Flutter analysis of fixed and rotary wings

Download

index.pdf

Date

2019

Author

Çiçek, Orhun

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

350
views

203
downloads

Flutter is a critical stability problem that needs to be considered for the design of fixed and rotary wings. Although flutter susceptibility is addressed during the test phases of the most of the aircraft, an analytical model is required for the determination of flutter boundaries and most importantly for supplying feedback to the design procedure in order to have a structure that is free from flutter. In this thesis, several flutter analysis methodologies are investigated for both fixed and rotary wing structures. For the analytical models, a theoretical background is given for Theodorsen, Loewy, Wagner unsteady aerodynamic theories and Pitt-Peters and Peters-He inflow theories. In addition, derivation of the simple beam theory is explained with the expansion methods of Rayleigh-Ritz and Galerkin. Three different solution types; k-method, modified k-method and p-method are studied based on the aerodynamic theory implemented. The flutter analysis results are verified and compared with the results given in the literature. The fixed wing analyses are validated with Goland’s fixed wing results, rotary wing analyses are validated both with helicopter blade and wind turbine blade analyses results. Case studies are performed to investigate the effects of the shear center and center of gravity locations and the forward velocity of the helicopter on the flutter analysis results.

Subject Keywords

Flutter (Aerodynamics)., Keywords: Flutter, Stability, Unsteady Aerodynamics, Dynamic Inflow, RayleighRitz Method.

URI

http://etd.lib.metu.edu.tr/upload/12623371/index.pdf
https://hdl.handle.net/11511/43588

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Aeroservoelastic analysis and robust controller synthesis for flutter suppression of air vehicle control actuation systems Akmeşe, Alper; Platin, Bülent Emre; Department of Mechanical Engineering (2006) Flutter is one of the most important phenomena in which aerodynamic surfaces become unstable in certain flight conditions. Since the 1930’s many studies were conducted in the areas of flutter prediction in design stage, research of design methods for flutter prevention, derivation and confirmation of flutter flight envelopes via tests, and in similar subjects for aircraft wings. With the use of controllers in 1960’s, studies on the active flutter suppression began. First the classical controllers were used....
Flutter analysis and simulated flutter test of wings Balevi, Taner Birtan; Kayran, Altan; Department of Aerospace Engineering (2012) Flutter is a dynamic instability which can result in catastrophic failures of an air vehicle. Preventing flutter can be an important factor in the aircraft design, affecting the structural design. Thus, the weight and performance of the aircraft is also being affected. Understanding the role of each design factor of a wing on the onset of flutter can help designers on the flutter clearance of the aircraft. Analysis to predict flutter, ground vibration tests and flight flutter tests, which are performed to v...
Vortex flow aerodynamics behind a symmetric airfoil at low angles of attack and Reynolds numbers Kurtuluş, Dilek Funda (2021-11-01) The low Reynolds number aerodynamics is important to investigate for micro air vehicle applications. The current paper covers numerical simulations to present the downstream development of the wake patterns and detailed analysis of the vortices generated at the downstream of NACA 0012 airfoil around the critical angle of attack where the instantaneous vortex patterns are oscillatory and differ from the mean vortex pattern for low Reynolds numbers ranging from 1000 to 4000. The instantaneous and mean aerodyn...
Aeroservoelastic Modelling and Analysis of a Missile Control Surface with a Nonlinear Electromechanical Actuator Mehmet Ozan, Nalcı; Kayran, Altan (null; 2014-06-16) In this study, aeroservoelastic modeling and analysis of a missile control surface which is operated and controlled by a power limited, nonlinear electromechanical actuator is performed. Linear models of the control fin structure and aerodynamics together with the nonlinear servo-actuation system are built and integrated. The resulting aeroservoelastic system is analyzed both in time and frequency domain. Structural model of the control fin is based on the finite element model of the fin. Aerodynamic model ...
Generic trim analysis and simulation algorithm creation for design and optimization of the fixed wing aircraft Özdemir, Mustafa; Kurtuluş, Dilek Funda (2021-09-10) In order to design a fixed wing aircraft, certain phases are needed to perform. From these phases, trim analysis and simulation are very crucial for design process. Trim and simulation analysis enable to calculate performance and stability characteristics of the aircraft. After aerodynamic, weight and engine database creation, the next step is trim analysis and simulations. However, database creation phase requires a huge amount of computing time, and for the preliminary design phase it is needed to perform...

Citation Formats

O. Çiçek, “Flutter analysis of fixed and rotary wings,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Aerospace Engineering., Middle East Technical University, 2019.