EFFECT OF VORTEX BREAKDOWN ON LATERAL AERODYNAMIC COEFFICIENTS OF A MANEUVERABLE AIRCRAFT MODEL

摘要

A numerical study of the lateral aerodynamic characteristics of a maneuverable aircraft model at high angles of attack in a wide range of slip angles has been carried out. It is shown that at zero sideslip angle intensive vortices are generated from the forebody of the model and the outer wing panels. The vortices lose their stability when the angle of attack is increased and then break down. The vortex breakdown points are displaced in an upward flow direction. At sideslip the breakdown of vortices from the windward and leeward sides of the lifting surface becomes asymmetric and strongly influences the lateral aerodynamic coefficients of the model such that it leads to lateral instability, which is related to the change in the effective leading edge sweep angles. The results of the computations are in satisfactory agreement with the experimental data obtained during testing in the T-102 wind tunnel.