抄録
In order to make good use of solar energy, it is important to analyse the illuminance distribution due to skylight under various condition. In this paper, under two sky condition, CIE standard overcast sky and uniform sky, the illuminance distribution due to skylight incident from sky through perpendicular side face onto interior surfaces of a solid with a shape of rectangular parallelepiped is analysed. As a result, a series of equations for calculating direct illuminance at an arbitrary point on the interior surfaces and luminous flux incident directly on an arbitrary interior surface is proposed, and the total ratio of luminous flux distributed on interior surfaces (the base, side wall, front wall) to total luminous flux incident inside through perpendicular side face is graphed.
