On irradiant coefficient.

The paper considers the calculation of the value of the irradiation coefficient between the surfaces. According to the definition, irradiation coefficient is the surface integral of the second kind and geometrical characteristic of surfaces interposition. Defining the formula to calculate the value of these coefficients is very difficult. There were obtained formulas in [1] for calculating these coefficients of arbitrary surfaces. Although cubic formulas are introduced in [2, 3, 4] to numerically calculate these coefficients. [ABSTRACT FROM AUTHOR]