C.E.S. Cesnik, W. Su

This paper focuses on effectively modeling the nonlinear aeroelastic behavior of fully flexible aircraft for preliminary design. The study is conducted based on a nonlinear strained-based finite element framework in which the developed low-order formulation captures the nonlinear (large) deflection behavior of the wings, and the unsteady subsonic aerodynamic forces acting on them. Instead of merely considering the nonlinearity of the wings, the paper will allow all members of the vehicle to be flexible. Due to their characteristics of being long and slender structures, the wings, tail, and fuselage of the fully flexible aircraft can be modeled as beams undergoing three dimensional displacements and rotations. The cross-sectional stiffness and inertia properties of the beams are calculated along the span, and then incorporated into the 1-D nonlinear beam model. Finite-state unsteady subsonic aerodynamic loads are coupled with all lifting surfaces, so as to complete the state space aeroelastic model. Two different vehicle configurations are modeled and studied, that is, a conventional single-wing and a joined-wing aircraft with flexible fuselage and tail. Based on the proposed models, static and dynamic stabilities are studied and compared with rigidized, linearized, and/or nonlinear models.

International Forum on Aeroelasticity and Structural Dynamics, 2005, München

Conference Paper

englisch

21,0 x 29,7 cm, 22 Seiten

DGLR-Bericht, 2005, 2005-04, International Forum on Aeroelasticity and Structural Dynamics 2005; S.1-22; 2005; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

in getr. Zählung;

aeroelasticity, nonlinearity

Bibliothek

2005