土壤导热系数对井下换热性能的影响分析

Influence of soil thermal conductivity on underground heat transfer performance

影响井下换热的因素有多种,其中土壤导热系数是最主要的因素之一。以深度为2 200 m的中深层地热井为例,采用闭式循环"取热不取水"方式进行取热,用OpenGeoSys软件进行模拟计算。采用的方法为单一变量法,在其他因素保持不变的情况下,计算土壤导热系数对井下换热量的影响。结果表明:在供暖季的采暖初期,进出口温度下降较快,随着时间的增加,进出口温度趋于稳定;当土壤导热系数为发生变化时,进出口温度有所变化,但进出口温度变化趋势基本一致;随着土壤导热系数的增加,进出口温度略有提高。

There are many factors affecting heat transfer in underground mine, among which soil thermal conductivity is one of the most important factors. Taking the deep geothermal well with depth of 2 200 meters as an example, the closed cycle "heat without water" method is used for heat extraction, and OpenGeoSys software is used for simulation calculation. The single variable method is used to calculate the influence of soil thermal conductivity on underground heat transfer while other factors remain unchanged. The results show that: in the early warm period of heating season, the inlet and outlet temperature decreases rapidly, and with the increase of time, the inlet and outlet temperature tends to be stable;when the soil thermal conductivity changes, the inlet and outlet temperature changes, but the change trend is basically the same;with the increase of soil thermal conductivity, the import and export temperature slightly increases.