Hygrothermal study of dwelling submitted to passive cooling

Abstract

A significant portion of energy consumed in buildings is due to energy usage by heating, ventilation, and air conditioning systems. Free cooling is a good option for energy savings in the systems. In recent years, scientists, engineers, and architects designed successful and innovative buildings which use passive cooling techniques, such as natural ventilation. The house studied in the present work, is a pilot project undertaken jointly by the Centre for Development of Renewable Energies (CDER) and the National Centre for Studies and Research of the integrated building (CNERIB) in the framework of the MED-ENEC project (Mediterranean Energy Efficiency in Construction structure). The house under consideration has a surface area of 65 m2 and is located in the region of Algiers which characterized by a Mediterranean climate with relatively mild winters and a hot and humid summer. The aim of this work is to study the thermal comfort inside the house in summer without air conditioning systems, only ventilation is considered. The aim of this work is to study the effect of natural ventilation on both thermal and hygrometric comfort inside the house during the summer period. Numerical simulation is made using the TRNSYS software and the results obtained are in good agreement with measured values. The prototype home is designed in a way that natural ventilation allows thermal comfort which induced energy saving from air conditioning. The mean temperature measured in the interior of the house is 26 °C. The relative humidity reaches about 70% in August. Thermal comfort is related to relative humidity that are the essential parameters of the feeling of comfort. Humidity is an important parameter in thermal comfort, it is why we can conclude that we have reached a relatively good hygrothermal comfort.