Design parameters for a solar heating system with an underground cylindrical tank

We have performed a theoretical analysis of a solar heating system with an underground cylindrical tank. A two-dimensional ground-temperature distribution is used around the tank. Heat-transfer problems are solved by application of complex, finite Fourier-transform technique and a finite difference method. A 25- and a 100-house community are considered for the performance calculation. The effects of collector area, tank volume, number of houses, and depth of the tank have been investigated for Istanbul (40°N). Isotherms of the ground around the tank are illustrated in graphical form.