Experimental Study On The Performance Of A New Type Of Refrigeration System For Cold Storage Based On R410A Assembly Type Large Temperature Difference

Regarding the vapor compression cold storage refrigeration system,there are common problems such as high compressor discharge temperature,low refrigeration performance,high system energy consumption,and ozone layer destruction caused by refrigerant,A new type of refrigeration system experiment platform for cold storage based on R410 A assembly type large temperature difference was built.The clean azeotropic point mixed refrigerant R410 A is used.The air supplement method adopts medium pressure air supplement technology.The compressor adopts a dual-rotor compressor.Microchannel heat exchanger is used in evaporator and condenser.By adjusting the superheat value of the main circuit electronic expansion valve,the superheat value of the supplementary circuit electronic expansion valve,the air supply mode,the compressor speed,the ambient temperature outside the warehouse and the ambient temperature inside the warehouse,the effects of medium pressure air supply and no air supply on the compressor exhaust temperature,exhaust pressure,refrigerating capacity,compressor power,the opening of the electronic expansion valve,COP,EER and other performance of the new refrigeration system for cold storage were analyzed Ring.The conclusions are as follows:(1)In the process of the main valve superheat value from 2K to 8K,the main valve opening and compressor power gradually decrease,and the compressor discharge temperature gradually rises.When the main valve superheat value is 6K,the maximum cooling capacity is 4.04 k W,the maximum COP value is 1.79,and the maximum EER is 1.32;(2)During the process of the superheat of the supplementary valve from 5K to 35 K,the supplementary valve opening and compressor power gradually decrease,the compressor discharge temperature,cooling capacity,system COP,system EER gradually increase,and the supplementary valve superheat When it is 25 K,the performance of the system is better;(3)Comparing medium-pressure supplemental air and no supplemental air,the compressor discharge temperature drops by 37.56%,the system cooling capacity increases by 28.96%,and the compressor power increases by 27.43%.The system COP and system EER are both more than non-compensated high gas.(4)With the increase of compressor speed in the medium-pressure air supplement and non-air supplement systems,the compressor discharge temperature,system refrigeration capacity,and compressor power all show an increasing trend,and the system COP and system EER all show a downward trend;(5)The temperature outside the warehouse changes from 21°C,27°C,32°C,35°C and 43°C.The COP of the medium pressure air supplement system decreases by 15.64%,11.71%,13.26%,28.03%;the outside environment When the temperature is 43,the medium-pressure supplemental gas exhaust temperature is 75.31,and the nonsupplementary system cannot work because the exhaust temperature is too high;(6)With the decrease of the ambient temperature in the warehouse,the performance changes of the system with and without intermediate pressure compensation are the same.The discharge temperature of the compressor increases,while the refrigeration capacity,compressor power,cop and eer decrease.The refrigeration performance of the refrigeration system gradually deteriorates.When the ambient temperature in the warehouse is-21,only the medium pressure compensation system can work normally.