Abstract Multiple reflections in a cavity geometry augment the emission and absorption of the cavity opening relative to a flat surface in a phenomenon known as the cavity effect. The extent of the cavity effect is quantified using apparent absorptivity and apparent emissivity. Analysis of complicated thermal systems is simplified through application of apparent radiative properties to cavity geometries. The apparent radiative properties of a specularly-reflecting, gray, isothermal V-groove have been derived analytically, but these results have not been validated experimentally or numerically. Additionally, the model for apparent absorptivity of an infinite V-groove subjected to partial illumination in the presence of collimated irradiation is not available. In this work, the following existing models for a specularly-reflecting V-groove are collected into a single source: (1) the apparent absorptivity of a diffusely irradiated V-groove, (2) the apparent emissivity of an isothermal V-groove and (3) the apparent absorptivity of a V-groove subject to collimated irradiation with full-illumination. Further, a new analytical model is developed to predict the apparent absorptivity of an infinite V-groove subject to collimated irradiation with partial-illumination. A custom, Monte Carlo ray tracing solver is used to predict the apparent radiative properties for all cases as a means of numerical verification by comparing the ray tracing data with the results from the new model in this work and the previously existing models. For diffuse irradiation, the analytical model and ray tracing data show excellent agreement with an average discrepancy of 4.4 × 10−4, verifying the diffuse-irradiation analytical model. Similar agreement is found for collimated irradiation, where the full and partial illumination models indicate average discrepancies of 4.9 × 10−4 and 4.6 × 10−4 when compared with ray tracing data.

中文翻译：

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具有镜面反射的无限 V 形槽的总半球视辐射特性

摘要 腔体几何结构中的多次反射增强了腔体开口相对于平坦表面的发射和吸收，这种现象称为腔体效应。使用表观吸收率和表观发射率来量化空腔效应的程度。通过将表观辐射特性应用于腔体几何形状，可以简化复杂热系统的分析。镜面反射、灰色、等温 V 型槽的表观辐射特性已通过分析推导出来，但这些结果尚未经过实验或数值验证。此外，在存在准直照射的情况下，无限 V 形槽受到部分照明的表观吸收率模型不可用。在这项工作中，镜面反射 V 型槽的以下现有模型被收集到一个来源中：(1) 漫射 V 型槽的表观吸收率，(2) 等温 V 型槽的表观发射率和 (3) V 型槽在全照度准直照射下的表观吸收率。此外，开发了一种新的分析模型来预测无限 V 形槽在部分照明的准直照射下的表观吸收率。自定义的蒙特卡罗光线追踪求解器用于预测所有情况下的表观辐射特性，作为数值验证的一种手段，方法是将光线追踪数据与本工作中的新模型和先前存在的模型的结果进行比较。对于漫射照射，分析模型和射线追踪数据显示出良好的一致性，平均差异为 4.4 × 10−4，验证了漫射辐射分析模型。准直辐照也有类似的一致性，与光线追踪数据相比，全照明和部分照明模型表明平均差异为 4.9 × 10−4 和 4.6 × 10−4。