Applications of the unsteady vortex-lattice method in aircraft aeroelasticity and flight dynamics

Murua, Joseba; Palacios, Rafael; Graham, J. M. R.

doi:10.1016/j.paerosci.2012.06.001

Cited by 234 publications

(183 citation statements)

References 147 publications

Supporting

Mentioning

181

Contrasting

Order By: Relevance

“…This linear, secondorder set of ODEs is then discretized in time using the Newmark-β scheme and cast in state-space form and coupled with a linearized UVLM aerodynamics model. A linearized form of the aerodynamics model is constructed using the model developed by Murua et al 23 and based on the description by Hall. 24 To obtain the state-space form of the UVLM, the governing equations are linearized on a frozen aerodynamic geometry around the aircraft trim condition, which may include large wing deformations and a non-planar wake.…”

Section: Iib Linearizationmentioning

confidence: 99%

See 1 more Smart Citation

Integrated Flight Dynamics and Aeroelasticity of Flexible Aircraft with Application to Swept Flying Wings

Simpson

Palacios

Goulart

2015

56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference

Self Cite

View full text Add to dashboard Cite

The dynamics of flexible, swept flying wing (SFW) aircraft are described by a set of nonlinear, multi-disciplinary equations of motion. Aircraft structures are modeled using a geometrically-exact composite beam model which can, in general, capture large dynamic deformations and the interaction between rigid-body and elastic degrees-offreedom. In addition, an implementation of the unsteady vortex-lattice method capable of handling arbitrary kinematics is used to capture the unsteady, three-dimensional flow-field around the aircraft as it deforms. Linearization of this coupled nonlinear description, which can in general be around a nonlinear equilibrium, is performed to yield linear time-invariant state-space models. Verification of aeroelastic stability analyses using these models is carried out. Subsequently, a set of SFW models are developed and the dynamic stability characteristics of these aircraft are investigated for a range of flight velocities and vehicle parameters. Nomenclature

show abstract

Section: Iib Linearizationmentioning

confidence: 99%

“…23 This set of coupled, linear EoM now form a suitable basis for stability analyses, model reduction, and control syntheses.…”

Section: Iib Linearizationmentioning

confidence: 99%

Integrated Flight Dynamics and Aeroelasticity of Flexible Aircraft with Application to Swept Flying Wings

Simpson

Palacios

Goulart

2015

56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference

Self Cite

View full text Add to dashboard Cite

show abstract

“…To obtain the state-space form of the UVLM, the governing equations are linearized on a frozen aerodynamic geometry. 20,31 They are naturally written in a descriptor state-space form as…”

Section: Iiib Monolithic Description Of Linearized Flexible-aircrafmentioning

confidence: 99%

Consistent Structural Linearization in Flexible Aircraft Dynamics with Large Rigid-Body Motion

2014

Self Cite

View full text Add to dashboard Cite

This paper investigates the linearization, using perturbation methods, of the structural deformations in the nonlinear flight dynamic response of aircraft with slender, flexible wings. The starting point is the coupling of a displacement-based geometrically nonlinear flexible-body dynamics formulation with a 3D unsteady vortex lattice method. This is followed by a linearization of the structural degrees of freedom, which are assumed to be small in a body-fixed reference frame. The translations and rotations of that reference frame and their time derivatives, which describe the vehicle flight dynamics, can still be arbitrarily large. The resulting system preserves all couplings between rigid and elastic motions and can be projected

show abstract

“…3 A number of integrated simulation frameworks have been constructed to model the nonlinear response to gust loads of very flexible aircraft. [4][5][6][7][8][9] They have provided substantial evidence of the importance of modelling large, geometrically-nonlinear deflections, and the challenges associated to the development of control systems for gust alleviation and trajectory tracking in such systems. Cook et al 10 and Dillsaver et al 11 applied H ∞ and LQG controllers respectively to full aircraft models and investigated the response to gust and continuous disturbances.…”

Section: Introductionmentioning

confidence: 99%

Robust Aeroelastic Control of Very Flexible Wings using Intrinsic Models

Wang

Wynn

Palacios

2013

54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference

Self Cite

View full text Add to dashboard Cite

This paper explores the robust control of large flexible wings when their dynamics are written in terms of intrinsic variables, that is, velocities and stress resultants. Assuming 2-D strip theory for the aerodynamics, the resulting nonlinear aeroelastic equations of motion are written in modal coordinates. It is seen that a system which experiences large displacements can nonetheless be accurately described by a system with only weak nonlinear couplings in this description of the wing dynamics. As result, a linear robust controller acting on a control surface is able to effectively provide gust load alleviation and flutter suppression even when the wing structure undergoes large deformations. This is numerically demonstrated on various representative test cases.

show abstract

Applications of the unsteady vortex-lattice method in aircraft aeroelasticity and flight dynamics

Cited by 234 publications

References 147 publications

Integrated Flight Dynamics and Aeroelasticity of Flexible Aircraft with Application to Swept Flying Wings

Integrated Flight Dynamics and Aeroelasticity of Flexible Aircraft with Application to Swept Flying Wings

Consistent Structural Linearization in Flexible Aircraft Dynamics with Large Rigid-Body Motion

Robust Aeroelastic Control of Very Flexible Wings using Intrinsic Models

Contact Info

Product

Resources

About