有均匀渗流的介质中螺旋埋管的传热分析

HEAT TRANSFER OF SPIRAL COILS BURIED IN MEDIUM WITH UNIFORM GROUNDWATER ADVECTION

以埋设在均匀渗流介质中的螺旋埋管为研究对象,结合地源热泵工程应用背景,将地下螺旋埋管简化为连续的螺旋线热源,通过移动线热源理论与格林函数法,建立二维和三维非稳态的导热与对流联合作用的渗流传热问题的传热模型;求得无限长及有限长螺旋热源形态下渗流问题的温度响应的解析解。通过与纯导热模型的对比可知,地下水渗流会在一定程度上影响地下温度场的分布及传热达到稳态所需的时间。指出渗流速度是体现地下水流动对换热过程影响程度的重要参数,且渗流对整个螺旋管群的换热影响也被分析讨论。

Taking the engineering applications of the ground source heat pump and spiral coils buried in the ground with uniform advection of groundwater as the research object, the buried spiral coils were simplified to continuous spiral heat sources. By means of Green Function and moving heat source, the combined conductive and advective heat transfer models （2-D and 3-D unsteady models） were developed. The analytical solutions of temperature response for infinite and finite length spiral coil heat resource advection of the groundwater were obtained. Compared with the pure heat conduction models, the advection of groundwater could affect the distribution of ground temperature field and the time for heat transfer to reach steady state in some degree. The results indicate that the advection velocity of groundwater is the significant parameter embodying the influence degree of the groundwater advection on heat transfer process, and the effect of advection on spiral coils group has been investigated.