Experimental Development of a Reduced-Order Model for Flow Separation Control

Practical methods to enable control of turbulent ∞ows in a closed-loop sense are developed with a direct application in this case to ∞ow separation control over an airfoil. The tools used to reduce the dimension and complexity of the problems are based on the Proper Orthogonal Decomposition (POD) and on measurement algorithms derived from the Linear Stochastic Estimation (LSE). Signiflcant progress has been made in the measurement techniques that enable a practical estimation of an entire velocity fleld from surface pressure measurements. This in turn, permits a more accurate representation of the system when developing dynamical systems based on experimental data. The ultimate goal is to derive a plant that accurately represents the ∞ow dynamics and that contains an actuation input explicitly.

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