The 2-D thermal analysis of the coil ground heat exchanger inside piles

In view of its engineering applications of the coil ground heat exchanger inside foundation piles,a solid cylindrical heat source model is proposed to describe the heat transfer process of the spiral coil ground heat exchangers.By means of the green function method and the virtual heat source approach analytical solutions have been derived,applicable for temperature distribution of the one-or two-dimensional cylindrical heat source models with infinite and finite length.The geometrical and physical parameters which impact on this heat transfer process have been analyzed and discussed accordingly.Besides,two representative temperatures,i.e.integral average temperature and mid-point temperature on cylindrical surface,are also calculated and discussed.