THE SIMPLIFIED P-2 APPROXIMATION

The simplified P-2 (SP2) approximation to the transport equation is de rived by aformaiprocedure and by a variational analysis. The variation al analysis yields the SP2 equations, together with interface and Mars hak-like boundary conditions. Numerical calculations show that the res ulting SP2 solution is generally more accurate than the P-1 solution f or both integral quantifies and detailed flux distributions, except ne ar material interfaces, where the SP2 solution is discontinuous.