Abstract

We present results for a direct numerical simulation study of isothermal incompressible flow in a regularly packed pebble-bed domain with a bounding wall. We focus specifically on the near-wall behavior of the flow. Our simulation is carried out at a Reynolds number of 9308 to facilitate cross verification with available high-fidelity data. To reduce the required time to achieve statistically stationary results, we implemented an ensemble-averaging scheme that allowed for multiple simulation runs to be carried out concurrently. The close packing of the spheres in the domain causes significant acceleration effects in the domain, which result in boundary layer detachment and reattachment. Presented results include selected first- and second-order turbulence statistics, as well as selected terms of the turbulent kinetic energy transport equation. The acceleration effects in the near-wall region of the domain cause negative production of turbulent kinetic energy. The presented data may be useful for benchmarking Reynolds-averaged Navier-Stokes–based simulations of pebble beds.

摘要

我们提出了在具有边界壁的规则填充的卵石床域中等温不可压缩流动的直接数值模拟研究的结果。我们特别关注流动的近壁行为。我们的模拟在雷诺数 9308 下进行，以促进与可用的高保真数据的交叉验证。为了减少获得统计稳定结果所需的时间，我们实施了一个集成平均方案，该方案允许同时执行多个模拟运行。域中球体的紧密堆积在域中引起显着的加速效应，从而导致边界层脱离和重新附着。呈现的结果包括选定的一阶和二阶湍流统计数据，以及选定的湍流动能传输方程项。域近壁区域的加速效应导致产生负的湍流动能。所提供的数据可能有助于对基于雷诺平均 Navier-Stokes 的卵石床模拟进行基准测试。