Development of Aeroelastic and Aeroservoelastic Reduced Order Models for Active Structural Control

Abstract

In this paper, we present a holistic methodology and framework that uniquely integrates the aerodynamics reduced order model (ROM), structural dynamics model, and active structural control into a single platform to enable integrated, ultra-fast ROMs for efficient Aeroelastic (AE) and Aeroservoelastic (ASE) analysis, and controller design. The aerodynamic ROM (AeroROM) was developed based on the system identification approach to establish the mapping relationship between the structural displacement and the Generalized Aerodynamic Force, and hence, could be used to accurately predict aerodynamic response at various flight conditions. The AeroROM was then coupled with a rigid-body dynamics model by virtue of appropriate sensors, actuators, and control laws to form an integrated ASE ROM for closed-loop simulation and analysis. Several case studies using 2 DOF rigid body (pitch-plunge motion) and 3 DOF (pitch-plunge-flap motion) airfoil in conjunction with control laws and at different flight conditions were performed. The case studies demonstrate that the integrated ROM can be used for accurate AE and ASE analysis. The ROM results show excellent agreement with high-fidelity CFD-CSD simulations (<1% relative error), but at significantly reduced computational cost (typically 10,000× speedup). The results also demonstrate that the nonlinear response at the transonic regime can be accurately captured by the developed ROM.