抄録
This study investigates active control of self-sustained oscillating flow past an open cavity by a moving bottom wall. The incompressible Navier-Stokes equations are solved using finite difference methods for the two-dimensional cavity with laminar boundary layer upstream. We move the cavity bottom wall tangentially with nondimensional velocity ranging from -0.2 to +0.2. The computational results show that the effect of wall velocity changes the characteristics of recirculating flow in the cavity and that the modification of recirculating flow plays an important role in changing the oscillation characteristics of the separated shear layer. When the wall velocity is less than -0.1, two recirculating vortices change to one clockwise recirculating vortex in the cavity, so that the self-excited shear layer oscillations are completely suppressed. When the wall velocity is more than +0.19, the two stationary vortices exist in the upper side and lower side of cavity respectively and the self-excited oscillations are suppressed.
