Effects of Bulbous Bow on Cross-Flow Vortex Structures Around a Streamlined Submersible Body at Intermediate Pitch Maneuver： A Numerical Investigation

在在一个中间的入射角的优化身体附近的一块流动地被跨流动的分离和旋涡的流动地统治。分开的流动在身体的 leeside 上导致一双旋涡；因此，精确地决定这对并且估计它的尺寸和地点是必要的。这研究基于 RANS 方程利用基于元素的有限体积方法在 SUBOFF 赤裸的 submarined 壳附近计算 3D axisymmetric 流动。跨流动的旋涡结构然后数字地与 SUBOFF 和 DRDC STR 弓为一艘潜水艇被模仿并且比较。计算结果迫使并且砍旋涡结构的壳表面和力量和地点上的压力分发在 20 的一个中间的发生角度被介绍？？

Experimental investigation of typical surface treatment effect on velocity fluctuations in turbulent flow around an airfoil

Noise reduction of different airfoils is important because these sections are used in wind turbines,propellers,and aircraft wings.Several methods are used for passive noise reduction of sections.One of these methods is the use of surface treatment.In this research,the effect of the typical surface treatment element(finlets)on the vortex structure at different frequencies in the turbulent flow created on the NACA2412 section is investigated.For this purpose,one-dimensional hot wire probe is used.The used surface treatment in this research has a special geometry and the distance between two consecutive finlets is 6 mm(S=6 mm).This study shows that this surface treatment element can be used for noise reduction in high frequencies.Another result of this research is the suggestion of the most suitable position to install this special surface treatment element to reduce vortex energy in all frequency ranges.This installation location is determined based on a dimensionless parameter(X_(aft)/h).