Stability of vortex pairs over slender conical bodies - Theory and numerical computations

Abstract

Theoretical analyses and computational fluid dynamics (CFD) simulations are presented to study the formation and stability of stationary symmetric and asymmetric vortex pairs over slender conical bodies in an inviscid incompressible flow at high angles of attack with and without sideslip. The theoretical analysis is based on an eigenvalue analysis on the motion of the vortices under small perturbations. A three-dimensional time-accurate Euler code is used to compute five typical flows studied by the theoretical method on extraordinarily fine and overset grids with strict convergence criteria. The computational results agree well with the theoretical predictions and corroborate on the conclusion that an absolute type of hydrodynamic instability can be the mechanism for breaking of symmetry of the vortex flow over slender conical bodies at high angles of attack. The presented results demonstrate the usefulness of CFD for stability studies of vortex flow? over slender bodies at high angles of attack.