Análise da influência das propriedades termofísicas do solo na troca de calor realizada por um sistema de climatização passivo

Abstract

One way to reduce energy consumption in buildings is by increasing the efficiency of HVAC equipment. There are several ways to accomplish this, usually through new, often more expensive, technologies. However, there are sustainable alternatives to energy saving without this being a high investment. One such alternative would be the exchange of heating, ventilation and air conditioning (HVAC) systems for a ground-to-air heat exchanger or EATHE (Earth Air Tunnel Heat Exchanger). As a result of its high thermal inertia, the soil can work as a thermal reservoir, heating or cooling the air from inside the building, depending on weather conditions. Thus, in this work, it was verified the thermal performance of an EATHE numerically, through the computational fluid dynamics (CFD). Initially, the effect of air velocity on thermal exchange was analyzed, and then the effect of thermophysical properties of two different types of soils was verified. It was found that saturated soils, with higher thermal conductivity, exchanged heat faster. and lower pipe outlet temperatures compared to simulations using dry soils regardless of inlet velocities or flow times.