具有二维特征辐射换热问题数值计算的降维处理

辐射换热通常按三维方法计算。本文针对具有二维特征的辐射换热问题，提出一种降维处理方法。与三维方法不同的是，降维后的辐射强度I2D是在二维系统平面角的概念上导得的，其值为辐射力E的一半，即I2D＝E／2。经过降维处理后的数值方法使得具有二维特征辐射传热问题的计算得到极大简化。对含有参与性介质的圆筒形腔体和无限长方腕内的热持性进行计算，并将计算结果与按三维辐射计算的结果或精确结果进行比较，两者取得良好的一致性。

Dimensionality Reduction Method for Numerical Computation of Radiant Heat Transfer with Two-Dimensional Characteristics

Three dimensional radiant heat transfer is usually calculated even in the case of those with two dimensional characteristics.In this paper,a new dimensionality reduction method for calculating the radiant heat transfer with two dimensional characteristics was defined on the basis of a plane angle.The numerical relationship between the radiation intensity I 2D and the emissive power E,i.e.,I 2D =E/2,was also derived.And the numerical simulation was greatly simplified.Computations of thermal characteristics by dimensionality reduction method were performed for a cylindrical enclosure and an infinitely long square cavity,containing a medium of constant absorption coefficient.Satisfactory agreements with the results by analytical or three dimensional radiation method were obtained.