Flow field and energy balance according to the spatial linear stability theory of the Blasius boundary layer.

In search of physical processes which control the boundary-layer instability, instantaneous streamlines and instantaneous total vorticity fields have been mapped out. One of the purposes of these demonstrations is to dispel a widespread myth that a voriticity maximum is attached to the critical layer. There is, however, a simple and potentially important mechanism by which the total vorticity peaks appear inside the flow field. Based upon the energy equations for the spatial stability analyses, contributing terms have been evaluated. It is particularly emphasized that the damping is primarily due to the negative energy production by the Reynolds stress rather than the viscous dissipation. Moveover, the pressure-velocity correlation term is found to have significant contributions to the energy balance. (A)