Computational study of passive control of flow separation with vortex generators

The Separation control has received a considerable amount of focus due to aerodynamic and automobile industries. Flow separation leads to increase in drag and energy losses and so on. In adverse pressure gradient, flow separation is very usual phenomena, and the control of flow separation is compulsory to achieve higher efficiency. Vortex Generators (VGs) are commonly used devices to control flow separation. In this research-work flow separation in turbulent boundary layer has been studied on the plate with adverse pressure gradient and then it is explored to a symmetric and an asymmetric airfoil. The Spalart-Allmaras model is used to model the Reynold’s stress. The effect of various parameters of vortex generator on separation has been studied. Those parameters are shape, orientation, position and height of vortex generators. Optimization of all those parameters has been studied using CFD simulations in order to delay boundary layer flow separation and reduce pressure drag on the surface with adverse pressure gradient. The separation is delayed by 60% in plate with adverse pressure gradient and 40% and 27% drag force is delayed by a symmetric and an asymmetric airfoil respectively. Finally, it is concluded that this design of vortex generator in this computational study can be useful in engineering application.