Abstract:

A three-dimensional nonlinear method for determining the aerodynamic performance of a jet flap wing has been developed. The method utilizes a system of bound and free vortices with vortex lattices to represent the wing, jetwake and tip vortices. The kinematic boundary conditions are satisfied at the wing, as the ordinary vortex lattice theory states. But the feature of the present method lies in satisfaction of both kinematic and dynamic conditions and consideration of vortex interaction. The solutions obtained include chordwise and spanwise load distributions, from which sectional and total aerodynamic quantities are derived. In the solution the jet-wake sheet and the tip vortex shape are determined simultaneously with the nonlinear effects taken into account. The solutions obtained by the present method agree well with other analytical results and available data for a jet wing with large aspect ratio. The present method has no limitation on the aspect ratio and is applicable to the cases with large jet blowing angles as well. The partial span jet blowing and the disturbance of main wing blowing to the second wing are also treated in this ptaper.