Numerical investigations of the interaction between strake vortices and a two-element airfoil

Numerical investigations, using the Large Eddy Simulation approach, of the interaction between streamwise vortices and a high-lift two-element airfoil system are made. A delta wing upstream of the two-element airfoil generates two vortices, which move downstream over the suction and pressure sides of the high-lift arrangement and into the near-wake while interacting with the local flowfield. The vortices have characteristics which resemble those of a nacelle strake vortex but scaled to suit the airfoil dimensions. Calculations, of the static pressure distributions, with and without the delta wing present, are made to show the effect of the vortices on the characteristics of the high-lift arrangement. The development of the vortex with downstream distance is validated and calculations are made for several vertical offsets of the delta wing relative to the main airfoil position. It is found that there is a marked influence of the vortices on the flowfield over the high-lift arrangement and regarding the lift and drag coefficients of the two-element airfoil system.