# Theoretical models of flow control in near-wall areas

## Abstract

We present a non-linear near-wall flows control algorithm. This algorithm uses captured vortices in the cross grooves and fluid ejection. The controller is based on a model of point vortices with one degree of freedom and consists of the equation of vortex equilibrium and the Kutta condition in the groove edges. Parameters of a control system for grooves of different depths in a stationary stream are calculated. We determined that in shallow grooves, the region of stability of vortices is wider, than in deep grooves, so they are more promising for control. These results are used to estimate the parameters of the active control scheme with a feedback in a nonstationary flow when the system is responsive to external perturbations. Examples of an implementation of such a scheme are presented for the case when the flow velocity changes periodically or linearly.## References

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