Study On The Coupling Optimization Of Solar-soil Source Heat Pump System In Cold Region

Because of its high efficiency,environmental protection and energy saving,soil-source heat pump has been used more and more in the construction field.In cold region,using solar energy as the auxiliary heat source,while reached a certain amount of energy saving effect,the performance of the solar energy and soil source heat pump coupling problem,have not been able to get a good solution.This subject mainly research the solar-coupling application of soil source heat pump system in cold region,optimize the existing winter heating system,ultimately for the heating system in practical engineering optimization scheme is put forward.In this paper,TRNSYS software is used to model the system,and the practical engineering design parameters are used to simulate the initial parameters of the simulation,and compare the simulation data with the measured data to verify the rationality of the model.This paper analyzes the temperature change of heat storage tank in heating season and the relationship between heating temperature of unit,and divides the whole heating season into three heating stages.Comparing two operating modes each heating stage evaporator inlet temperature and COP units,heat pump unit quantity of heat,heat exchanger,radiator heating load and heat collector sets,the system’s COP and power consumption,the soil temperature change,analysis of advantages and disadvantages of each mode determine the optimal operating mode of the system.After determining the operation mode,the control strategy is optimized,and the optimal operation scheme is finally determined.According to the calculation results,it is concluded that operation mode 2 is superior to the mode one in operating effect and energy saving in the system.However,in the early stage of heating,in the middle stage,and in the late stage,the mode is less than the mode 2 when it meets the requirements of building heating.It is found that operation mode 2 is suitable for heating medium in the middle stage of heating.Combined with the whole heating season power consumption and the operation of the two modes in different heating stage characteristics,finally to determine the optimal operating mode for the heating used the end of the first mode operation,heating medium use mode 2 run;Heating water tank open straight at the beginning of the end heat storage water tank for time stop temperature 41℃and37℃,respectively,in the middle of the heating series runtime delta T_L2=0℃,delta T_u2=8℃.In the above optimization scheme,the whole heating season system consumes 50942.34 kwh,saving 3169.9 kwh,saving 5.86%,and the system COP is4.04,which is 0.81.