Computational study of the vortex path variation with the VG height

The Science of Making Torque from Wind 2014

Fernández-Gámiz, U.^1 ; Zamorano, G.^1 ; Zulueta, E.^2

Nuclear Engineering and Fluid Mechanics Dep., University of the Basque Country, Nieves Cano 12, 01006 Vitoria-Gasteiz, Araba, Spain^1

Automatic and Simulation Dep., University of the Basque Country, Nieves Cano 12, 01006 Vitoria-Gasteiz, Araba, Spain^2

关键词: Boundary layer thickness;    Computational simulation;    Computational studies;    Flow separation control;    Passive control devices;    Primary vortex;    Vortex generators;    Vortex paths;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/524/1/012024/pdf
DOI  :  10.1088/1742-6596/524/1/012024

来源: IOP

【 摘 要 】

An extensive range of conventional, vane-type, passive vortex generators (VGs) are in use for successful applications of flow separation control. In most cases, the VG height is designed with the same thickness as the local boundary layer at the VG position. However, in some applications, these conventional VGs may produce excess residual drag. The so-called low-profile VGs can reduce the parasitic drag associated to this kind of passive control devices. As suggested by many authors, low-profile VGs can provide enough momentum transfer over a region several times their own height for effective flow-separation control with much lower drag. The main objective of this work is to study the variation of the path and the development of the primary vortex generated by a rectangular VG mounted on a flat plate with five different device heights h δ, h10.8δ, h20.6δ, h30.4δ and h40.25m, where 5 is the local boundary layer thickness. For this purpose, computational simulations have been carried out at Reynolds number Re 1350 based on the height of the conventional VG h 0.25m with the angle of attack of the vane to the oncoming flow β 18.5°. The results show that the VG scaling significantly affects the vortex trajectory and the peak vorticity generated by the primary vortex.