摘要
为降低传统圆柱型螺旋能量桩(CyHEP)的轴向与径向热干扰程度以提高传热效率,提出一种新型的圆台螺旋能量桩(CoHEP)。采用格林函数法推导得出CoHEP能够分析圆台型螺旋能源桩换热能力的"影响系数"的概念。研究表明,在相同换热管长的情况下的CoHEP换热性能优于CyHEP,圆锥角越大,"影响系数"越大,强化换热效果越好。在圆锥角相同时,螺距越小,"影响系数"越大,圆台型螺旋能源桩对小螺距情况下的强化传热效果更加显著。
In order to weaken the thermal interference in the generatrix and radial directions,a novel truncated cone helix energy pile is presented and an analytical solution model for the novel energy pile is proposed based on Green's function. The entire average non-dimensional temperature on the pile wall is calculated and the parameter of influence coefficient is employed to analyze the heat transfer performance of helix energy pile. It is indicated that the heat transfer performance of CoHEP is better than that of CyHEP. Higher influence coefficient can be obtained by setting a bigger cone angle and the enhancement of heat transfer is more remarkable with a smaller coils pitch for CoHEP.
引文
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