Active control of vortex-wall interactions
P. Koumoutsakos, Phys. Fluids, 9(12), 3808-3816, 1997
A new simple and efficient methodology is presented for the active control of vortical wall bounded flows. The method is based on sensing of the wall pressure and the calculation of the wall vorticity flux. This information is used to determine explicitly the amount of unsteady, spatially varying mass transpiration, used as an actuating mechanism, necessary to achieve a desired wall vorticity flux. The present scheme is based on the physical mechanism of vorticity generation at solid boundaries. It has the advantage of implementing quantities that can be measured and manipulated at the wall, in computations as well as in experiments. It is shown to reproduce efficiently phenomena previously attained using off-wall information. An active control methodology is outlined and the practical implementation of the present scheme is discussed. (C) 1997 American Institute of Physics. [S1070-6631(97)03712-4].