Integrated Structural, Flight Dynamics and Aeroelastic Analysis of the ANCE X-3d as a Flexible Body

Abstract

The objective of this paper is to generate simplified structural configurations for the ANCE X-3d by considering the influence of structural flexibility on the flight dynamic characteristics and the aeroelastic phenomena. This aircraft consists of an unswept wing with double tail boom structure and two vertical stabilizers. Two structures were designed by an analytical approach and finite element models to create suitable structural arrangements for the wing, tail booms, and stabilizers, and carbon-fiber composite materials were selected for this purpose. Knowing the stiffness and mass properties of the main structural components, reduced order aero-structural models were developed to quantify the influence of the flexibility on the aircraft aerodynamics and stability characteristics. Flight dynamic evaluation of the airplane considering the flexibility of the structure was performed at different velocities and altitudes. The resultant flutter and divergence velocities fulfill the design criteria. Nomenclature Ak = circulation Fourier mode coefficients CD0 = minimum drag coefficient CL0, CM0 = lift and pitching moment coefficients at zero angle of attack CLq, CDq, CMq = variation of lift, drag, and pitching moment coefficients with pitch rate CLα, CDα, CMα = lift, drag, and pitching moment slopes CYβ, Cℓβ, Cnβ = variation of side force, rolling, yawing coefficients with sideslip angle CYp, Cℓp, Cnp = variation of side force, rolling, yawing coefficients with roll rate CYr, Cℓr, Cnr = variation of side force, rolling, yawing coefficients with yaw rate D = control state vector E = control error-integral vector E = young modulus, Pa EI = bending stiffness, Nm 2