Numerical Investigation of Horizontal Ground Coupled Heat Exchanger

Nowadays, the improvement of the quality of life has contributed to a growing demand for AC systems in buildings. Among the technologies used in AC equipment, the ground-coupled heat exchangers (GCHE) are drawing more and more interest because of its environmental characteristics compared to conventional heat generation or dissipation systems. A typical GCHE consist on a set of pipes buried vertically or horizontally in the ground and coupled to a heat pump (HP). In this paper, the study was focused on a horizontal configuration based on heat exchanger pipes laid out concentrically. An unsteady quasi three-dimensional numerical simulation was carried out for cooling purposes in continuous and cyclic operating mode. The variation of the climatic conditions in transient simulation was taken into account by modeling the air and ground temperature using a simple harmonic function. The influences of thermal conductivities and geometrical parameters on the heat exchanger efficiency have been studied.