We address the capability of large eddy simulation (LES) to predict the physics of density currents interacting with bluff obstacles. Most density currents of interest in engineering and geophysical applications interact with obstacles or topographic features. Validating LES solutions in these contexts is crucial to establish it as a trusted tool. We thus propose a validation effort based on simple geometries that nonetheless pose challenges common to more complex systems, including boundary layer separation and convective instabilities. We focus on lock-exchange gravity currents in the slumping phase interacting with an emergent vertical circular cylinder. Our main investment was in ensuring that the comparison of experimental data and numerical results include, at least, the velocity and the density fields , and derived quantities (e.g., second order moments). Measurements of both density and velocity fields were performed in the side and plan views for cylinder Reynolds numbers, \(Re_d\), in the range 1300 to 3475. It was found that the LES accurately predicts the temporal evolution of the current front position. The computed front velocity exhibits a maximum relative error less than 8%. A good agreement between the LES and the experimental size and shape of the current head, and billows was found. The overall features upstream the cylinder, including a reflected wave, adverse pressure gradient and backflow, and downstream the cylinder, including the backflow, wake and the formation of a new head are well reproduced by LES. The agreement between the LES and the experimental time-space evolution of current spanwise- and depth-averaged density contours and the instantaneous velocity fields are not affected by \(Re_d\).

我们解决了大涡模拟 (LES) 的能力，以预测密度电流与断崖障碍物相互作用的物理特性。工程和地球物理应用中感兴趣的大多数密度流与障碍物或地形特征相互作用。在这些环境中验证 LES 解决方案对于将其确立为值得信赖的工具至关重要。因此，我们提出了一种基于简单几何形状的验证工作，但这些几何形状对更复杂的系统提出了常见的挑战，包括边界层分离和对流不稳定性。我们专注于在滑落阶段与涌现的垂直圆柱相互作用的锁交换重力流。我们的主要投资是确保实验数据和数值结果的比较至少包括速度和密度场，以及导出量（例如，二阶时刻）。密度和速度场的测量是在圆柱雷诺数的侧视图和平面视图中进行的，\(Re_d\)，在 1300 到 3475 的范围内。发现 LES 准确地预测了当前前沿位置的时间演变。计算的前沿速度表现出小于 8% 的最大相对误差。LES 与当前头部的实验尺寸和形状以及波浪之间的一致性很好。圆柱体上游的整体特征，包括反射波、逆压梯度和回流，以及圆柱体下游的整体特征，包括回流、尾流和新水头的形成，都被 LES 很好地再现了。LES 与当前展向和深度平均密度等值线的实验时空演化和瞬时速度场之间的一致性不受\(Re_d\)的影响。