2016 Fouatih OM, Madale M, Imine O, Imine B (2016) Design optimization of the aerodynamic passive flow control on NACA 4415 airfoil using vortex generators. , the use of VG is one of the simplest and most efficient boundary layer control techniques currently available, moreover, is usually the fastest and cheapest solution to control the flow ( Fouatih et al.
1950.Īccording to Manolesos and Voutsinas (2015) Manolesos M, Voutsinas SG (2015) Experimental investigation of the flow past passive vortex generators on an airfoil experiencing three-dimensional separation. Solid boundary surface for contact with a relatively moving fluid medium. Means of maintaining attached flow of a flow medium. Porto: Eurodyn., as well as revealed in the patent documents of Wheeler (1981) Wheeler GO, inventor Cessna Aircraft Co. In: Proceedings of the 9th International Conference on Structural Dynamics.
, Tebbiche and Boutoudj (2014) Tebbiche H, Boutoudj MS (2014) Optimized vortex generators in the flow separation control around a NACA 0015 profile. , 2005) Ashill PR, Fulker JL, Hackett KC (2005) A review of recent developments in flow control. In: 39th Aerospace Sciences Meeting and Exhibit. (2001 Ashill PR, Fulker JL, Hackett KC (2001) Research at DERA on sub boundary layer vortex generators (SBVGs). (1991) Lin J, Howard F, Selby G (1991) Exploratory study of vortex-generating devices for turbulent flow separation control. Several geometries have been studied as can be observed in the work of Lin et al.
There are many geometries and arrangements that can be applied to the VG, from rectangular, triangular, trapezoidal, to more complex geometries. , these vortices have a fundamental role in the control of the boundary layer, since they add momentum to the boundary layer, redirecting the high moment of external flow to regions near the surface, causing the boundary layer to overcome the resistance of the adverse pressure gradient, which in turn eliminates or retards the layer detachment point. Īre small fins or airfoils extended in the normal direction to the surface, being arranged with a slope relative to the direction of the flow.Īccording to Lin et al. One of the solutions found to delay the occurrence of this detachment is the vortex generators (VG), which for Lin (1999) Lin J (1999) Control of turbulent boundary-layer separation using micro-vortex generators. 2008 Gardarin B, Jacquin L, Geffroy P (2008) Flow separation control with vortex generator. The boundary layer represents a large part of the drag of an aircraft, and its separation consists of large loss of energy ( Gardarin et al. 1993 Kerho M, Hutcgerson S, Blacwelder RF, Liebeck RH (1993) Vortex generators used to control laminar separation bubbles. Many airfoils operating in Reynolds number as a function of wing chord length Re c <10 6 have a separation bubble at angles of attack smaller than the stall angle just after this bubble, a turbulent boundary layer is observed ( Kerho et al. >0), the boundary layer encounters resistance to its development, extending to the point where it detaches from the surface, generating a recirculation region (low pressure), which can increase body drag. When this gradient tends to be contrary to the flow direction (i.e. Currently, there is a great effort in the aeronautical industry focused on developing means to control the flow on the aircraft, seeking to improve its aerodynamic performance with the increase of the lift and maximum reduction of the drag on the structure.Īccording to Schlichting (1979), in low Reynolds (Re) numbers, curved surfaces are susceptible to the detachment of the boundary layer occurring mainly in curved bodies due to pressure distribution gradients.