Extensive Parametric Study of Cooling Performance of an Earth-to-Air Heat Exchanger in Hot Semi-Arid Climate

This work aims to provide some design guidelines for Earth-to-air heat exchangers (EAHX) in hot semi-arid climates. An extensive parametric study in the context of the soil properties and hot climate of Marrakech (Morocco) is carried out considering all the EAHX design parameters that are the EAHX pipe length, number, diameter, spacing, burying depth, and the airflow velocity. More than 400 of the EAHX parameters' combinations are studied by carrying out more than 400 dynamic simulations using the well-validated TYPE 460 of TRNSYS. Thermal performances of the EAHX are assessed for the air cooling of the buildings by means of "the maximum cooling efficiency," which is related to the blown air temperature into the building. The results are presented in terms of charts of the cooling efficiency for two parameters at the same time, while the others were set to their reference values. Useful design guidelines, to get air cooled at a set point temperature, are derived.