Experimental and numerical study of the aerodynamics of a cross flow fan embedded wing configuration

FanWing which was investigated in this study has a partially embedded cross flow fan (CFF) and is appropriate for low speed air vehicles that require high maneuverability. The aim of this study is to investigate experimentally and numerically the flow field around FanWing model and the effects of tip speed ratio (TSR) and Reynolds number (Re) parameters on aerodynamic forces acting on the model. In computational fluid dynamics (CFD) study, the Reynolds Averaged Navier-Stokes (RANS) model was solved for steady flow. In the wind tunnel, drag/thrust coefficients were obtained by pressure measurements in the wake of the model using the Jones method. Direct measurements of aerodynamic forces were performed on force-balance mechanism. Tufts method was used to investigate flow separation on the model surface. According to the experimental results TSR has more effect on the aerodynamic force coefficients comparing with Reynolds number and larger TSR increases the thrust and lift coefficients. While lift coefficient decreases with increasing Reynolds number, thrust coefficient increases. For the fan-off condition, flow separation was observed on model upper surface close to trailing edge at high angle of attack (alpha) and Re values which disappeared for the fan-on and TSR value over 1 condition. Thrust coefficients obtained by CFD analysis for alpha = 0 degrees, TSR = 1.4 and varying Reynolds numbers were within 12% of experimental results.