Stationary transport with partially reflecting boundary conditions. II

摘要

We consider the stationary monoenergetic transport equation (the Lorentz model) in a semiinfinite geometry with most general nonmultiplying boundary conditions at the wallx=0, accounting for absorption, specular, diffuse, and lsquo;lsquo;selectiversquo;rsquo; reflection, or combinations thereof. Performing the numerical study of a (partially) lsquo;lsquo;thermalizingrsquo;rsquo; wall, we investigate the density profilen(x), the Milne extrapolation lengthxM, and the space dependent diffusion coefficientD(x) as functions of the accomodation and lsquo;lsquo;selectionrsquo;rsquo; coefficients. The inversed density profile (equivalent to a negative diffusion coefficient) is numerically computed. As a simple analytically solvable example, a discrete velocity model is discussed in the Appendix.