Turbulence properties of an axisymmetric separation-and-reattaching flow

The time-mean and root-mean-squared values, the integral time scale, the phase velocity, and the longitudinal and circumferential length scales of the velocity and the surface-pressure fluctuations are presented for a separation-and-reattaching flow formed by the boundary-layer separation at the leading edge of a blunt circular cylinder at Reynolds numbers of the order of 100,000. The cross correlations of the surface-pressure fluctuations suggested that the flow in the reattachment region of the separated shear layer has a cellular structure. A phase-averaging measurement of the reverse-flow intermittency revealed an aspect of the spatial extent of the flow unsteadiness in the reattachment region.