模拟辐射传热的离散坐标法的改进

针对离散坐标法模拟求解炉内辐射换热的问题,在对辐射传递方程采用控制容积法离散时,按辐射方向上各界面之间的投影关系划分区域,对辐射传递方程在各子控制体上沿辐射传输方向进行积分,求解各子控制体的辐射强度,再取容积平均值作为最终节点的辐射强度的新离散坐标方法,定义为分段积分离散坐标法,并对三维矩型燃气炉内辐射换热进行了数值模拟,与传统离散坐标方法及区域法进行了比较,比较结果表明新离散坐标法较好的解决了假散射问题,提高了离散坐标法的精度.

An Improvement on the Discrete Ordinate Method in Simulating Radiative Heat-transfer

An improvement on the Discrete Ordinate Method (DOM)-‘divide and rule’is shown. The tiny dominated body is plotted into districts according to the projection relation between the interfaces in the radiative heat-transfering direction. The radiative intensity of the subsidiary dominated bodies is solved after an integral to the radiative heat-transfering equation in the radiative heat-transfering direction. In the new DOM, the average volume is regarded as the final radiative intensity of the nodes. Numerical simulation is performed on the process of radiative heat-transfer in a three-dimension rectangular furnace. Compared with the traditional DOM and the district method, numerical results indicate that the new DOM solves the fake scattering preferably, and ameliorates the precision of the calculation as well.