基于不同动态负荷的太阳能辅助地源热泵系统供暖特性研究

建立了太阳能辅助地源热泵系统(SAGSHPS)动态仿真模型,基于间歇负荷1(8:00-20:00末端开启)、间歇负荷2(18:00-次日7:00末端开启)和连续负荷(末端全天24h开启)条件,对大连地区SAGSHPS在整个供暖期内的运行过程分别进行逐时动态仿真,分析了3种典型动态负荷下SAGSHPS的运行特性.结果表明:冬季最冷日内不同负荷下,系统供暖运行方式不同.间歇负荷1下系统以地源热泵(GSHP)和太阳能热泵(SHP)交替供暖;间歇负荷2下系统以地源热泵供暖为主,只在入夜初期辅以太阳能热泵供暖;连续负荷下系统白天以太阳能热泵供暖,夜间以地源热泵供暖.整个供暖期内,蒸发器入口温度对热泵机组性能系数的影响高于对系统性能系数的影响;对于太阳能、地热能和电能对热负荷的贡献比例而言,蒸发器入口温度越高,太阳能对热负荷的贡献比例越大,地热能的贡献比例越小,而电能的贡献比例变化不明显.

Research on heating characteristics of a solar assisted ground source heat pump system under different dynamic loads

A dynamic simulation model of the solar assisted ground source heat pump system (SAGSHPS) is established. Based on the conditions of the intermittent load 1(heating demand appearing from 8:00 to 20:00), the intermittent load 2 (heating demand appearing from 18:00 to 7:00) and the continuous load (heating demand appearing all day), the hourly dynamic simulation of the heating process for the SAGSHPS is carried out during heating season in Dalian. The operation characteristics of the SAGSHPS are analyzed under these three typical dynamic loads. The results indicate that the heating operation modes of the SAGSHPS are different in the coldest day in winter under different loads. Under the intermittent load 1, the SAGSHPS alternatively operates with the ground source heat pump (GSHP) and solar heat pump (SHP). However, the mainly heating operating mode is the GSHP under the intermittent load 2, which is supplemented by the SHP only in the early night. Under the continuous load, the SHP heats space during the day and the GSHP operates at night. The impact of the evaporator inlet temperature on the coefficient of performance for heat pump is higher than that of on the coefficient of performance for the system during the entire heating season. For the ratio of solar energy, geothermal energy and electric energy to the heating load, the higher the evaporator inlet temperature is, the greater the ratio of solar energy to heating load is, while the lower the ratio of geothermal energy to heating load is. At the same time, the change of the ratio of electric energy to heating load with the evaporator inlet temperature is not obvious.