关键词: 坡面, 天文辐射, 椭圆积分

Abstract: In this paper authors discussed the methods of computing the extraterrestrial solar radiation onthe slope.Then,the authors studied the combined relations of the sunrise and sunset hour angleswhich is composed of the sunrise and sunset hour angles on horizental surface and non-horizentalsurface on the slope and their variational Laws.Based.on these,the authors established the ellipticalintegral model with the expressions of elliptical integral,which is used to compute the extraterrestrial solar radiation on the slope with any orientation and gradient during any period.The resultesof the model test show that it is correct thoroughly.The elliptical integral model is severe in theory.It can be used to find and prove many natures of the extraterrestrial solar radiation on the slope.

Key words: slope, extraterrestrial solar radiation, elliptical integral