Daylight Calculation under All-Weather Conditions and Prediction of Luminous Environment for the Membrane Structures with Open and Closed Roof

Validation of daylight calculation for an anisotropic diffuse reflecting interior of arbitrary geometry under any sky conditions

“…Theory The reflectance R(Bi,di) of the surface in the given direction of incidence is obtained by integrating the LIC over the hemisphere above the surface, R(ei,di) =~z~~~' z~(~i ,~i ;~o ,~o ) s i n~o d~o ddo. (2) The LIC has a relation to other indexes of the directional reflection property [6] under the same condition of incidence and reflection as follows, p = (pv cos eo = qu cos eo = fr cos eo (3) where, pV is the luminance factor [-I, qv is the luminance coefficient [l/sr], and fr is the bidirectional reflectance distribution function (BRDF) [l/sr].…”

“…Then the other array of Lrrx is calculated by solving the equations (4) with the iterative method. 3 illustrates the reflection mechanism of a nonmetallic or nonconducting material [7]. The reflected light on the surface of a non-metallic material is generally composed of two components, namely, the boundary reflected component and the layer reflected one.…”

“…In these studies, it is noted that the practical use of computer simulation is limited to a design of relatively simple geometry and isotropic diffuse reflecting property. However recent studies have made it possible to perform lighting calculation on a design of arbitrary geometry [3] and anisotropic diffuse reflecting property [4].…”