地下换热管热变形引起的管-土间隙

Pipe-soil gap induced by thermal deformation of ground heat exchange pipe

通过建立换热管典型平面弯曲态几何模型及本构模型分析不同温度地下换热管传热过程中管土结构热变形特征,着重研究典型初始弯曲管体热变形对管-土间隙演变发展的影响。研究表明,通常换热管弯曲凹侧出现较大间隙,其间隙分布占管体周边一半左右;当换热管初始弯曲较小或基本无弯曲时,其较大间隙出现在U形换热管的两管间对应区域,管-土间隙量随初始弯曲程度的增加而增加。

The geometrical model of typical plane bending state of heat exchange pipe and the constitutive model are established. Then the thermal deformation characteristics of pipe-soil structure in heat transfer at different temperatures are analyzed. It is focused on the influence of typical initial thermal deformation of bending pipe on the development of pipe-soil gap evolution. Results show that larger pipe-soil gap appears in the concave side of the bending heat exchange pip. The gap distribution around the buried pipe is about half of the pipe perimeter. The larger gap of smaller bending deflection or no bending heat exchange pipe mainly appears at the corresponding area between two pipes of U- type heat exchange pipe. The magnitude of pipe-soil gap increases with the bending degree of the heat exchange pipe.