AN APPROXIMATE CALCULATION OF ANGULAR DISTRIBUTION COEFFICIENTS FOR THERMAL RADIATION FROM A ROTATION SURFACE

Yu. A. Dementiev, R. F. Mashinin, V. F. Mironova, N. N. Chentsov
Vant. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki 1983. Вып.1. С. 32-34.

      The Babayev equation is used to describe a time-dependent thermal radiation transport through a region with a negligibly weak material/radiation interaction in terms of delaying and shadowing effects. The cavity surface is assumed to be composed of several rotation surfaces with respect to a common axis. A calculational grid is mapped onto the cavity surface and the equation is approximated by a system of algebraic equations. The equation coefficients are geometrically considered as angular coefficients and average distances; so their estimations requires four-gold integerals to be calculated over a complex integration region. A procedure for approximate calculation of coefficients relying, when possible, on analytic computations is described.