A parametric analysis of the cooling performance of vertical earth-air heat exchanger in a subtropical climate

Nearly 30% of global energy is consumed in buildings for heating and cooling. Many researches have been undertaken at finding novel techniques to reduce buildings’ energy consumption without using any conventional mechanical devices. Earth-air heat exchanger (EAHE) is such a passive cooling technique that is seen to significantly reduce energy consumption. This paper investigates the cooling performance of a vertical EAHE for a subtropical climatic zone through a parametric analysis. A thermal transient model for the vertical EAHE has been developed using ANSYS Fluent to analyze the parametric study. The influence of the key parameters: air velocity, thickness, diameter, depth, length, and material of the pipes on the EAHE cooling performance has been conducted and presented here. This parametric study is viewed as new in a subtropical climate since no such study is found in the literature and its outcome will provide a deeper understanding of the passive cooling system. The cooling performance is considerably affected by pipe diameter, air velocity, and pipe length while no noticeable impact is found for pipe material. The optimal performance contributed to reducing the outlet air temperature up to 8.21 °C.