An in-house CFD code has been developed to address the coupling between natural convection and surface radiation in irregular geometries encountered in cooling electronic components. In the current numerical study, the discrete ordinate methods with the concept of blocked-off region are used in order to investigate the conjugate natural convection and surface radiation in an enclosure containing a wavy inner circular cylinder. The validity of the numerical code is ascertained by comparing our results with previously published results dealing with the limiting case of a smooth circular cylinder enclosed in a cavity. Extensive computations have been performed to study in detail the effect of the Rayleigh number ( $$10^{3} \le {\text{Ra}} \le 10^{7}$$ 10 3 ≤ Ra ≤ 10 7 ), the inner and outer surface emissivities ( $$0 \le \upvarepsilon_{{{\text{E}}\,{\text{or I}}}} \le 1$$ 0 ≤ ε E or I ≤ 1 ), the undulations number ( $$4 \le {\text{N}} \le 1 2$$ 4 ≤ N ≤ 12 , their amplitude ( $$0 \le {\upalpha} \le 1$$ 0 ≤ α ≤ 1 ) and the average radius of the wavy circular cylinder ( $$0.05 \le {\text{R}}_{ 0} \le 0.25$$ 0.05 ≤ R 0 ≤ 0.25 ) on the flow structure as well as on the convective and radiative heat transfer characteristics. The obtained results showed that the amplitude and the average radius have more significant effect on the total heat transfer rate than the undulations number of the wavy wall.

中文翻译：

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内波浪体方腔内的自然对流和表面辐射传热

已经开发了内部 CFD 代码来解决冷却电子元件中遇到的不规则几何形状中自然对流和表面辐射之间的耦合。在当前的数值研究中，使用具有封闭区域概念的离散纵坐标方法来研究包含波浪形内圆柱体的外壳中的共轭自然对流和表面辐射。通过将我们的结果与先前发表的处理封闭在空腔中的光滑圆柱体的极限情况的结果进行比较，可以确定数值代码的有效性。已经进行了广泛的计算来详细研究瑞利数的影响 ( $$10^{3} \le {\text{Ra}} \le 10^{7}$$ 10 3 ≤ Ra ≤ 10 7 )，内表面和外表面发射率 ( $$0 \le \upvarepsilon_{{{\text{E}}\, 25) 关于流动结构以及对流和辐射传热特性。所得结果表明，振幅和平均半径对总传热率的影响比波浪壁的起伏数更显着。25) 关于流动结构以及对流和辐射传热特性。结果表明，振幅和平均半径对总传热率的影响比波浪壁的起伏数更显着。