In this paper analysis is performed on a computational method for thermal radiative transfer (TRT) problems based on the multilevel quasidiffusion (variable Eddington factor) method with the method of long characteristics (ray tracing) for the Boltzmann transport equation (BTE). The method is formulated with a multilevel set of moment equations of the BTE which are coupled to the material energy balance (MEB). The moment equations are exactly closed via the Eddington tensor defined by the BTE solution. Two discrete spatial meshes are defined: a material grid on which the MEB and low-order moment equations are discretized, and a grid of characteristics for solving the BTE. Numerical testing of the method is completed on the well-known Fleck-Cummings test problem which models a supersonic radiation wave propagation. Mesh refinement studies are performed on each of the two spatial grids independently, holding one mesh width constant while refining the other. We also present the data on convergence of iterations.

翻译：本文对基于长特征线法（射线追踪）求解玻尔兹曼输运方程（BTE）的多层级准扩散（可变爱丁顿因子）热辐射输运（TRT）计算方法进行了分析。该方法采用BTE的多层级矩方程组，并与材料能量平衡（MEB）方程耦合。矩方程组通过BTE解定义的Eddington张量实现精确闭合。空间离散采用两套独立网格：用于离散MEB方程和低阶矩方程的材料网格，以及用于求解BTE的特征线网格。本文在经典的Fleck-Cummings测试问题（模拟超声速辐射波传播）上完成了数值验证，并独立对两套空间网格进行网格细化研究——在保持一套网格尺寸不变的同时细化另一套。此外还给出了迭代收敛数据。