Absorption of solar energy in a room

Abstract

The purpose of this study is to develop an analysis that allows an examination of the spatial distribution of the absorbed solar energy for a room. The room is composed of several areas that consist of an exterior window where solar beam and diffuse energies originate, an interior window, a door, and six opaque areas. Each area is subdivided into a number of discrete surfaces and an analysis based on the radiosity-irradiation method is used to determine the absorbed solar energy for each surface. A geometrically-based method is used to describe the location and magnitude of the directly incident solar beam energy for each surface. The influence of the number of discrete surfaces on the findings is examined. The results show that a grid pattern that produces discrete surfaces having dimensions of less than 0.3 m yields accurate results. Results are reported for different orientations of the room. As expected, the absorbed solar energy is high in regions where the solar beam energy irradiates a surface. The spatial distribution of the absorbed solar energy does vary significantly over the areas of the room. Measured solar energy values are used to compute the absorbed solar energy as a function of time of day. The movement of the energy across the surfaces of the room creates a time-varying value for the absorbed solar energy. Numerical values for the ratio of the absorbed solar energy for each area to the available solar energy from the exterior window are supplied.