辐射离散传播法在三维圆柱腔体辐射传热计算中的应用

运用空间解析几何理论与数值计算相结合的方法，实现了辐射离散传播法（OTM）在三维圆柱腔体内辐射传热计算的应用。采用坐标转换建立了辐射射线方程，通过直接求解所有发射点上各立体角内的辐射射线与各辐射单元体的交点，确定射线经过的路径及各交点与发射点的距离，然后按距离远近对交点进行排序，得到适合DTM法求解辐射能量传递方程的交点顺序。运用该方法对圆柱腔体内辐射换热进行三维计算，得到与精确解基本相符的结果；将DTM法运用于煤粉燃烧火焰辐射换热的计算，得到的温度场与实验结果基本一致，表面辐射热流密度分布合理，由此表明本文设计的方法是可行的。

The Application of a Radiation Discrete Transfer Method for the Radiation Heat Transfer Calculation of a Three-dimensional Cylindrical Cavity Body

By employing a method combining spatial analytical geometry theory with numerical calculations a radiation discrete transfer method(DTM) was implemented for the radiation heat transfer calculations in a three-dimensional cylindrical cavity body.Through the use of coordinate transformation a radiation ray equation was set up.By directly solving the intersection points of the radiation rays in various three-dimensional angles with various radiation unitary bodies at all emission points determined were the path traversed by the rays and the distance between the various intersecting points and emission points.Then,with the intersecting points being arranged in proper order,and taking into account the magnitude of the above-mentioned distance,one can obtain the intersecting point sequence for solving the radiation energy transfer equation in adaptation to the DTM method.The above-mentioned method was used to perform a three-dimensional calculation of the radiation heat exchange in the cylindrical cavity body and the computation results are in basic agreement with those of a precision solution.The DTM method was employed for calculating the radiation heat exchange in a pulverized-coal combustion flame.The temperature field being obtained basically agrees with that of experimental results and the surface radiation heat-flux density assumes a rational distribution.This shows that the method designed by the authors is feasible.