地热井U型管周围土壤温度场的ANSYS模拟

摘要

Heat transfer between pipe heat exchanger and rock is a complex process, and finite element simulation method is an effective method to analyze this process.Through the comparative analysis to two-dimensional single well model, the authors establish two-dimensional multi-wells heat transfer model, there are nine heat storage wells with interval of 4 meters for each.The heat transfer process of this model follows the classic heat transfer theory.According to the ANSYS grid division principle, solution region is divided into the cells with the maximum edge length of 0.1 m and the smallest edge length of 0.01 m.Buried pipe is applied heat load density inside, and applied ground temperature boundary load outside, and after 72 hours simulation of heat storage process, accurate changing regularity of temperature field of rocks around multi-wells is obtained.The highest temperature is 40.263℃, the lowest is 10℃, and the influence radius is 1.4 m.The increased ampltude of temperature decreases, and the migration patterns of temperature and heat are obtained.The simulation results match well with the actual measurements.%埋管换热器和岩土的传热是个复杂过程,利用有限元仿真分析两者的传热过程是有效的办法.通过与单井二维模型的对比分析,建立二维群井传热模型,模型为9口间距为4 m的储热井,模型传热过程遵循经典传热理论.按照ANSYS网格划分原则,将求解区域划分为最大边长0.1 m,最小边长0.01 m的单元.在地埋管内侧加载热流密度,外边界加载地温边界条件,经过模拟72 h的储热过程,精确得出群井周围岩土体的温度场变化规律,求解区域最高温度为40.263℃,最低温度为10℃,影响半径约1.4 m,温度的升高幅度会减缓,并得到了温度及热量迁徙的规律.模拟结果与实际测量结果相符.