Moosazadeh H, Ghadiri B, Zarifian P. Variable Thickness Supersonic Airfoil Post flutter With plunging and pitching free play and Non-linear Damping and Stiffness. Modares Mechanical Engineering 2015; 15 (6) :179-189
URL:
http://mme.modares.ac.ir/article-15-5930-en.html
1- Tarbiat Modares University
Abstract: (6134 Views)
The application of wing and stabilizer in aerospace vehicle is most important to stability and flight motion. Nonlinear 2D wing is estimated. Nonlinear damping and stiffness with freeplay in plunging and pitching motion is assumed. 2nd order Damping nonlinearity and 3rd order stiffness nonlinearity in pitching and plunging motion is assumed. Fully nonlinear structure with nonlinear 3rd order piston theory aerodynamic is assumed for the first time and result evaluated with different references. The equations are defined with Hamilton principle with the use of kinetic and potential energy and virtual work. They are solved in the state space via the ruge-kuta numerical method to determine chaotic and limit cycle oscillation motion of supersonic airfoil. The result show that as the speed increases, the behavior of 2D wing is softening type with the use of nonlinear rotational stiffness. But, It shows hardening type with the use of transversal nonlinear stiffness. The effect of transversal and rotational freeplay is more complicated than other parameters and increases instability in low speed. In other hand the stability increases with freeplay in high speed. As shown, increase velocity decrease damping effect in post flutter behavior.
Article Type:
Research Article |
Subject:
Aerospace Structures Received: 2014/12/29 | Accepted: 2015/02/25 | Published: 2015/04/25