Study of the ground water permeation s influence on energy pile heat exchange in porous medium soil

Energy pile heat storage technology is a typical soil source heat pump system, and features and parameters of soil have great influence on the heat storage of energy pile. Ground water permeation will take heat in soil away directly and if the permeation speed is too fast, the heat storage system of the energy pile even cannot store heat. In order to guarantee that the heat storage system of the energy pile can function well in practical working conditions, it is necessary to do further quantitative study of the ground water permeation’s influence on soil source heat pump. This study focuses on soil permeation’s influence on energy pile heat exchange through establishing the energy pile heat storage model and finds that when the permeation speed is less than 3×10-7m/s, it is the desirable heat storage condition; when the permeation speed is more than 1×10-6m/s, the energy pile heat storage system cannot store heat at all.