Performance Analysis And Improvement Strategy Of Air Source Heat Pump System

The electrically driven air source heat pump uses air as a low-temperature heat source,and has the characteristics of no pollutant emission,which is in line with the ideal heating mode.Especially in the transitional seasons of spring and autumn,in rural areas,suburbs and other places where central heating is not perfect,the air source heat pump has the advantages of strong adjustability and convenient use.However,when ordinary air source heat pumps operate at an ambient temperature below-10℃,problems such as insufficient heating capacity,low energy efficiency ratio(COP),and even inability to operate for a long time occur.Among the many improvements,the air source heat pump system that adds a regenerator between the evaporator and the condenser to increase heat exchange is considered to be a technically reasonable and practical solution.However,after research,it has been found that the regenerative system still has the problem of low system energy efficiency ratio(COP)when the ambient temperature fluctuates in a wide range(the temperature difference between the highest point and the lowest point of the day is greater than 12℃).Thermal system COP,the researcher proposed an air source heat pump system with double regenerators.The main work is reflected in the following aspects:First,establish the steady-state theoretical model of the heat pump system based on the mathematical models of the compressor,condenser,evaporator,and expansion valve,and theoretically reason about the impact of ambient temperature and superheat on the system performance measurement value(energy efficiency ratio(COP));Use the Dymola simulation platform to build an air source heat pump system model,conduct simulation research on it,and analyze the influence of ambient temperature and superheat on the main parameters of the system and the system energy efficiency ratio(COP).Secondly,use laboratory air source heat pump system equipment to conduct experiments to accurately understand the performance law of the heat pump system under different working conditions and verify the correctness of the system simulation model based on the Dymola simulation platform.Compare and analyze the test results and simulation results of system performance measurement values(energy efficiency ratio(COP)),compressor discharge temperature,system heating capacity,mass flow,and input power.The test results are basically consistent with the trends of the simulation results.Finally,according to the influence of superheat on system performance,a regenerative system with a strong ability to control superheat is used for research.Through the change of evaporation temperature,the exhaust temperature,heating capacity,mass flow and energy efficiency of the regenerative system are calculated.The change law of parameters such as ratio(COP);according to the superheat of different sizes of regenerators simulated,a double regenerator heat recovery system is proposed,and the exhaust gas of the double regenerator heat recovery system after the evaporation temperature changes is calculated again.Changes in parameters such as air temperature,heating capacity,mass flow,and energy efficiency ratio(COP).Obtained,when the ambient temperature is-30℃,the heating capacity of the double regenerator heat recovery system is increased by 23.2%and 13.7%,respectively,and the COP increased by 14.3%and 8.6%,respectively.The research in this paper and the proposal of the air source heat pump system with dual regenerators will help solve the problem of the influence of the wide range of ambient temperature fluctuations on the performance of the air source heat pump system in the northern region.