Numerical And Experimental Investigation Of The Flow Around Airfoil For A Micro Fan-wing Aircraft

The fan-wing aircraft is a kind of new aircraft with excellent aerodynamic performance at low flying speed. The working principle of fan-wing aircraft is unique with a cross-flow fan embedded in the leading edge of a thick wing, which generates an eccentric vortex inside to provide lift force and thrust force for the aircraft. In this paper, the flow characteristics of a two dimensional fan-wing airfoil were studied by computational fluid dynamics method. Based on the single control variable method, double control variables method was used in this study to explore the optimizing methods of the aerodynamic performance of the airfoil, and verify the reliability of numerical calculation through experiments.The numerical simulation used the pressure-based solver with SIMPLE algorithm to predict the unsteady fan-wing flow, which was on the basis of 2D unstructured grid flow model, combined with the realizable k-ε turbulence model and enhanced wall function method. The relationships between the fan-wing flow characteristics and five single control variables were studied, including the cross-flow fan speed, the flow velocity, the wing’s front opening angle, the wing’s trailing edge angle and the wing’s length. On the basis, the matching relations of three pairs of variables were studied, including the fan speed and the flow velocity, the fan speed and the wing’s front opening angle, the wing’s trailing edge angle and the wing’s length. It is proved that the reasonable matching of fan-wing parameters can obtain better lift and thrust performances.