求解辐射传递方程的离散坐标法

阐述了含吸收散射性介质三维空腔内辐射传递方程的离散坐标解法。讨论了入射散射项积分格式的选取,以及假散射和射线效应对解精度的影响。对三维矩形炉膛内辐射传递过程进行了数值模拟,并与区域法和离散传递法进行比较。比较结果表明离散坐标法具有较好的精度,是目前燃烧室内辐射传热过程数值模拟的一种较好的方法。

DISCRETE ORDINATE SOLUTIONS OF RADIATIVE TRANSFER EQUATION

The discrete ordinate approximation method of three-dimensional radiative transfer equation in absorbing scattering medium is expounded. The selection of quadrature sets of in-scattering term are analysed. The causes about the formation of false scattering and ray effect and its influence on the accuracy of solutions are also analysed. By detailed comparison, it is shown that false scattering and ray effect exact not only in discrete-ordinates method, but also in zone method, discrete transfer method, etc., and the influence of false scattering and ray effect on solution accuracy of radiative transfer equation can be reduced by decreasing grid size and increasing the number of solid angle discretation. The process of radiative heat transfer in a three-dimension rectangular furnace is simulated using discrete ordinates method. By comparison with zone method and discrete transfer method, it is found that discrete ordinates method has a good accuracy, and recently is one of the best method to simulate the process of radiative heat transfer in furnace.