Intermittency of vorticity in a turbulent shear flow

Autocorrelations of squared velocity derivatives and squared vorticity fluctuation components have been measured at the centerline in the wake of a circular cylinder. Near the start of the inertial range, all the correlations exhibit similar power-law behaviors and yield essentially the same estimate of the intermittency exponent μ. The results imply that (∂u/∂x)² may be a reasonable substitute for the instantaneous dissipation rate of turbulent kinetic energy, for determining the value of μ.