Radiative Exchange in Enclosures—The Zone Method

Total Exchange Areas When an enclosure contains reflective surface zones, allowance must be made for not only the radiant energy transferred directly between any two zones but also the additional transfer attendant to however many multiple reflections which occur among the intervening reflective surfaces. Under such circumstances, 

In what follows, conventional matrix notation is strictly employed as in A = [a,j] wherein the scalar subscripts always denote the row and column indices, respectively, and all matrix entities defined here are denoted by boldface notation. Section 3 of this handbook, Mathematics, provides an especially convenient reference for introductory matrix algebra and matrix computations. 

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