Abstract The paper discusses the computational fluid dynamics simulation results of a bluff body. A literature case regarding a closed box section of a suspended bridge was selected since it is of practical relevance. An OpenFOAM implementation of a Spalart–Allmaras local correlation based transition model for Reynolds Averaged Navier–Stokes (RANS) equations was used as flow model. Locally-formulated RANS transition models were coupled with the Spalart–Allmaras (SA) model to reduce the computational cost with respect to the SST k − ω model. This model, named γ − R θ , t ˜ -SA, was successfully applied on airfoil sections and results are given by literature. In this paper, we present a set of computations of the flow field around a bluff body in order to stress the need to take into account transition effects in these kind of applications. The measure of the proposed model reliability was attested comparing experimental pressure coefficients and aerodynamic forces on the bridge section; besides, the effects of the model predictions on the critical flutter velocity, estimated by FEM and 2DOF Scanlan model of a pedestrian bridge structure, was examined as case of study.

中文翻译：

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钝体空气动力学的计算研究：层流到湍流过渡建模的影响。

摘要 本文讨论了钝体的计算流体动力学模拟结果。选择了一个关于悬索桥封闭箱形截面的文献案例，因为它具有实际意义。雷诺平均纳维-斯托克斯 (RANS) 方程的基于 Spalart-Allmaras 局部相关的转换模型的 OpenFOAM 实现被用作流动模型。局部制定的 RANS 转换模型与 Spalart-Allmaras (SA) 模型相结合，以降低 SST k - ω 模型的计算成本。该模型命名为 γ − R θ , t ～ -SA，已成功应用于翼型截面，结果由文献给出。在本文中，我们提出了一组钝体周围流场的计算，以强调在此类应用中考虑过渡效应的必要性。通过比较实验压力系数和桥段上的空气动力，证明了所提出模型的可靠性；此外，模型预测对人行天桥结构的 FEM 和 2DOF Scanlan 模型估计的临界颤振速度的影响作为研究案例进行了检查。