Vorticity measurements in turbulent grid flows

Abstract

Results of direct simultaneous measurements of vorticity and velocity are reported for a turbulent flow past a grid of air and (slightly salted) water by two qualitatively different methods. Both experiments were preformed in the same geometry and at the same Taylor microscale Reynolds number ~75. The experiments with salted water flow were performed in water tunnel of the laboratory for vorticity-helicity studiesx Faculty of Engineering, Tel-Aviv University and the experiments with air flow were performed in the wind tunnel of the Turbulent Flow Laboratory, University of Maryland. One of the most striking results is that in both experiments the flow is found to lack reflexional symmetry.