that the refrigerant flow rate Q1 through the first gas-liquid separator, the inlet pressure P2 of the first gas-liquid separator, and the inlet dryness q1 respectively meet the set values, and record the working conditions at this time; The calculation formula for the inlet dryness is: In the formula: is the heat exchange capacity of the first evaporator; is the refrigerant flow rate; is the enthalpy value of the saturated liquid refrigerant at this state obtained by looking up the table according to the inlet pressure P2 of the first gas-liquid separator; is the enthalpy value of the saturated gaseous refrigerant at this state obtained by looking up the table according to the inlet pressure P2 of the first gas-liquid separator; is the enthalpy value obtained by looking up the table on the refrigerant physical property table according to the refrigerant temperature and pressure monitored by the first temperature and pressure sensor in front of the EXV electronic expansion valve; S4: Path switching. The debugging system remains in normal operation. Wait until the monitored numerical curves such as the refrigerant flow rate Q1 to be monitored, the inlet pressure P2 of the second gas-liquid separator, and the inlet dryness q1 reach a stable state, and the fluctuations of the numerical curves meet the error requirements. At the same time, close the first regulating valve and the second regulating valve. Meanwhile, open the third regulating valve and the fourth regulating valve simultaneously. The refrigerant is switched from the debugging circuit to the main circuit where the test station is located, forming a test system. When the system reaches a balanced state again, ensure that the refrigerant flow rate through the second gas-liquid separator is Q1, the inlet pressure of the second gas-liquid separator is P2, and the inlet dryness is q1. After the test is completed, record the refrigerant outlet pressure P2 of the second gas-liquid separator, obtain the enthalpy value at the outlet of the second gas-liquid separator by looking up the table, further obtain the outlet dryness q1' by looking up the table through the outlet enthalpy value, and determine the gas-liquid separation ability of the second gas-liquid separator in combination with the OCR value; The calculation formula for the inlet dryness is: In the formula: is the heat exchange amount of the first evaporator; is the refrigerant flow rate; is the enthalpy value of the saturated liquid refrigerant at this state obtained by looking up the table according to the inlet pressure P2 of the second gas-liquid separator; is the enthalpy value of the saturated gaseous refrigerant at this state obtained by looking up the table according to the inlet pressure P2 of the second gas-liquid separator; is the enthalpy value obtained by looking up the table on the refrigerant property table according to the refrigerant temperature and pressure monitored by the first temperature and pressure sensor in front of the EXV electronic expansion valve; The calculation formula for the outlet dryness is: In the formula: is the heat exchange amount of the second evaporator; is the refrigerant flow rate; is the enthalpy value of the saturated liquid refrigerant at this state obtained by looking up the table according to the outlet pressure P2 of the second gas-liquid separator; is the enthalpy value of the saturated gaseous refrigerant at this state obtained by looking up the table according to the outlet pressure P2 of the second gas-liquid separator; is the enthalpy value obtained by looking up the table on the refrigerant property table according to the refrigerant temperature and pressure monitored by the fourth temperature and pressure sensor at the outlet of the second evaporator; S5: After the test is completed, the third regulating valve and the fourth regulating valve are closed simultaneously. At the same time, the first regulating valve and the second regulating valve are opened simultaneously, and the refrigerant is switched back to the debugging system, and the compressor shuts down.

[0015] Preferably, in step S3, by adjusting the heating power of the first evaporator, ensure that the refrigerant flowing into the inlet of the gas-liquid separator reaches the set dryness value; at the same time, adjust the heating power of the second evaporator to ensure that the refrigerant flowing into the suction port of the compressor has a certain degree of superheat.

[0016] The above test system and test method of the present invention have the following advantages compared with the prior art: 1. An additional debugging gas-liquid separator for the debugging system is added, that is, an additional debugging loop is added. Before the formal test of the system, the refrigerant is first connected to the debugging system loop connected to the first gas-liquid separator. After ensuring the stability of the parameters of the debugging system, the refrigerant is then switched to the test system loop connected to the second gas-liquid separator, eliminating the influence caused by the unstable refrigerant circulation in the system at the beginning of the test, and effectively improving the test accuracy.

[0017] 2. The existing conventional evaporator is replaced by an evaporator with a voltage stabilizer source, and the control of the heating quantity is more accurate, thereby improving the test accuracy of the test system.

[0018] 3. The outlet pressure detection is realized through the pressure transmitter close to the gas-liquid separator to be tested, so as to obtain the outlet dryness of the gas-liquid separator to be tested. Compared with the existing test scheme, in which the outlet dryness of the gas-liquid separator is obtained through the measured values of the corresponding temperature and pressure sensors far away from the oil-gas separator to be tested, the influence of pressure loss caused by the pipeline is avoided, and the test accuracy of the system is improved.

[0019] Other improved features and advantages of the present invention will be described in the subsequent specific embodiments, and part of them will become obvious from the specification or be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures specifically pointed out in the specification and the drawings. Description of the Drawings

[0020] Figure 1 It is a schematic connection diagram of the gas-liquid separation ability test system of the gas-liquid separator of the present invention; Figure 2 is Figure 1 a schematic diagram of the refrigerant flow direction when the test system in Figure 3 is Figure 1 a schematic diagram of the refrigerant flow direction when the test system in Figure 4 is Figure 1Schematic diagram of refrigerant flow when the test system is in the test circuit.

[0021] Description of reference numerals: 1. Compressor; 2. Condenser; 3. Flowmeter; 4. OCR meter; 5. EXV electronic expansion valve; 6. First evaporator; 7. Second evaporator; 8. First temperature and pressure sensor; 9. Second temperature and pressure sensor; 10. Third temperature and pressure sensor; 11. Fourth temperature and pressure sensor; 12. First regulating valve; 13. Second regulating valve; 14. Third regulating valve; 15. Fourth regulating valve; 16. First pressure transmitter; 17. Second pressure transmitter; 18. Third pressure transmitter; 19. Fourth pressure transmitter; 20. First gas-liquid separator; 21. Second gas-liquid separator. Detailed implementation manners

[0022] First of all, those skilled in the art should understand that these implementation manners are only used to explain the technical principles of the embodiments of the present application, and are not intended to limit the protection scope of the embodiments of the present application. Those skilled in the art can make adjustments according to needs to adapt to specific application scenarios.

[0023] In the description of the embodiments of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "fixed" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific situations.

[0024] The present application will be further described in detail below with reference to the drawings and specific embodiments.

[0025] See Figures 1 to 4As shown in the figure, the embodiments of the present application disclose a gas-liquid separation capacity test system for a gas-liquid separator. The device includes a compressor 1, a condenser 2, a flow meter 3, an OCR meter 4, an EXV electronic expansion valve 5, a first evaporator 6, a debugging station for connecting to a first gas-liquid separator 20, a test station for connecting to a second gas-liquid separator 21, and a second evaporator 7. Among them, the outlet of the compressor 1 is connected to the outlet of the condenser 2, the outlet of the condenser 2 is connected to the inlet of the flow meter 3, the outlet of the flow meter 3 is connected to the inlet of the OCR meter 4. The flow meter 3 is used to monitor the refrigerant flow in the entire test system. The outlet of the OCR meter 4 is connected to the inlet of the EXV electronic expansion valve 5. The EXV electronic expansion valve 5 is a key component in the refrigeration system and can precisely control the refrigerant flow, thus ensuring the efficient and stable operation of the refrigeration system. The first outlet of the first evaporator 6 is connected to the inlet of the debugging station, the outlet of the debugging station is connected to the first inlet of the second evaporator 7, and the outlet of the second evaporator 7 is connected to the inlet of the compressor 1 to form a debugging loop. Additionally, the second outlet of the first evaporator 6 is connected to the inlet of the test station, the outlet of the test station is connected to the second inlet of the second evaporator 7, and the outlet of the second evaporator 7 is connected to the inlet of the compressor 1 to form a test loop. In this structure, all components are connected through refrigerant circulation pipelines.

[0026] Additionally, a first temperature and pressure sensor 8, a second temperature and pressure sensor 9, a third temperature and pressure sensor 10, and a fourth temperature and pressure sensor 11 are respectively connected to the pipelines at the inlet end of the EXV electronic expansion valve 5, the outlet end of the first evaporator 6, the inlet end of the second evaporator 7, and the outlet end of the second evaporator 7. The outlet of the first evaporator 6 is divided into a first outlet and a second outlet after passing through the second temperature and pressure sensor 9. The inlet end of the second evaporator 7 has a first inlet and a second inlet before the third temperature and pressure sensor 10. A first regulating valve 12 and a second regulating valve 13 are respectively connected to the pipelines between the inlet of the debugging station and the first outlet and between the outlet and the first inlet. A third regulating valve 14 and a fourth regulating valve 15 are respectively connected to the pipelines between the inlet of the test station and the second outlet and between the outlet and the second inlet.

[0027] The first temperature and pressure sensor 8 is used to monitor the temperature and pressure of the refrigerant before the EXV electronic expansion valve 5. The second temperature and pressure sensor 9 is used to monitor the temperature and pressure of the refrigerant at the outlet of the first evaporator 6. The third temperature and pressure sensor 10 is used to detect the temperature and pressure of the refrigerant at the inlet of the second evaporator 7. The fourth temperature and pressure sensor 11 is used to detect the temperature and pressure of the refrigerant at the outlet of the second evaporator 7.

[0028] More specifically, in this embodiment, a first pressure transmitter 16 is connected to the pipeline between the first regulating valve 12 and the first gas-liquid separator 20 and near the inlet of the first gas-liquid separator 20, and a second pressure transmitter 17 is connected to the pipeline between the second regulating valve 13 and the first gas-liquid separator 20 and near the outlet of the first gas-liquid separator 20; a third pressure transmitter 18 is connected to the pipeline between the third regulating valve 14 and the second gas-liquid separator 21 and near the inlet of the second gas-liquid separator 21, and a fourth pressure transmitter 19 is connected to the pipeline between the fourth regulating valve 15 and the second gas-liquid separator 21 and near the outlet of the second gas-liquid separator 21. In this system, the pressure values at the inlet and outlet of the first gas-liquid separator 20 are obtained through the first pressure transmitter 16 and the second pressure transmitter 17, the corresponding first enthalpy value and second enthalpy value are obtained by looking up a table, and then the inlet dryness q1 and outlet dryness q1' corresponding to the inlet and outlet of the first gas-liquid separator 20 are obtained by looking up a table according to the enthalpy value situation. Similarly, the third pressure transmitter 18 and the fourth pressure transmitter 19 are used to obtain the inlet dryness q1 and outlet dryness q1' at the inlet and outlet of the second gas-liquid separator 21.

[0029] On the other hand, preferably in the above structure, both the first evaporator 6 and the second evaporator 7 are calorimeters with a voltage stabilizer. It is essentially an electric heating device that can accurately control the heating amount. Its basic principle is to use the current passing through the resistance wire to generate heat, and then transfer the heat to the refrigerant through heat conduction. When the electric heater is powered on, the resistance wire starts to heat up, the surrounding temperature rises, and the heat will be transferred to the refrigerant in contact with it, thereby increasing the temperature of the refrigerant. The temperature control accuracy is high. Before the evaporator is used, the heat leakage amount should be calibrated. The calibration of the evaporator heat leakage amount refers to the process of determining the heat leakage rate caused by the temperature difference with the external environment when there is no internal heating or cooling source acting on the evaporator. Accurate heat leakage amount calibration can improve the accuracy of evaporator measurement. When measuring the heat absorption or heat release of the refrigerant, if the influence of the heat leakage amount is not considered, the measurement result may have a large deviation. Only by accurately knowing the heat leakage amount can it be corrected in actual measurement, so as to obtain more accurate refrigerant heat change data.

[0030] In this embodiment, a voltage stabilizer is added compared with the conventional evaporator. Adding a voltage stabilizer in the evaporator mainly has the following functions and meanings:

[0031] Stabilize the heating power: In the experiment of measuring the mechanical equivalent of heat by the electric heating method, it is necessary to heat the liquid in the evaporator through the resistance wire. The voltage stabilizer can ensure that the voltage applied across the resistance wire is stable. According to \(P = UI\) (where \(P\) is power, \(U\) is voltage, and \(I\) is current), the heating power of the resistance wire can be kept constant, and then the heat absorption rate of the evaporator system can be stabilized, improving the accuracy and repeatability of the experimental results.

[0032] Reducing systematic errors: Unstable voltage may cause uneven heating of the liquid or object in the evaporator, resulting in local overheating or overcooling, inaccurate temperature measurement, and introducing systematic errors.

[0033] The voltage stabilizer can avoid this situation, make the internal temperature of the evaporator rise or fall evenly, improve the accuracy of temperature measurement, and reduce systematic errors. In this embodiment, through the calorimeter, parameters such as the power and time of electric heating can be precisely controlled to achieve precise adjustment of the heating amount, so as to accurately control the temperature of the heated medium, with a relatively high temperature control accuracy, which can well meet the requirements in some experiments with strict temperature requirements.

[0034] The first regulating valve 12, the second regulating valve 13, the third regulating valve 14, and the fourth regulating valve 15 involved in this embodiment are all manual regulating ball valves, which have a simple structure, are convenient for flexible switching between the debugging circuit and the test circuit, and have a low cost.

[0035] Furthermore, the first gas-liquid separator 20 in this embodiment is provided with a visualization window. The presence of the visualization window does not affect its basic separation principle, but it is convenient for the operator to observe the height of the refrigerant liquid level inside in real time, that is, to observe the separation process and effect, and judge whether the separation efficiency meets the requirements. Too high a liquid level may cause the liquid to enter the subsequent equipment with the gas, and too low a liquid level may affect the separation effect or cause poor oil return.

[0036] On the other hand, this application embodiment also provides a test method for the gas-liquid separation ability test system of a gas-liquid separator, which mainly includes the following steps: S1: Assemble the test device on the air-conditioning system bench. First, pre-assemble the test device, and then connect the first gas-liquid separator 20 and the second gas-liquid separator 21 to the debugging station and the test station respectively. The first gas-liquid separator 20 is used as a debugging part and will not be replaced later, and the second gas-liquid separator 21 is used as a test part, and one is replaced after each test; S2: Evacuate the system. After the test system is built, the first regulating valve 12, the second regulating valve 13, the third regulating valve 14, and the fourth regulating valve 15 are all in the open state. The system starts to evacuate, and after the system pressure is stable, keep the pressure. For the system path, please refer to the appendix Figure 2 ; S3: Refrigerant filling. After the system passes the pressure retention test, close the third regulating valve 14 and the fourth regulating valve 15 at the same time. The first regulating valve 12 and the second regulating valve 13 remain open. The compressor 1 runs, and the refrigerant fills the system pipeline and the auxiliary circuit where the debugging station is located to form a debugging system; make the debugging system reach the set equilibrium state, ensure that the refrigerant flow rate Q1 through the first gas-liquid separator 20, the inlet pressure P2 of the first gas-liquid separator 20, and the inlet dryness q1 respectively meet the set values, and record the working conditions at this time; The calculation formula for the inlet dryness is as follows: In the formula: is the heat exchange amount of the first evaporator 6; is the refrigerant flow rate; is the enthalpy value of the saturated liquid refrigerant at this state obtained by looking up the table according to the inlet pressure P2 of the first gas-liquid separator 20; is the enthalpy value of the saturated gaseous refrigerant at this state obtained by looking up the table according to the inlet pressure P2 of the first gas-liquid separator 20; is the enthalpy value obtained by looking up the table on the refrigerant property table according to the refrigerant temperature and pressure monitored by the first temperature and pressure sensor 8 in front of the EXV electronic expansion valve 5; In this step, by adjusting the heating power of the first evaporator 6, ensure that the refrigerant flowing into the inlet of the gas-liquid separator reaches the set dryness value of 0.8 - 1; at the same time, adjust the heating power of the second evaporator 7 to ensure that the refrigerant flowing into the suction port of the compressor has a superheat degree of 10 - 20 °C to prevent liquid slugging of the compressor; The OCR meter 4 is used to monitor the oil circulation rate of the refrigerant in the connecting pipeline of the test bench system. The refrigerant oil circulation rate OCR refers to the proportion of the mass or volume of the compressor lubricating oil contained in the refrigerant to the total amount of the refrigerant; the oil circulation heat transfer coefficient of the air-conditioning system decreases; since the temperature of the refrigerant in the evaporator is lower than that of the condenser 2, the viscosity of the oil is relatively large, resulting in a relatively large increase in the heat transfer resistance and a relatively large attenuation of heat. When the heat pump operates in the low-temperature heating mode, the evaporation temperature is lower and the viscosity of the oil is greater, and the influence is more serious; S4: Path switching. Keep the debugging system running normally. Wait until the monitored numerical curves such as the refrigerant flow rate Q1, the inlet pressure P2 of the second gas-liquid separator 21, and the inlet dryness q1 reach a stable state, and the fluctuations of the numerical curves meet the error requirements. At the same time, close the first regulating valve 12 and the second regulating valve 13. Meanwhile, open the third regulating valve 14 and the fourth regulating valve 15 at the same time. The refrigerant is switched from the debugging circuit to the main circuit where the test station is located to form a test system; when the system reaches a balanced state again, ensure that the refrigerant flow rate passing through the second gas-liquid separator 21 is Q1, the inlet pressure of the second gas-liquid separator 21 is P2, and the inlet dryness is q1. After the test, record the refrigerant outlet pressure P2 of the second gas-liquid separator 21, obtain the enthalpy value at the outlet of the second gas-liquid separator 21 by looking up the table, further obtain the outlet dryness q1' by looking up the table through the outlet enthalpy value, and combine the OCR value to determine the gas-liquid separation ability of the second gas-liquid separator 21; The calculation formula for the inlet dryness is as follows: Wherein: is the heat exchange capacity of the first evaporator 6; is the refrigerant flow rate; is the enthalpy value of the saturated liquid refrigerant at this state obtained by looking up the table according to the inlet pressure P2 of the second gas-liquid separator 21; is the enthalpy value of the saturated gaseous refrigerant at this state obtained by looking up the table according to the inlet pressure P2 of the second gas-liquid separator 21; is the enthalpy value obtained by looking up the table on the refrigerant property table according to the refrigerant temperature and pressure monitored by the first temperature and pressure sensor 8 in front of the EXV electronic expansion valve 5; The calculation formula for the outlet dryness is: Wherein: is the heat exchange capacity of the second evaporator 7; is the refrigerant flow rate; is the enthalpy value of the saturated liquid refrigerant at this state obtained by looking up the table according to the outlet pressure P2 of the second gas-liquid separator 21; is the enthalpy value of the saturated gaseous refrigerant at this state obtained by looking up the table according to the outlet pressure P2 of the second gas-liquid separator 21; is the enthalpy value obtained by looking up the table on the refrigerant property table according to the refrigerant temperature and pressure monitored by the fourth temperature and pressure sensor 11 at the outlet of the second evaporator 7; S5: After the test is completed, the third regulating valve 14 and the fourth regulating valve 15 are closed simultaneously. At the same time, the first regulating valve 12 and the second regulating valve 13 are opened simultaneously, and the refrigerant is switched back to the debugging system again, and the compressor 1 stops.

[0037] Compared with the prior art, the above test system and test method of the present application add a debugging loop, that is, in addition to the normal test loop, a first gas-liquid separator 20 for the debugging system is added. Before the system test, the refrigerant is connected to the debugging system loop connected to the first gas-liquid separator 20. After ensuring the stability of the parameters of the debugging system, the refrigerant is switched to the test system loop connected to the second gas-liquid separator 21, eliminating the influence of the unstable refrigerant circulation in the test system at the beginning and effectively improving the test accuracy.

[0038] In addition, in the test system of the present application, the existing conventional evaporator is replaced by an evaporator with a voltage stabilizer, and the control of the heating amount is more accurate, thereby improving the test accuracy of the test system.

[0039] On the other hand, in the test system of the present application, the outlet pressure is detected by a pressure transmitter close to the gas-liquid separator to be tested, so as to obtain the outlet dryness of the gas-liquid separator to be tested. Compared with the existing test scheme in which the outlet dryness of the gas-liquid separator is obtained through the measured values of the corresponding temperature and pressure sensors far away from the oil-gas separator to be tested, the influence of pressure loss caused by the pipeline is avoided, and the test accuracy of the system is improved.

[0040] In the description of the present application, the reference to the term "this embodiment" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0041] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed by the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A gas-liquid separation capacity test system for a gas-liquid separator, characterized in that: It includes a debugging loop formed by sequentially connecting a compressor, a condenser, a flowmeter, an OCR meter, an EXV electronic expansion valve, a first evaporator, a debugging station for connecting a first gas-liquid separator, and a second evaporator, and a testing loop formed by sequentially connecting a compressor, a condenser, a flowmeter, an OCR meter, an electronic expansion valve, a first evaporator, a testing station for connecting a second gas-liquid separator, and a second evaporator; a first temperature and pressure sensor, a second temperature and pressure sensor, a third temperature and pressure sensor, and a fourth temperature and pressure sensor are respectively connected to the inlet end of the electronic expansion valve, the outlet end of the first evaporator, the inlet end of the second evaporator, and the outlet end of the second evaporator; a first regulating valve and a second regulating valve are respectively connected to the pipelines between the inlet and the first outlet and between the outlet and the first inlet of the debugging station; a third regulating valve and a fourth regulating valve are respectively connected to the pipelines between the inlet and the second outlet and between the outlet and the second inlet of the testing station.

2. The gas-liquid separation capacity test system of the gas-liquid separator according to claim 1, wherein: A third pressure transmitter is connected to the pipeline between the first regulating valve and the first gas-liquid separator and near the inlet of the first gas-liquid separator, and a fourth pressure transmitter is connected to the pipeline between the second regulating valve and the first gas-liquid separator and near the outlet of the first gas-liquid separator; a first pressure transmitter is connected to the pipeline between the third regulating valve and the second gas-liquid separator and near the inlet of the second gas-liquid separator, and a second pressure transmitter is connected to the pipeline between the fourth regulating valve and the second gas-liquid separator and near the outlet of the second gas-liquid separator.

3. The gas-liquid separation capacity test system of the gas-liquid separator according to claim 1 or 2, characterized in that Both the first evaporator and the second evaporator are calorimeters with a voltage stabilizing source.

4. The gas-liquid separation capacity test system of the gas-liquid separator according to claim 1, characterized in that: The first regulating valve, the second regulating valve, the third regulating valve, and the fourth regulating valve are all manual regulating ball valves.

5. The testing method of the gas-liquid separation capacity testing system of the gas-liquid separator according to claim 1, characterized in that: A visualization window for observing the internal refrigerant liquid level height in real time is provided on the shell of the first gas-liquid separator.

6. A test method for a gas-liquid separation ability test system of the gas-liquid separator according to claim 1, characterized in that, It includes the following steps: S1: Assemble the test device on the air-conditioning system bench, connect the first gas-liquid separator and the second gas-liquid separator to the debugging station and the testing station respectively. The first gas-liquid separator is used as a debugging component and will not be replaced later, and the second gas-liquid separator is used as a test component, and a to-be-tested gas-liquid separator is replaced after each test. S2: Evacuate the system. After the test system is built, the first regulating valve, the second regulating valve, the third regulating valve, and the fourth regulating valve are all in the open state. The system starts to evacuate, and after the system pressure is stable, it is pressurized and maintained. S3: Refrigerant charging. After the system pressure holding is qualified, the third regulating valve and the fourth regulating valve are closed simultaneously, the first regulating valve and the second regulating valve remain open, the compressor runs, and the refrigerant fills the system pipeline and the auxiliary loop where the debugging station is located to form a debugging system; make the debugging system reach the set equilibrium state, ensure that the refrigerant flow rate Q1 through the first gas-liquid separator, the inlet pressure P2 of the first gas-liquid separator, and the inlet dryness q1 respectively meet the set values, and record the working conditions at this time. The calculation formula for the inlet dryness is: In the formula: is the heat exchange amount of the first evaporator; is the refrigerant flow rate; Based on the inlet pressure P2 of the first gas-liquid separator, the enthalpy value of the saturated liquid refrigerant in this state is obtained by looking up the table; According to the inlet pressure P2 of the first gas-liquid separator, the enthalpy value of the saturated gaseous refrigerant in this state is obtained by looking up the table; Based on the refrigerant temperature and pressure monitored by the first temperature and pressure sensor in front of the EXV electronic expansion valve, its enthalpy value is obtained by looking up the refrigerant property table. S4: Path switching. The debugging system remains in normal operation. Wait until the monitored numerical curves such as the refrigerant flow rate Q1 to be monitored, the inlet pressure P2 of the second gas-liquid separator, and the inlet dryness q1 reach a stable state, and the fluctuations of the numerical curves meet the error requirements. At the same time, close the first regulating valve and the second regulating valve. Meanwhile, open the third regulating valve and the fourth regulating valve simultaneously. The refrigerant is switched from the debugging circuit to the main circuit where the test station is located, forming a test system. When the system reaches a balanced state again, ensure that the refrigerant flow rate through the second gas-liquid separator is Q1, the inlet pressure of the second gas-liquid separator is P2, and the inlet dryness is q1. After the test is completed, record the refrigerant outlet pressure P2 of the second gas-liquid separator, obtain the enthalpy value at the outlet of the second gas-liquid separator by looking up the table, further obtain the outlet dryness q1' by looking up the table through the outlet enthalpy value, and determine the gas-liquid separation ability of the second gas-liquid separator in combination with the OCR value; The calculation formula for the inlet dryness is: In the formula: is the heat exchange amount of the first evaporator; is the refrigerant flow rate; According to the inlet pressure P2 of the second gas-liquid separator, the enthalpy value of the saturated liquid refrigerant in this state is obtained by looking up the table; Based on the inlet pressure P2 of the second gas-liquid separator, the enthalpy value of the saturated gaseous refrigerant in this state is obtained by looking up the table; Based on the refrigerant temperature and pressure monitored by the first temperature and pressure sensor in front of the EXV electronic expansion valve, its enthalpy value is obtained by looking up the refrigerant property table. The calculation formula for the outlet dryness is: In the formula: is the heat exchange amount of the second evaporator; is the refrigerant flow rate; Based on the outlet pressure P2 of the second gas-liquid separator, the enthalpy value of the saturated liquid refrigerant in this state is obtained by looking up the table; Obtain the enthalpy value of the saturated gaseous refrigerant at this state by looking up the table according to the outlet pressure P2 of the second gas-liquid separator; Based on the refrigerant temperature and pressure monitored by the fourth temperature and pressure sensor at the outlet of the second evaporator, its enthalpy value is obtained by looking up the refrigerant physical property table. S5: After the test is completed, close the third regulating valve and the fourth regulating valve simultaneously. Meanwhile, open the first regulating valve and the second regulating valve simultaneously. The refrigerant is switched to the debugging system again, and the compressor shuts down.

7. The testing method of the gas-liquid separation capacity testing system of the gas-liquid separator according to claim 6, characterized in that: In step S3, by adjusting the heating power of the first evaporator, ensure that the refrigerant flowing into the inlet of the gas-liquid separator reaches the set dryness value; at the same time, adjust the heating power of the second evaporator to ensure that the refrigerant flowing into the suction port of the compressor has a certain degree of superheat.

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