Abstract The present paper aims to explore and gain more knowledge about the viscosity effect on a shallowly submerged UV hydrodynamics. For this purpose, the hydrodynamic drift tests are performed on the generic SUBOFF UV geometry using URANS equations with a Reynolds stress turbulence model and Euler equations available in the commercial code STARCCM+. The simulations are conducted for drift angles ranging from β = 0 to β = 18 . 11 ∘ at a Froude number equal to F n = 0.512 in two different scenarios: with and without the presence of the free surface. The simulations with the presence of the free surface are performed using both URANS and Euler equations at a submergence depth h = 1.1 D (D: UV maximum diameter), while the simulations without the presence of the free surface are carried out using only the URANS equations. Although the Euler simulations appear to predict reasonably well the free surface contribution to the axial and lateral forces acting on the UV, further analysis of the results reveals that, generally, the viscosity has a non-negligible influence on the UV hydrodynamics and, consequently, on the loads acting on the UV. This is true even at zero incidence with respect to the incoming flow, where the Euler simulations are expected to provide satisfactory results due to the absence of large flow separation over the UV.

中文翻译：

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粘度对无水下航行器表面水动力相互作用的影响

摘要 本文旨在探索并获得更多关于粘度对浅水淹没紫外线流体动力学影响的知识。为此，使用带有雷诺应力湍流模型的 URANS 方程和商业代码 STARCCM+ 中可用的欧拉方程，在通用 SUBOFF UV 几何上执行流体动力学漂移测试。对范围从 β = 0 到 β = 18 的漂移角进行模拟。11 ∘ 在 Froude 数等于 F n = 0.512 的两种不同情况下：有和没有自由表面的存在。存在自由表面的模拟使用 URANS 和 Euler 方程在淹没深度 h = 1.1 D（D：UV 最大直径）下进行，而不存在自由表面的模拟仅使用 URANS 进行方程。尽管 Euler 模拟似乎可以合理地预测自由表面对作用在 UV 上的轴向和横向力的贡献，但对结果的进一步分析表明，通常，粘度对 UV 流体动力学具有不可忽略的影响，因此，关于作用在 UV 上的载荷。即使在相对于传入流的零入射情况下也是如此，由于在 UV 上不存在大的流分离，因此预计欧拉模拟将提供令人满意的结果。