Nonlinear Aeroservoelastic Analysis of Flexible Aircraft Described by Large Finite-Element Models

We present a nonlinear reduced-order formulation for the simulation of geometricallynonlinear responses of flexible aircraft and other aeroelastic systems. The method is based on a modal projection of the intrinsic description for beams coupled with a 2-D unsteady aerodynamic description. We also describe a method of obtaining coefficients of the nonlinear modal beam equations by means of a condensation process, based on the direct application of Guyan reduction of a high-fidelity 3D FE model. We then present structural and aeroelastic simulations and compare them against published results. Control design and closed-loop nonlinear simulations will also be demonstrated using the description in this work on a highly-flexible flying wing.

[1]  D. Peters.  Two-dimensional incompressible unsteady airfoil theory—An overview , 2008 .

[2]  Mark Drela,et al.  INTEGRATED SIMULATION MODEL FOR PRELIMINARY AERODYNAMIC, STRUCTURAL, AND CONTROL-LAW DESIGN OF AIRCRAFT , 1999 .

[3]  Silvestre T. Pinho,et al.  Homogenisation of slender periodic composite structures , 2012 .

[4]  Huibert Kwakernaak,et al.  Linear Optimal Control Systems , 1972 .

[5]  Henrik Hesse,et al.  Consistent structural linearisation in flexible-body dynamics with large rigid-body motion , 2012 .

[6]  M. Safonov,et al.  A Schur method for balanced-truncation model reduction , 1989 .

[7]  Bogdan I. Epureanu,et al.  An Intrinsic Description of the Nonlinear Aeroelasticity of Very Flexible Wings , 2011 .

[8]  Dewey H. Hodges,et al.  Geometrically Exact, Intrinsic Theory for Dynamics of Curved and Twisted Anisotropic Beams , 2004 .

[9]  Carlos E. S. Cesnik,et al.  Dynamic Response of Highly Flexible Flying Wings , 2011 .

[10]  Moshe Idan,et al.  Aeroservoelastic Structural and Control Optimization Using Robust Design Schemes , 2002 .

[11]  J. C. Simo,et al.  A three-dimensional finite-strain rod model. Part II: Computational aspects , 1986 .

[12]  Carlos E. S. Cesnik,et al.  Nonlinear Aeroelasticity and Flight Dynamics of High-Altitude Long-Endurance Aircraft , 2001 .

[13]  Yinan Wang,et al.  Robust Aeroelastic Control of Very Flexible Wings using Intrinsic Models , 2013 .

[14]  Eric L. Brown,et al.  Integrated strain actuation in aircraft with highly flexible composite wings , 2003 .

[15]  Carlos E. S. Cesnik,et al.  VABS: A New Concept for Composite Rotor Blade Cross-Sectional Modeling , 1995 .

[16]  Rafael Palacios,et al.  Nonlinear Model Reduction for Aeroelastic Control of Flexible Aircraft Described by Large Finite-Element Models , 2014 .

[17]  Paul J. Goulart,et al.  An Energy-Preserving Description of Nonlinear Beam Vibrations in Modal Coordinates , 2013 .

[18]  Dewey H. Hodges,et al.  Validation Studies for Aeroelastic Trim and Stability Analysis of Highly Flexible Aircraft , 2010 .

[19]  Joseba Murua,et al.  Applications of the unsteady vortex-lattice method in aircraft aeroelasticity and flight dynamics , 2012 .

[20]  Ilya Kolmanovsky,et al.  Gust Response Sensitivity Characteristics of Very Flexible Aircraft , 2012 .

[21]  Rafael Palacios,et al.  Nonlinear normal modes in an intrinsic theory of anisotropic beams , 2011 .

[22]  D. Naidu,et al.  Optimal Control Systems , 2018 .

[23]  Dewey H. Hodges,et al.  Flight Dynamics of Highly Flexible Flying Wings , 2006 .

[24]  R. Guyan.  Reduction of stiffness and mass matrices , 1965 .