Numerical Investigation of Thermal Comfort and Air Quality for a Single-Sided Naturally Ventilated Office Room

Document Type : Research Paper

Authors

1 Department of Mechanical Engineering, University of Mohaghegh Ardabili, Ardabil, Iran

2 Department of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran

Abstract

The aim of this research is to investigate the effect of different parameters on thermal comfort of occupants in an office room equipped with single-sided natural ventilation. A three dimensional numerical model was implemented to predict temperature and velocity distribution in the space using Ansys Airpak software. Then, the temperature and velocity distribution obtained from the numerical solution is coupled with the standard thermal comfort indices (PMV, PPD) and local discomfort indices (DR and PD) in order to evaluate the thermal sensation of occupants. The results shows that the outside temperature between 18  and 20  is the best temperature range in establishing comfort conditions for all occupants and the PMV value is between -0.4 and 0.6, which is consistent with the determined criteria by ISO 7730. As the temperature increases, the mean age of air increases, but thremal discomfort due to draught (DR) decreases. By increasing the wind velocity and dimensions of the openings, the values ​​of PMV and PPD decrease and become closer to the permissible range of thermal comfort. The mean age of air decreases with the increase of the wind velocity and the dimensions of the openings and reaches its lowest value at a speed of 7 m/s, but DR remains constant with the change of wind velocity. According to the results, installing two openings has a better performance in establishing thermal comfort conditions than installing a single opening.

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