传热过程

• Compared to heat transfer in the external region of borehole , mass and heat capacity of materials inside the borehole are insignificant and negligible . thus , heat transfer inside the borehole is approximated as steady - state heat transfer except for analyses of short times ( a few hours )
  与钻孔周围区域传热过程相比，由于钻孔内材料的热容量较小，因此除了讨论短时间(数小时)的瞬变传热问题以外，可以忽略钻孔内材料的热容量，把该部分的传热近似作为稳态传热处理。