Carbon dioxide compressor performance test system with trans/subcritical test function

Abstract

The invention relates to the field of carbon dioxide compressor performance tests, in particular to a carbon dioxide compressor performance test system with a transcritical / subcritical testing function. The system involves a test loop, wherein the test loop is formed on a main pipeline together with a to-be-tested carbon dioxide compressor; and the test loop comprises a first switching valve, a second switching valve, a third switching valve and a fourth switching valve which are arranged in sequence, wherein a transcritical circulating gas cooling section and a subcritical circulating condensation section which are connected in parallel are arranged between the first switching valve and the second switching valve, a transcritical circulating evaporation section and a subcritical circulating evaporation section which are connected in parallel are arranged between the third switching valve and the fourth switching valve, and the main pipeline is further provided with an adjusting and measuring assembly. The system has the advantages that the system covers the large-scale working conditions of the carbon dioxide compressor in transcritical / subcritical circulating, so that equipment used by test equipment is reduced, and the cost is reduced; and when different circulating tests are carried out through the same machine, disassembling and assembling of the machine are not needed, sothat operation is simpler and more convenient.

Description

technical field [0001] The invention relates to the field of performance testing of carbon dioxide compressors, in particular to a performance testing system of carbon dioxide compressors with the function of trans / subcritical testing. Background technique [0002] As a natural and environmentally friendly refrigerant that does not destroy the atmospheric ozone layer (ODP=0) and has a small global warming index (GWP=1), carbon dioxide has good thermodynamic properties and is one of the main directions of research on alternative refrigerants in recent years. . The carbon dioxide compressor has the characteristics of high working pressure, large pressure difference, and small pressure ratio. The working medium pressure in the system is 5 to 10 times that of the traditional working medium. The national standard GB / T 5773 stipulates that the performance test methods of positive displacement refrigerant compressors should include two methods with different test principles and me...

AI Technical Summary

Problems solved by technology

Taking the common primary side adopting the second refrigerant calorimeter method and the auxiliary side adopting the refrigerant liquid flowmeter method as an example, due to the high pressure of the working medium in the carbon dioxide refrigerant system, if the transcritical cycle and For the test of subcritical cycle, the withstand voltage capacity of the whole system needs to be greatly improved, and the cost of test equipment will also increase significantly

At the same time, due to the low critical temperature of carbon dioxide (about 31°C), when the ambient temperature is high and the temperature inside the reservoir is higher than the critical temperature, the carbon dioxide in the reservoir cannot maintain a liquid state, and the internal pressure of the reservoir increases significantly. Large, easy to cause the safety valve to jump and have the risk of explosion

On the other hand, in the subcritical cycle of carbon dioxide, the temperature of the condensation side is usually below 0°C, and the conventional water-cooled condenser is not suitable for the test system of the carbon dioxide compressor

In the transcritical cycle of carbon dioxide, the cooling process is gas cooling, and the pressure and temperature of the working fluid are relatively independent variables. The temperature of the cooling medium cannot be used to adjust the exhaust pressure, and the test system needs to be modified.

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