Abstract
Large eddy simulation is used to explore flow features and energy exchange physics between turbulent flow and structure vibration in the near-wall region with fluid–structure interaction (FSI). The statistical turbulence characteristics in the near-wall region of a vibrating wall, such as the skin frictional coefficient, velocity, pressure, vortices, and the coherent structures have been studied for an aerofoil blade passage of a true three-dimensional hydroturbine. The results show that (i) FSI greatly strengthens the turbulence in the inner region of y+ < 25; and (ii) the energy exchange mechanism between the flow and the vibration depends strongly on the vibration-induced vorticity in the inner region. The structural vibration provokes a frequent action between the low- and high-speed streaks to balance the energy deficit caused by the vibration. The velocity profile in the inner layer near the vibrating wall has a significant distinctness, and the viscosity effect of the fluid in the inner region decreases due to the vibration. The flow features in the inner layer are altered by a suitable wall vibration.
Original language | English |
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Pages (from-to) | 651-670 |
Number of pages | 20 |
Journal | International Journal of Modern Physics B |
Volume | 22 |
Issue number | 6 |
DOIs | |
Publication status | Published - 10 Mar 2008 |
Keywords
- turbulent flow
- turbulent boundary layer
- coherent structures
- large eddy simulation
- fluid structure interaction
- turbulent-boundary-layer
- drag reduction
- DNS
- oscillation
- passage