Adaptive Identification and Control of Flow-Induced Cavity Oscillations

Progress towards an adaptive self-tuning regulator (STR) for the cavity tone problem is discussed in this paper. Adaptive system identification algorithms were applied to an experimental cavity-flow tested as a prerequisite to control. In addition, a simple digital controller and a piezoelectric bimorph actuator were used to demonstrate multiple tone suppression. The control tests at Mach numbers of 0.275, 0.40, and 0.60 indicated approx. = 7dB tone reductions at multiple frequencies. Several different adaptive system identification algorithms were applied at a single freestream Mach number of 0.275. Adaptive finite-impulse response (FIR) filters of orders up to N = 100 were found to be unsuitable for modeling the cavity flow dynamics. Adaptive infinite-impulse response (IIR) filters of comparable order better captured the system dynamics. Two recursive algorithms, the least-mean square (LMS) and the recursive-least square (RLS), were utilized to update the adaptive filter coefficients. Given the sample-time requirements imposed by the cavity flow dynamics, the computational simplicity of the least mean squares (LMS) algorithm is advantageous for real-time control.

[1]  Howard Jay Chizeck,et al.  Closed Loop Control , 1985 .

[2]  David R. Williams,et al.  Experiments on controlling multiple acoustic modes in cavities , 2000 .

[3]  David Williams,et al.  Closed-Loop Control in Cavities with Unsteady Bleed Forcing , 2000 .

[4]  David Williams,et al.  Adaptive control of multiple acoustic modes in cavities , 2001 .

[5]  Andrew J. Kurdila,et al.  Modeling and Design of Piezoelectric Actuators for Fluid Flow Control , 2000 .

[6]  Deepak Shukla,et al.  DEVELOPMENT OF AN ADAPTIVE WEAPONS-BAY SUPPRESSION SYSTEM , 1999 .

[7]  David E. Cox,et al.  Experimental Feedback Control of Flow-Induced Cavity Tones , 2002 .

[8]  Sanjay Garg,et al.  Development of Piezoelectric Actuators for Active Flow Control , 2001 .

[9]  Petre Stoica,et al.  Decentralized Control , 2018, The Control Systems Handbook.

[10]  Louis N. Cattafesta,et al.  Experiments on compressible flow-induced cavity oscillations , 1998 .

[11]  Kimon Roussopoulos,et al.  Feedback control of vortex shedding at low Reynolds numbers , 1993, Journal of Fluid Mechanics.

[12]  Samir Ziada,et al.  Feedback Control of Globally Unstable Flows: Impinging Shear Flows , 1995 .

[13]  Clarence W. Rowley,et al.  MODEL-BASED CONTROL OF CAVITY OSCILLATIONS, PART II: SYSTEM IDENTIFICATION AND ANALYSIS , 2002 .

[14]  Louis N. Cattafesta,et al.  Active Control of Flow-Induced Cavity Resonance , 1997 .

[15]  J. Shynk Adaptive IIR filtering , 1989, IEEE ASSP Magazine.

[16]  E. Covert,et al.  Flow-Induced Pressure Oscillations in Shallow Cavities , 1971 .