Construction and investigation of schemes for the calculation of radiative transfer

The paper examines two types of difference schemes for solving the equations of nonstationary spectral-radiation transfer in a moving, scattering gas in the case of spherical symmetry. The stability of these schemes is analyzed and their convergence is demonstrated, and it is shown that they are suitable for the calculation of stationary radiative transfer. Schemes of the first type (yielding correct results for large optical sizes of absorption and scattering cells when the local approximation is absent) are associated with the variational principle for the half-difference of radiation intensity, while schemes of the second type are associated with the Vladimirov variational principle for the half-sum of intensity.