A decoupled fuzzy sliding-mode control for an aeroelastic system is derived. This aeroelastic dynamic system describes the nonlinear plunge and pitch motions of a wing section, using a single trailing-edge flap as the control input. The decoupled fuzzy sliding-mode control design method is proposed to simultaneously control both the plunge and pitch motions of the aeroelastic system. In this de...

The investigation of aeroelastic/aeroservoelastic stability through flight testing is an essential part of aircraft certification. The stability boundary prediction is especially difficult when the instability is associated with nonlinearities in the dynamics. An approach is presented for the characterization of the nonlinear dynamics by noniterative identification algorithms. Two different blo...

Active stabilisation of the 2 and 3 degrees-of-freedom (DoF) aeroelastic wind sections with structural nonlinearities led to various control solutions in the recent years. The paper proposes a control design strategy to stabilise the 3 Dof aeroelastic model. It is assumed that the aeroelastic model has uncertain parameters in the trailing edge dynamics and only one state variable, the pitch ang...

An integrated computational  uid dynamics (CFD) and computational structural dynamics (CSD) method is developed for the simulation and prediction of  utter. The CFD solver is based on an unsteady, parallel, multiblock, multigrid Ž nite volume algorithm for the Euler/Navier–Stokes equations. The CSD solver is based on the time integration of modal dynamic equations extracted from full Ž nite e...

This research combines Volterra theory and proper orthogonal decomposition (POD) into a hybrid methodology for reduced-order modeling of aeroelastic systems. The outcome of the method is a set of linear ordinary differential equations (ODEs) describing the modal amplitudes associated with both the structural modes and the POD basis functions for the fluid. For this research, the structural mode...

Our objective is to develop a nonlinear aerodynamic and nonlinear structural interaction (NANSI) methodology as an expedient aeroelastic tool to handle continuous dynamic motion of morphing vehicles/wings throughout the flight regimes of subsonic to transonic speeds. The proposed morph vehicles for method demonstration is the Lockheed Folding wing (the Folding wing). Preliminary results on Flut...

A new design concept in the development of vertical takeoff and landing aircraft with high forward flight speed capability is that of the X-Wing. The X-Wing is a stiff, bearingless helicopter rotor system which can be stopped in flight and the blades used as two forward-swept wings and two aft-swept wings. Because of the unusual configuration in the fixed-wing mode, there is a high potential fo...

A high-fidelity numerical formulation is presented for the high-speed aeroelastic behavior of slender composite wings. The compressible flow is modeled using the 3-D Euler equations on a deformable mesh, and an asymptotic approximation of the 3-D kinematically-nonlinear equations of elasticity models the anisotropic slender structure. The transfer of the distributed loads and displacements at t...

The development of a non-certainty-equivalent adaptive control system for the control of a nonlinear aeroelastic system is the subject of this paper. The prototypical aeroelastic wing section considered here includes structural nonlinearity and a single control surface for the purpose of control. Its dynamical model has two-degree-of-freedom and describes the plunge and pitch motion. It is assu...

This article proposes an efficient correction model that enables the extension of blade element momentum method (BEM) for swept blades. Standard BEM algorithms, assuming a straight in rotor plane, cannot account changes induction system introduced by sweep. The proposed corrects axial regarding two aspects: azimuthal displacement trailed vorticity and curved bound vortex on itself. extended alg...