摘要
针对西安地区的地质状况及气候特点,建立了管内流体、地埋管换热器及周围土壤耦合传热模型,模拟了U型管内流体流动和传热、U型管与回填材料及土壤的传热。建立了连续模型和间歇模型,通过模拟分析得出结论:在西安地区应用土壤源热泵系统,热泵系统连续运行时间不能超过一定的时间(夏季为18h,冬季为7h),超出此时间后,由于换热器周围土壤中热量(或冷量)累积,使得换热环境恶化,换热器与周边土壤的换热量不断下降,导致热泵机组在不利工况下运行,长此以往,当U型管出口流体温度上升(下降到)到机组的保护温度时,压缩机将停止运行。与连续运行工况相比,在西安地区采用间歇运行工况时,地下换热器周围土壤可以得到一定程度的恢复,且间歇时间越长,恢复的程度越好。
In the conditions of the geological conditions and climate characteristics of Xi＇an, we established a fluid pipe, heat exchanger and the surrounding ground heat transfer model, simulated the U- tube fluid flow and heat transfer, U- tube, the backfill material and soil heat transfer. In the paper, a continuous model and intermittent model were established respectively, through the simulation the author drew the following conclusion： when the ground source heat pump system is used in Xi＇an, continuous runtime cannot exceed a certain amount of time（ 18 hours in summer and 7 hours in winter）, then, as the heat accumulated in soil around the heat exchanger, environmental degradation makes thermal conduction to have a downward trend between heat exchanger and the surrounding soft, which resulted in heat pump nmning in adverse conditions, and if it lasts a long time, the condensation temperature of heat pump （or evaporation temperature） is too high （low）, once it reaches the thermal protection level, the compress will step running. Compared with a con- tinuous model, when intermittent model was used, the underground soil around heat exchanger can have a certain degree of recovery, and the longer interval, the better the degree of recovery.
出处
《河南城建学院学报》
CAS
2009年第3期31-35,共5页
Journal of Henan University of Urban Construction
关键词
热泵
数值模拟
传热
连续模型
间隙模型
heat pump
numerical simulation
heat transfer
continuous model
intermittent model
