导热型地温梯度场内的U型管式井下换热器

建立了一个描述“Ｕ”型管式地热井下换热器在导热型地温梯度内热性能的数学模型。该模型考虑了地下岩层的温度分布及岩层与其下面对流层的对流换热对“Ｕ”型管式地热井下换热器热性能的影响，并对井下换热器流体进口参数的变化，岩层热物性及温度剖面变化对热输出的影响进行了计算。

U SHAPE DOWNHOLE HEAT EXCHANGER IN A REGION WITH CONDUCTIVE GRADIENT

A pure conduction model is used for modelling the performance of "U"shape downhole heat exchangers (DHEs).The common formation temperature feature around a well.especially for a shallow well where a DHE rig is installed. is that it has a conductive section at the top and a convective section at the bottom.The aim of this paper is to see how much heat can be extracted for a "U" shape DHE operating atpure conduction state and to have a deep understanding about the mechanism of heat transfer in the wells.The effects of various parameters on heat output are also analysed.