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本文通过数值模拟方法研究了高温下加热 /冷却管内层流充分发展流动的参与性介质热起始段的辐射与对流耦合换热。采用离散坐标法求解圆柱坐标系下的非线性积分微分辐射传递方程 ,采用有限差分法求解辐射与对流的耦合换热能量方程。通过计算 ,分析了不同壁温及入口温度下 ,介质导热系数、壁面发射率、介质散射反照率及散射相函数等因素对局部努谢尔数、壁面热流密度及有效加热 /冷却长度的影响 ,并同时采用努谢尔数和壁面热流密度评价了耦合换热中辐射对对流换热的影响。
In this paper, the radiation and convection-coupled heat transfer in the hot starting section of the participating medium during the full development of the laminar flow in the heating / cooling tube at high temperature were studied by means of numerical simulation. The discrete coordinate method is used to solve the nonlinear integral differential radiation transfer equation in the cylindrical coordinate system. The finite difference method is used to solve the coupled heat and energy equations of radiation and convection. The influences of different thermal conductivity, wall emissivity, medium scattering albedo and scattering phase function on the local Nusselt number, wall heat flux density and effective heating / cooling length were analyzed by calculation. At the same time, the effect of radiation on convective heat transfer in coupled heat transfer was evaluated by Nusselt number and wall heat flux density.