Particle-laden flow in a vertical channel was simulated using a Reynolds-averaged Navier–Stokes (RANS) two-fluid model including a Reynolds-stress model (RSM). Two sets of cases varying the overall mass loading were done using particle sizes corresponding to either a large or small Stokes number. Primary and turbulent statistics extracted from counterpart Eulerian–Lagrangian (EL) and Eulerian–Eulerian Anisotropic-Gaussian (EE-AG) simulations were used to inform parameters and closures applied in the RSM. While the behavior at the center of the channel compared well with the other simulations, including the transition from fully-developed turbulent flow to relaminarization to cluster-induced turbulence (CIT) as the mass loading increased, the behavior close to the wall deviated significantly. The primary contributor to this difference was the application of a uniform drag coefficient, which resulted in the RSM overpredicting the fluid-phase turbulent kinetic energy close to the wall. When considering small-Stokes particles, the RSM at greater mass loadings reproduced the transient clustering observed in the other models. This was not observed using larger particles.

中文翻译：

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含颗粒垂直通道流中团簇引起的湍流的雷诺应力模型

使用包括雷诺应力模型（RSM）的雷诺平均Navier–Stokes（RANS）两流体模型模拟了垂直通道中的载有颗粒的流动。使用对应于较大或较小斯托克斯数的粒径，完成了两组改变总质量负荷的案例。从对应的欧拉-拉格朗日（EL）和欧拉-欧拉各向异性高斯（EE-AG）模拟中提取的原始和湍流统计信息可用于RSM中应用的参数和闭合。虽然通道中心的行为与其他模拟比较好，包括随着质量载荷的增加从完全发展的湍流过渡到再分层再到簇诱导的湍流（CIT），但靠近壁的行为明显偏离。造成这种差异的主要原因是均匀的阻力系数的应用，这导致RSM过度预测了靠近壁的液相湍流动能。当考虑小斯托克斯粒子时，在较大质量载荷下的RSM重现了其他模型中观察到的瞬态聚类。使用较大的颗粒未观察到这一点。