Turbulence Control Based on Reduced-Order Models and Nonlinear Control Design

We present a closed-loop flow control strategy for experiments and simulations. This strategy is based on low-order Galerkin models and nonlinear control. One key enabler is a partitioning of the flow in low-, dominant- and high-frequency components, i.e. a base flow, coherent structures and stochastic fluctuations. Another enabler is a control design exploiting the nonlinearities distilled by the model. Examples are presented for the actuated flow around a high-lift configuration and the controlled bluff body wake.

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