Abstract The effect of corner rounding on the flow past a cube is investigated numerically at different Reynolds numbers ranging from 50,000 to 200,000 using delayed detached-eddy simulation in OpenFOAM. Different corner radii from 0 to 40% of the cube length have been considered. To validate the adopted methodology, a benchmark case on the flow over a sphere with the same characteristic length is first performed. Good agreement has been achieved between the results of the benchmark and available experimental and numerical data from literature. Subsequently, features of the flow around cubes with rounded corners are investigated, including the aerodynamic coefficients, mean flow patterns and the surface pressure distribution. The relation between flow features and the aerodynamic coefficients is also analysed. In addition, the far-field noise emitted from the rounded cube is predicted using the Ffowcs William-Hawkings acoustic analogy in FLUENT. It is found that corner rounding with carefully determined radius can be an effective way to reduce the emitted noise. The minimum noise is found for a radius 1/3 of the cube side length with the lowest surface pressure fluctuations, but the sound level increases again for a further increase in corner radius to R/L = 2/5 due to vortex shedding.

中文翻译：

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圆角立方体上的流动和噪声的数值研究

摘要 使用 OpenFOAM 中的延迟分离涡流模拟，在从 50,000 到 200,000 的不同雷诺数下，数值研究了圆角对流过立方体的影响。已经考虑了从立方体长度的 0% 到 40% 的不同角半径。为了验证所采用的方法，首先对具有相同特征长度的球体上的流动进行基准案例。基准的结果与文献中可用的实验和数值数据之间取得了良好的一致性。随后，研究了圆角立方体周围流动的特征，包括气动系数、平均流动模式和表面压力分布。还分析了流动特征与气动系数之间的关系。此外，使用 FLUENT 中的 Ffowcs William-Hawkings 声学类比来预测从圆形立方体发出的远场噪声。结果表明，仔细确定半径的圆角可以是减少发出的噪声的有效方法。在具有最低表面压力波动的立方体边长的半径 1/3 处发现最小噪声，但由于涡旋脱落，当拐角半径进一步增加至 R/L = 2/5 时，声级再次增加。