VORTEX SHEDDING IN FLOW PAST AN INCLINED FLAT PLATE AT HIGH INCIDENCE

Dan Yang
Department of Marine Technology Norwegian University of Science and Technology, NO-7491 Trondheim, Norway

Bjornar Pettersen
Department of Marine Technology, Norwegian University of Science and Technology,NO-7491 Trondheim, Norway

Helge I. Andersson
Department of Energy and Process Engineering, Norwegian University of Science and Technology, Trondheim, Norway

Vagesh D. Narasimhamurthy
GexCon AS, P.O. Box 6015, Postterminalen, 5892 Bergen; Fluids Engineering Division, Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway

Аннотация

The properties of asymmetric wake pattern behind a flat plate inclined at angle of attack 20, 25 and 30 degrees are investigated. The Reynolds number based on the plate length is 1000. Both two-dimensional and three-dimensional calculations are performed by direct numerical simulation. The three-dimensional simulation is in better agreement with the experimental data. The asymmetric mean wake flow and coherent patterns in the three-dimensional simulations are also revealed by the time- and phase-averaged techniques and derived the turbulent properties. Unlike the symmetric wake flow, the vortices shed from the leading and trailing edges possess unequal strength. The vortices shed from the trailing edge possess higher strength. The three-dimensional simulation results compare very well with the experimental data.