Retrospective Cost Adaptive Flow Control Using a Dielectric Barrier Discharge Actuator

Abstract

Retrospective cost adaptive control is applied to low Reynolds number aerodynamics around an SD7003 airfoil with a dielectric barrier discharge (DBD) actuator located near the leading edge. The adaptive control algorithm uses knowledge of Markov parameters to capture information about any nonminimum-phase zeros in the dynamics. In this paper, we explore the impact of the adaptive controller on the aerodynamics under the chord Reynolds numbers of 300 and 60,000, and with both steady and unsteady free-stream conditions. By varying the voltage to the DBD actuator, effective control of unsteady flow structure can be performed to decrease drag and increase lift. Nomenclature E Electric field vector F avg Quasi-steady body force from the DBD actuator F 1 , F 2 Body forces in the x 1 and x 2 directions q i Electric charge of a species n i Particle number density of a species ρ c Net charge density q c Unit electric charge (= 1.6 × 10 −19 C) c Chord length of airfoil U Free stream velocity C l Lift coefficient of an airfoil, which is the integral over the surface of the airfoil of the normalized pressure force in the direction of lift C d Drag coefficient of an airfoil, which is the integral over the surface of the airfoil of the normalized pressure force in the direction of drag V app Voltage applied to the DBD actuator U t/c Normalized time in the flow simulation Re Reynolds number * Graduate student, AIAA Student Member.

Retrospective‐cost‐based adaptive model refinement for the ionosphere and thermosphere

“…Although the techniques developed in refs [23,24] apply to linear systems, this paper shows that model refinement based on RCAC can be effective for large‐scale nonlinear systems such as GITM. Additional relevant literature on retrospective cost optimization includes refs [27–34].…”

Retrospective Cost Adaptive Control of Low-Reynolds Number Aerodynamics Using a Dielectric Barrier Discharge Actuator

“…Adaptive control techniques have the advantage of tuning the feedback gains in response to the true plant dynamics and exogenous signals. Nevertheless, these techniques typically require some model information, for example, reduced order models 9 or time-series models 10 , and identifying this model information from highdimensional flow fields can be challenging. More information about identifying time-series flow models can be found in Ref.…”

“…11 and Ref. 12. In previous work 10 , the retrospective cost adaptive control (RCAC) algorithm was applied to control the pressure drag of the SD 7003 airfoil at a Reynolds number of 300. RCAC updates the control parameters based on the retrospective performance, which is a surrogate measure of the true performance.…”

Retrospective Cost Adaptive Flow Control Using a Dielectric Barrier Discharge Actuator with Parameter-Dependent Modeling

“…Adaptive control techniques have the advantage of tuning the feedback gains in response to the true plant dynamics and exogenous signals. Nevertheless, these techniques typically require some model information, for example, reduced-order models 10 and discrete time-series models 11 , and identifying this model information can be challenging.…”