相变能量桩段模型传热模拟

针对能量桩体材料普通混凝土储热性能差问题,将相变材料引入普通混凝土中构建相变能量桩。利用简化能量桩段有限元数值模型模拟了普通能量桩与相变能量桩的传热过程,对比分析了两者的传热差异;并通过添加不同质量分数相变材料,研究了添加量对能量桩桩体、桩周土传热的影响。研究结果表明:在换热管吸放热工况下,相变材料的添加可在相变温度区间内明显延缓桩体升降温速度;相变材料的添加量越多,升降温延缓作用越明显;能量桩中添加相变材料只对桩体的传热影响显著,对桩周土的温度场影响较小。

Heat Transfer Simulation of Phase Change Energy Pile

Aiming at the problem of poor heat storage performance of ordinary concrete as energy pile materials, phase change materials were introduced into ordinary concrete to construct phase change energy piles. The heat transfer process of ordinary energy piles and phase change energy piles was simulated by the finite element numerical model on simplified energy piles. The difference of heat transfer between the two energy piles was compared and analyzed. The effects of the mixing content on the heat transfer of the energy pile and the soil around the pile were studied by adding different mass fractions of phase change materials. It is found that the addition of phase change material can significantly delay the temperature rising and decreasing of the pile in the phase change range when the heat exchange tube absorbs or releases heat. The more the phase change material is added, the obvious the delay effect of temperature rising and decreasing. The phase change material added to the energy pile only has a significant effect on the heat transfer of the pile, while has little effect on the temperature field of the soil around the pile.