Statistical properties of the interface in the turbulent wake of a heated cylinder

The statistical properties of the interface between turbulent and nonturbulent fluid in the two-dimensional wake of a heated cylinder are presented. The following are the principal results: distributions of the intermittency factor and crossing frequency; probability density functions of the durations of the passages of turbulent and nonturbulent fluid, indicating that the longer durations are exponentially distributed; the mean and rms slope angles of the interface at upstream and downstream edges, showing an asymmetry of the mean shape with a steeper downstream edge; and the relative number of overhangs at the two sets of edges, namely, 25% at the downstream edge and only 6% at the upstream edge.