EVALUATION OF CORRECTION FACTOR IN QUASI-STEADY STATE METHOD FOR ASSESSMENT OF OPERATIONAL COOLING - IMPACT OF ORIENTATION ON WINDOW, WALL AND FLOOR AREA

摘要

Building orientation is a significant passive design consideration in the pre-design stage of a building, mainly in tropical countries where absorption of the radiation of the sun plays an important role in determining the cooling energy requirements of any building. This paper describes an investigation into the deviation of the assessment of Operational Cooling Energy requirements in low-rise multi-storeyed apartments, having a floor area less than 500 sq m, in terms of Dynamic calculation of cooling energy loads and the same in Quasi-Steady State (QSS) method, with the effect of orientation of the window to wail area and window to floor area ratio. The authors evolved a methodology of quantifying a modification constant that, when added to the utilisation factor in QSS method, would bring down the gap between the cooling energy calculated through Quasi-Steady State at pre-design stage with the same in dynamic calculations after the completion of the design, thus providing a tool for decision making for selection of an appropriate design alternative in early design.