TY - JOUR
T1 - Development and Application of a Reduced Order Model for the Control of Self-Sustained Instabilities in Cavity Flows
AU - Kaushik Kumar Nagarajan, Laurent Cordier & Christophe Airiau
JO - Communications in Computational Physics
VL - 1
SP - 186
EP - 218
PY - 2014
DA - 2014/07
SN - 14
DO - http://doi.org/10.4208/cicp.300112.100812a
UR - https://global-sci.org/intro/article_detail/cicp/7156.html
KW - 
AB - <p style="text-align: justify;">Flow around a cavity is characterized by a self-sustained mechanism in
which the shear layer impinges on the downstream edge of the cavity resulting in
a feedback mechanism. Direct Numerical Simulations of the flow at low Reynolds
number has been carried out to get pressure and velocity fluctuations, for the case of
un-actuated and multi frequency actuation. A Reduced Order Model for the isentropic
compressible equations based on the method of Proper Orthogonal Decomposition has
been constructed. The model has been extended to include the effect of control. The
Reduced Order dynamical system shows a divergence in time integration. A method
of calibration based on the minimization of a linear functional of error, to the sensitivity
of the modes, is proposed. The calibrated low order model is used to design a feedback
control of cavity flows based on an observer design. For the experimental implementation of the controller, a state estimate based on the observed pressure measurements
is obtained through a linear stochastic estimation. Finally the obtained control is introduced into the Direct Numerical Simulation to obtain a decrease in spectra of the
cavity acoustic mode.</p>