基于穷举搜索法的地下岩土热物性参数分析  

Exhaustive search method to determine the underground soil thermal properties

作　　者：吴迪[1] 于明志[1,2] 

机构地区：[1]山东建筑大学热能工程学院,山东济南250101 [2]山东建筑大学可再生能源建筑利用技术教育部重点实验室,山东济南250101

出　　处：《山东建筑大学学报》2016年第4期358-365,共8页Journal of Shandong Jianzhu University

基　　金：国家自然科学基金项目(51176104)

摘　　要：地下岩土热物性参数测量的准确性影响地埋管换热器设计的合理性,进而影响地源热泵系统初投资和运行性能。文章利用穷举搜索法结合参数估计方法对热物性参数组合值进行全域搜索,并获得地埋管循环水温度测量值与模型计算值之间的方差和最小值,通过模拟验证该方法计算结果的可靠性,并与优化方法计算结果对比分析。结果表明:穷举搜索法可以确定较为准确的热物性参数值;优化方法仅确定的导热系数具有可靠性,相对误差小于1%,但钻孔内热阻和容积比热计算结果相对误差可达到70%以上,可信度较差;在实际工程中,优化方法所得的导热系数的值与穷举搜索法所得的值接近,但钻孔内热阻相对偏差最高可达41.42%,相对应的容积比热相对偏差最高为67.98%。rationality The accuracy of measured underground soil thermal properties affects the designing ofground heat exchangers and then influences the investment and operation performance of the ground source heat pump systems. Together with the parameter estimation method, the exhaustive search method is used to determine the underground soil thermal properties by thoroughly searching the combinations of different soil thermal properties. The minimum variance between the measured and calculated circulating water temperature is to be obtained. However, the soil thermal parameters corresponds to the minimum variance are the results. After verifying the reliability verification of the exhaustive search method by simulation, the results are compared with those obtained by the optimization method. The result demonstrate that the exhaustive search method can obtain the more accurate group of soil thermal parameters. As comparison, though the optimization method can find the underground thermal conductivity with high credibility, the borehole thermal resistance and volumetric heat capacity are poor credibility. The relative error of underground thermal conductivity is less than 1%, but that of the borehole thermal resistance and volumetric heat capacity are more than 70%. The results of thermal conductivity calculated by the optimization method range respectively from 2.00 to 2.02 W/（m·K） and from 1.00 to 1.02 W/（m·K） in these two projects. These results are close to the corresponding results of the exhaustive search method, 2.01 W/（ m·K） and 1.01 W/（ m·K）. However, the borehole thermal resistance＇ s highest relative deviation can be up to 41.42%. And corresponding volumetric heat capacity＇ s highest relative deviation can reach 67.98%.

关 键 词：岩土 热物性参数 穷举搜索法 优化方法 

分 类 号：TU201.5[建筑科学—建筑设计及理论]