RETROREFLECTIVE PROPERTIES CALCULATING METHOD BASED ON GEOMETRICAL-OPTICS ANALYSIS

Performance evaluation of solar retroreflectors

Abstract

If the albedo on the surface of a building is raised, it is expected that the effect of reducing the thermal load of a building, and also the depression effect of urban heat island phenomenon. If the retroreflectors are used in order to reflect solar radiation, it can reflect towards the incidence direction using the directivity of direct-beam solar radiation, therefore effective reflection may be able to expect. In order to evaluate the reflection performance to the direct-beam solar radiation, the optical properties of the retroreflectors are analyzed and the simple expressions which evaluates reflection performance are drawn. In this paper, the target retroreflectors are two sorts of a three-mirror type and a four-mirror type of corner reflectors.