The Research Of Variable Flow Two-stage Compression Refrigeration Cycle

This article through analyze to the existing two-stage compression for frozen cold storage refrigeration system,Using EES software calculate the coefficient of among the four kinds of two-stage compression refrigeration system and high and low pressure under the middle of the best pressure. Through mathematical modeling to compares four ways,preliminary concluded that the refrigeration coefficient of two-stage compression refrigeration system is the largest one under the same conditions.In this paper, the test has carried on the design on the basis of the theoretical calculation results, sets up a test-bed which can realize four circular manner by controlling the hand valve.the test-bed is consists of refrigeration units and indoor and outdoor environment simulation system. Using the R410 A Compressor which is rotor type Based on DC Frequency Conversion Technology, water cooled condenser, electronic expansion valve,using thermal equilibrium method to test the Refrigerating capacity. This test-bed collects the data of each operating point in the system through the Windows Control Center configuration software. the Performance of test bed was tested by thermal equilibrium method, to determine the optimum intermediate pressure under different working conditions and statistics shows high and low pressure flow ratio and coefficient of cooling performance in the different condition.The analysis of experimental data is that the refrigeration coefficient firstly increases and then decreases with the increase of middle pressure, increases with the increase of evaporation temperature, decreases with the increase condensation temperature.Finally will get the changing rule of the ratio between the refrigeration coefficient and high-low pressure flow at the experiment is compared with the simulation results, found that the changing trend of experimental value and simulation values is consistent.The purpose of this experiment is to constant frozen cold storage temperature, Keep frozen food at a constant frozen rate and reduce the dry food consumption.