An analytical method to evaluate the impact of vertical part of an earth-air heat exchanger on the whole system

Abstract

Abstract This paper presents a simplified analytical model within numerical results to determine the thermal balance of Earth-Air Heat Exchanger (EAHE). The EAHE is a device which uses the principle of soil thermal inertia used for ventilation in buildings. It has three sections: a vertical section at the entrance, an horizontal section in the area of soil thermal inertia and a vertical section at the exit, also considered as area in soil thermal inertia. The assessment for the heat algebrical gain at the vertical section of air entrance in the EAHE is established. In this study, the initial conditions of the problem are obtained and the temperature equation specified model is solved analytically, by considering that the vertical part of an EAHE or a vertical EAHE is under periodic fluctuations in both ambient air temperature and soil temperature. The model can predict the air temperature variation along vertical and horizontal section of the tube for any hour of the day and can be used for a vertical EAHE. It can also determine the daily or annualy mean and amplitude of the total cooling or heating effect of the tube. Numerical results are graphically presented, discussed and compared to experimental datas.