Effect of the Window Design Features on Natural Ventilation

Abstract

Abstract Air vents and windows significantly affect the temperature, humidity, air distribution and air quality of domestic buildings. It is notable that, in most of the modern residential building designs in Sri Lanka, the air vents are not available while, air vents were a popular feature in traditional buildings. This paper investigates the effect of air vents on the distribution of indoor temperature and air velocity of a domestic unit. This was carried out by simulations of a living room for four different window and air vent arrangements. The window comprises of two features: one which is closable and typically covers 80% of the area, while the other is a lattice which is always open. The latter is located on top of the former. The air vent is located at a distance above the window. The four designs which were compared are: 1. without air vents, (a) closed and (b) open window and 2. with air vents, (a) closed and (b) open window. The simulations revealed that introducing the air vents increases vorticity of indoor air while, creating a better temperature distribution. This serves as a factor to increase indoor thermal comfort. Further simulations were carried out to find the optimum shape of the air vent and number of air vents. Through which, a relationship is to be formulated between the window design parameters towards establishing thermal comfort in domestic buildings in tropics.KeywordsAir ventsNatural ventilationTraditional buildingsWindow design