Numerical Investigation of the Evolution of Disturbances in Supersonic Sharp Cone Boundary Layers

The spatial evolution of 2_D disturbances in supersonic sharp cone boundary layers was investigated by direct numerical simulation(DNS)in high order compact difference scheme.The results obtained suggested that although the normal velocity in the sharp cone boundary layer is not small, the evolution of amplitude and phase for small amplitude disturbances would be well in accord with the results obtained by the linear stability theory(LST)which supposes the flow is parallel.The evolution of some finite amplitude disturbances was also investigated,and the characteristic of the evolution was shown.And shocklets were also found when the amplitude of the disturbances over some value.