Abstract: Four basic types of integration of radiative exchange area are generalized using general symmetry and applied to ten kinds of computation.The kinds of partial blocks of the matrix of radiative direct exchange area are analyzed,and the whole matrix is classified into four types of partial areas.Utilizing general symmetry,the quantitative expressions for the computation reduction of the direct exchange area of both three dimensional and two dimensional systems are presented.

Key words: general symmetry, radiative direct exchange area, zone method