Calculations of the effects of blowing from the leading edges of a cambered delta wing

Abstract

The thin jet model applied by Spence to the study of the jet flap is combined with the vortex sheet model applied by Mangler and Smith to the study of leading-edge separation, to study the effect of blowing from the leading-edges of a cambered wing. The numerical techniques used to solve problems of leading-edge separation have been improved, and in the present investigation solutions have been generated for various values of the lift, camber and blowing strength of the jet whose direction is restricted to lie in a plane normal to the free stream. Regions existed in the parameter space within which solutions could not be obtained and there were regions within which solutions were not unique. The downward deflection of the jet which is associated with the camber does not produce a lift increment due to blowing which is significantly larger than the increment produced by the same blowing momentum on a plane wing. However, the drag for a given lift when blowing is introduced is greatly reduced, and in some cases a negative drag is predicted.