Research On The Performance Test Equipments Of Refrigeration Compressor And Refrigeration Heat-exchanger

Improving the energy efficiency of refrigeration products is a major issue in refrigeration industry. Performance test equipment is necessary for testing and researching the performance of refrigeration compressor and refrigeration heat exchanger. This paper analysed the refrigeration compressor and heat exchanger performance testing theory, then developed a set of refrigeration compressor performance test equipment using the second refrigerant heat meter method and liquid refrigerant mass meter method, and also developed a set of refrigeration heat exchanger performance test equipment using the air enthalpy different method and liquid refrigerant mass meter method. The heat exchanger performance test equipment can also test the cooling capacity of air-cooled or water-cooled condensing units under different operation conditions using the water cooling method and liquid refrigerant mass meter method.In the test equipment, PID regulation devices were used to control test conditions. This paper designed the equipment control software using Visual Basic language. Through establishing communication with data acquisition, PLC and PID regulator, the control software can collect data, analye results, set test condition and control equipment automatically. The software calculated the thermodynamic properties of refrigerant using polynomial fitting formula based on Cleland model. This paper fitted polynomial coefficients of R404A, and the test equipment can meet the testing requirements of R410A, R407C, R404A, R22 and R134a refrigerants.This paper researched the proper control strategy to ensure the rapid and stable of the test condition when developed the refrigeration compressor performance test equipment. Through in-depth analysis of the test principle and rational design of the refrigeration system, the test equipment can get accurate and reliable test results.The measurement results and errors were also analyzed and summarized in this paper. In addition, this paper also reseachered the performance of inverter compressor under the different experimental conditions. The results showed that the performance of inverter compressor mainly determined by the operating conditions. The COP was largest in the base frequency of compressor, when the frequency deviated from the base frequency, the COP decreased. Different from the traditional structure of test equipment, the refrigeration heat exchanger performance test equipment was made up of a refrigerant operation condition machine and an air-enthalpy test room. According to the control requirements, the test equipment used two electronic expansion valve with a double-flow bypass system to control the condensing temperature and subcooling, evaporating temperature and superheat stability. This paper analyed and solved the main problems encountered of the test equipment. Finally, this paper analysed the measurement results of the equipment. The results showed that the test equipment can control test condition stablely, measure results accurately, and achieved acceptance criteria.