Abstract We present a novel algorithm to calculate radiative energy transfer rates in Discrete Element Method (DEM)-based simulations of mono-disperse spheres. To verify our algorithm we use the Finite Volume Method (FVM) which enables us to picture relevant radiation phenomena in a dense bed of particles. These phenomena include (i) shadowing, (ii) emission and (iii) adsorption by a constant gray medium. After careful verification, we embed our algorithm in LIGGGHTS , a solver for the DEM. A combination of LIGGGHTS and a solver for intra-particle temperature gradients, i.e., ParScale , is then used to quantify the relevance of radiative heat transfer rates in sheared particles beds. Specifically, we evaluate the relative contributions of conductive, convective and radiative thermal fluxes in granular shear flows of frictional inelastic spheres. We find that the radiative flux can be collapsed onto single curve if it is related to an appropriate dimensionless group. Our analysis establishes a rationale on when radiative heat transfer in dense granular flows should be considered or not. Also, our results can be used to close continuum-based granular dynamics model that aim on predicting the particle temperature distribution under extreme temperature scenarios.

中文翻译：

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在耦合粒子模拟中计算辐射热交换的新方法

摘要 我们提出了一种在基于离散元方法 (DEM) 的单色散球体模拟中计算辐射能量转移率的新算法。为了验证我们的算法，我们使用了有限体积法 (FVM)，它使我们能够描绘密集粒子床中的相关辐射现象。这些现象包括 (i) 阴影、(ii) 发射和 (iii) 恒定灰色介质的吸附。经过仔细验证，我们将算法嵌入到 DEM 求解器 LIGGGHTS 中。然后使用 LIGGGHTS 和颗粒内温度梯度求解器的组合，即 ParScale 来量化剪切颗粒床中辐射传热速率的相关性。具体来说，我们评估了摩擦非弹性球体的颗粒剪切流中传导、对流和辐射热通量的相对贡献。我们发现，如果辐射通量与适当的无量纲组有关，则它可以折叠成单条曲线。我们的分析确定了何时应该考虑密集颗粒流中的辐射传热的基本原理。此外，我们的结果可用于关闭基于连续体的颗粒动力学模型，该模型旨在预测极端温度情景下的颗粒温度分布。