Experimental And Numerical Study of An Earth-To-Air Heat Exchanger for Buildings Air Refreshment in Marrakech

Abstract

This paper deals with a numerical and experimental study of the thermal performances of an Earth-to-Air Heat Exchanger (EAHX) connected to a country house in Marrakech (31°37' N latitude and 8°2' W longitude). The EAHX consists of three parallel PVC pipes of 72 m length each and 15 cm inside diameter, buried at 2.2-3.2 m depth. Each pipe is equipped with a fan, which push treated air into the house. The experimental study consists of the monitoring of one pipe via measurement of air temperature and humidity along the pipe as well as at its entrance and exit to the house. Dynamic simulations were carried out using TRNSYS software (Type 460). The model was validated through 38 days monitoring of the EAHX. Numerical and experimental results are in good agreement. Air temperatures inside the EAHX reached a quasi-constant value of 22°C at a pipe length of 72 m and a depth of 3.2 m. This corresponds to air temperature reduction of 19.8°C.