REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

Steady-State Nonlinearity Compensation for Feedback Control of a Supersonic Blowdown Test Facility

biljana ilić

Military Technical Institute, Belgrade, biljana.ilic@icloud.com

mirko milosavljević

Military Technical Institute, Belgrade, mirko.milosavljevic.bgd@gmail.com

jovan isaković

Tehnikum Taurunum - School of Applied Engineering Studies, Belgrade, jovanisakovic@gmail.com

marko miloš

Faculty of Mechanical Engineering, University of Belgrade, mmilos@mas.bg.ac.rs

Abstract: The cost of control system development for a supersonic blowdown test facility is mainly due to expensive system integration that heavily relies on repeated testing and a complicated adjusting procedure for a range of operating conditions. By focusing on physical properties of the process, this paper proposes an approach for blowing pressure control that results in both improved accuracy and reduced tuning efforts. A dynamical model that reproduces the physical behavior of supersonic flow is presented first. Then a control strategy is designed, focusing on identifying and compensating the main nonlinearities. The suggested controller is tuned in simulations. Finally, experimental results obtained using the proposed control strategy are presented and discussed.

Keywords: Supersonic flow, nonlinearity, feedforward control, feedback control, blowdown test facility.