AN EXPERIMENTAL STUDY ON THE SHADING COEFFICIENT OF SUNLIT WINDOWS WITH VENETIAN ROOM BLINDS

摘要

In order to evaluate solar heat gain through windows with internal shading devices, I developed an experimental apparatus which consists of two boxes. One box is holds a clear glass pane with internal shading devices, for example, a conventional ivory white blind. The other box holds a clear glass pane. All walls of the boxes, except the openings, are composed of thermal insulating materials. The values of shading coefficient (SC) of thirty conventional venetian blinds were measured with the experimental apparatus. For example, SC of a conventional ivory white blind set at 45-deg slat angle was 0.58 and that of a medium cream_colored blind was 0.68. And the measured values of Sc were approximated by the measured reflectance(ρ)of window, such as SC=0.475ρ~2-1.48p+1.0