Abstract:

Taking geometric symmetry and the approximately same periodic variation of the temperature field around partial buried pipes into account, simplified analysis of heat transfer for vertical multi-boreholes ground heat exchangers was carried out. On the basis of finite line heat source model, an example of non-seepage matrix layout of vertical multi-boreholes ground heat exchangers was selected to simplify the analysis of heat transfer. For the purpose of simplification on heat transfer analysis, representative buried pipe matrix (RBPM) was proposed in place of the original vertical multi-boreholes ground heat exchangers. Through the analysis on heat transfer of a single buried pipe and RBMP, it was considered that the heat transfer of RBPM can be determined according to the influencing radius of heat transfer of a single buried pipe under the same conditions of the geological conditions, geometry parameters, loads and operation conditions. Thermal conductivity of soil affects the scale of RBPM. Under the conditions in this article, the larger thermal conductivity of the soil is, the smaller scale of RBPM is.

Key words: ground heat exchangers, heat transfer, model, simulation, simplify

摘要：

提出利用几何对称性和部分埋管周围温度场呈近似相同周期性变化的特点,对集群竖埋管地热换热器传热分析进行简化的方法。在有限长线热源模型基础上,以无渗流矩阵形式布置的集群竖埋管地热换热器为例,利用该方法进行简化分析,提出采用代表性埋管矩阵代替原集群埋管地热换热器进行传热分析。结合代表性埋管矩阵和相应工况下的单根埋管传热进行分析,认为可以通过单根埋管的传热影响半径,确定地质条件、埋管几何参数、负荷及运行条件等相同情况下大型集群埋管换热器的代表性埋管矩阵。土壤热导率大小影响代表性埋管矩阵的规模,本文条件下土壤热导率越大,确定的代表性埋管矩阵越小。

关键词: 地热换热器, 传热, 模型, 模拟, 简化