Numerical investigations of rotating cylindrical micro vortex generators for turbulent boundary layer separation control

本申请旨在利用一种名为微型旋转柱面涡流发生器(MRCVG)的新装置来进行流动控制的基础研究。初步工作表明，安装在壁面上的旋转圆柱头(其旋转轴垂直于壁面)在层流和湍流边界层流动中产生持续时间较长的流向涡流和高速条纹。根据已证实的壁面摩擦系数的增加，可以直接考虑将mRCVG作为一种可能的湍流分离控制的新手段。目前的工作将试图确定那些在mRCVG下游产生最大平均表面摩擦的参数，然后将这些参数应用到由圆形坡道上的湍流组成的试验构型中。为了考虑非定常影响和深入了解流动动力学，将使用大涡模拟。在作者的期望中，mRCVG有可能成为一种简单且可能稳健的方法，这是以前从未在流体力学中研究过的分离控制方法。

The present application is intended to perform fundamental research on flow control using a new device, called micro Rotating Cylindrical Vortex Generators (mRCVG). Preliminary work has shown that wall-mounted rotating cylinder stubs (with their rotation axis perpendicular to the wall) generate long-lasting streamwise vortices and high-velocity streaks in laminar as well as in turbulent boundary-layer flows. With an according, already verified increase of the skin friction coefficient, it is straightforward to consider mRCVGs as a possible new means for turbulent flow separation control. The present work will try to identify those parameters which yield a maximal mean skin friction downstream of the mRCVGs and then apply these to a test configuration consisting of a turbulent flow over a rounded ramp. Large-Eddy Simulation will be used in order to consider unsteady effects and obtaining insight into the flow dynamics. In the authors’ expectation mRCVGs have the potential to become a simple and presumably robust method which has never been investigated before for separation control in fluid dynamics.