270-垂直地埋管热相似试验台原理及试验验证.pdfVIP

垂直地埋管热相似试验台原理及试验验证 重庆大学城市建设与环境工程学院 彭远玲 李文欣 韦科娟 谢烨 王勇 摘要：以考虑岩土竖向分层的垂直地埋管换热器传热模型为基础，通过热相似原理对该 传热模型进行相似转换，得到了几何、时间、流速等相似倍数的关系。以某工程为例，基于 相似准则搭建了尺寸为6.25m×1m×1.5m 的垂直单U 地埋管相似模型试验台。通过该试验台 地埋管运行 24h （相当于原型运行 64 天）的测试数据，对已建的三维数值模型 （相似模型 和原型）计算结果进行验证。结果表明，地埋管出口温度平均相对误差为 1%，进出口温差 平均相对误差为8%，土壤温度相对误差为3%。该试验台实现了以较小的成本和可控短期运 行时间对复杂工况下地埋管长期换热规律的研究。 关键词：垂直地埋管 岩土分层 传热模型 相似试验台 数值模拟 Principle and test verification of a similar experiment system for vertical ground heat exchangers College of Urban Construction and Environmental Engineering, Chongqing University Peng Yuanling, Li Wenxin, Wei Kejuan, Xie Ye and Wang Yong Abstract:Based on the heat transfer model of vertical ground heat exchanger considering soil vertical stratification, the heat transfer model was similarly converted by the thermal similarity principle, and similarity ratios such as flow velocity, geometry and time were obtained. Based on the similarity criteria, a vertical single U pipe similarity model experiment system with dimensions of 6.25m×1m×1.5m was built. Through the experiment system running 24h (equivalent to 64 days of prototype operation) test data, the calculated results of the three-dimensional numerical model (similar model and prototype model) have been verified. The results show that the average relative error of the outlet temperature of the buried pipe is 1%, the average relative error of the temperature difference between the inlet and outlet is 8%, and the relative error of the soil temperature is 3%.The similar experiment system has realized the study of the long-term heat transfer characteristics of buried pipes under complex conditions with relatively low costs and controlled short-term operating time. Keywords:vertical ground heat exchanger, layered soil, heat transfer model, similar experiment system, numerical simulation 0 引言 地源热泵作为一种可再生能源技术，近年来被广泛的应用和发展，其中以垂直埋管式地 源热泵系统应用最为广泛。垂直埋管式地源热泵系统的运行效果直接受到地埋管