Earth-to-air heat exchangers cooling evaluation for different climates of Iran

Abstract

Earth-pipe-air heat exchangers (EPAHEs) are viable alternatives or supplements to conventional central heating or cooling systems. In present study, to reduce the cooling load of a sample residential building; usage and potential energy conservation of a four-pipe EPAHE were studied for different climates of Iran. The evaluation of the EPAHE was based on a three-dimensional transient computational model and validated by experimental data of another research. For this purpose four cities of Iran, by different climates (Temperate, Steppe, Desert, and Snow) were selected according to climate classification map of Wladimir Köppen, and the inlet/outlet temperature of working fluid (air) for each pipe, the monthly average energy conservation, and the maximum cooling load of the building with and without the EPAHE for these cities were compared in July.As a result, the average energy conservation by the EPAHE is significantly differentin selected cities with different climates. The energy conservation shows better when the city soil, is silt in comparison with loam and clay. Also in some cases, using of EPAHE shows a negative effect on the air-conditioning of buildings. The model was developed by the FLUENT simulation program.