基于遗传算法的岩土及填料热物性参数评估

岩土及填料的热物性参数可直接影响地埋管换热器的性能设计.针对现场热响应测试中填料热物性参数需要预先测量，而无法通过计算直接评估的难题，在无限长线热源模型及管壁热阻修正复合介质线热源模型的基础上，应用遗传算法对岩土及填料的热物性参数同时进行评估，并结合热响应测试实验，验证了该方法的准确性.钻孔热阻、岩土导热系数和填料导热系数的评估值与实测值的相对误差分别为3.47%，1.42%和4.93%.2种模型计算所得流体平均温度与实测值的均方根误差分别为0.050 5 ℃和0.172 ℃.研究结果对地埋管换热器的设计具有重要参考价值.
The parameters for thermal properties of ground and grout have directly effect on the performance of ground heat exchanger (GHE). For the problem that grout thermal properties of in-situ thermal response test (TRT) need to be measured in advance and cannot be evaluated directly by calculation, this paper applied genetic algorithm to evaluate the parameters of ground and grout thermal properties simultaneously on the basis of infinite line source (ILS) model and composite media line source (CMLS) model with wall thermal resistance correction. The method was validated by in situ TRT. Compared with the measured values, the calculation relative error of borehole thermal resistance, ground thermal conductivity and diffusivity was 3.47%, 1.42% and 4.93%, respectively. The root mean square error (RMSE) of the calculated average temperature by these two models and the measured value is 0.0505 and 0.172 ℃, respectively. The results provide important reference for GHE design.