处理辐射传热的一个热流数学模型

A MATHEMATICAL MODEL OF HEAT FLUX FOR RADIATIVE HEAT TRANSFER

本文从辐射与传输的最基本原理出发,引进等价热流、正向投射热流,反向投射热流、正向赝投射热流及反向赝投射热流概念,定义出一个具有统计意义的比热流参数,建立了一般情况下的热流微分方程,并在几种特殊入射强度分布的情况下用Monte-Carlo方法求解出比热流参数的具体值。对于工程上的实际问题,在简化条件下给出了计算比热流参数的具体公式,同时给出常用情况下的边界条件,构成了完备的数学模型。该模型与文献[2]中的模型有所不同,能较好地说明文献[2]方程计算结果偏小的问题。

IN this paper, based on the basic principle of radiaiton and transfer, a set of differential equations of the heat flux in a general case were established by defining the specific heat flux, which possesses statistical meaning, and conceptions of equivalent heat flux, heat flux of direct irradiation, heat flux of reverse irradiation, and pseudo heat flux of direct (or reverse) irradiation. The values of specific heat flux parameter under several specific distributions of incident radiation were obtained by means of Monte-Carlo method. For engineering questions, the formulas for calculating the specific heat flux parameter were given under simplified conditions. Meanwhile, the boundary conditions for common cases were given as well. All of them form a perfect mathematical model which differs from the model published in the paper [2], and would be much better in explaining the problem occured in the same paper [2] where the calculated results were smaller than the measured ones.