Abstract Triply Periodic Minimal Surfaces are attractive porous media for the design of volumetric solar energy receivers; their design involves the evaluation of their heat transfer capabilities in the mixed conductive/radiative mode. We present image-based computations of effective thermal conductivities (ETC) for different radiation/conduction ratios in twenty distinct TPMS structures, using a Hybrid Random Walk numerical method, considering Opaque/Transparent media. Results are cast in simple analytical correlations : the ETC is the sum of a purely conductive contribution proportional to the relative density and of a radiative contribution proportional to the radiation/conduction ratio; the coefficient of proportionality contains an emissivity-independent contribution and another contribution proportional to the emissivity which fades out above a critical ratio. This critical ratio is linearly proportional to the solid/void volume ratio of the media. These results are compared to similar ones obtained on open-cell foams. Application of these dimensionless laws to two realistic cases are presented as illustrative examples.

中文翻译：

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计算由三重周期最小表面定义的多孔介质的传导辐射有效热导率

摘要 三周期极小曲面是用于设计体积太阳能接收器的有吸引力的多孔介质；他们的设计涉及评估其在混合传导/辐射模式下的传热能力。我们使用混合随机游走数值方法，考虑不透明/透明介质，针对 20 种不同的 TPMS 结构中的不同辐射/传导比提出基于图像的有效热导率 (ETC) 计算。结果以简单的分析相关性表示：ETC 是与相对密度成正比的纯传导贡献和与辐射/传导比成正比的辐射贡献之和；比例系数包含一个与发射率无关的贡献和另一个与在临界比率之上逐渐消失的发射率成正比的贡献。该临界比率与介质的固体/空隙体积比率成线性比例。这些结果与在开孔泡沫上获得的类似结果进行了比较。这些无量纲定律在两个实际案例中的应用作为说明性示例呈现。