Abstract
It has been recently recognized how important it is to improve living environment in a building and save fossil energy by utilizing natural energy resources and natural environment. Since we need both heating and cooling in this country, it is necessary to investigate the possibility of passive cooling in summer as well as passive heating in winter. From this point of view, this paper takes up evaporative cooling by means of roof spraying as a technique of passive cooling, and passive cooling effect is studied on a model building roof sprayed with water and naturally ventilated by temperature differences and wind forces. First, this paper describes the calculation method of room temperature, humidity and air pressure in a building, which is roof sprayed and naturally ventilated by temperature differences and wind forces. Secondly, room temperature, humidity and air pressure are simulated for a model factory according to the above-mentioned calculation method, varying the conditions of heat insulation grade and the rate of internal heat generation, with the aid of meteorological data of the Tokyo area in summer. The seasonal frequency of room temperature, humidity and environmental temperature is analyzed by comparing it with the results obtained from "without roof spraying", followed by a discussion on combined passive cooling effects of roof spraying and natural ventilation as well as improvements on the inner thermal environment of the building.
