THE IMPROVED POLYNOMIAL REPRESENTATION FOR DELTA-SHAPED SCATTERING INDICATRICES

A.D. Gadzhiev, S.B. Serov
VANT. Ser.: Mat. Mod. Fiz. Rroc 1990. Вып.1. С. 32-34.

      Basing on the improved polynomial representation for the σ-function, the improved P_N-approximation is constructed for high-stretched scattering indicatrices. This problem arises when solving the transport equation with highly anisotropic particle scattering. The improved polynomial representation has a number of advantages over the traditional P_N-approximation, the major of them is the positivity property.
      The paper presents formulas of the improved P_N-approximation for σ-shaped indicatrices. The P_N-approximation is graphically compared with the improved polynomial approximation for the σ-function.

      The paper describes the use of the finite-difference RHOMB method for numerically solving 2D unsteady equations of radiation transport in multigroup P₁-approximation.
      The two-stage iterative Jacobi method is used for jointly solving the multigroup system of P₁-equations and the energy equation.