Investigation of Solar Absorption Coefficient of the External Walls of Residential Building on Energy Consumption Reduction

Today's energy needs are increasing very fast and this is while the energy resources are very limit. In this paper by using numerical methods and investigation absorption coefficient of different colors, the most appropriate color to reduce energy consumption in all seasons has been selected for external wall of a building in Mashhad. Modeling of building has been done and meshed by using Gambit software as a three dimensions model. The simulation of falling solar radiation to building which is the main objective of this study, has been done by Fluent software based on building’s location and in turbulent flow. The results of this research indicate that by selecting the most appropriate color, in total during of the year by 1.5°C temperature decrease in warm days and about 1°C increase in cold days, we have significantly reduce energy consumption in electricity and gas. Finally according to the results of this research and by investigating absorption coefficient of different colors, gray color has been chosen as the most suitable criteria in order to reduce building energy consumption.