UCLA Extension

Theoretical and Computational Aeroelasticity

This course provides an in-depth treatment of the fundamental mechanisms behind various types of aircraft flutter instabilities and other aeroelastic phenomena. Both theoretical and computational methods of analysis are covered. Modern computational methods are used to study highly nonlinear aeroelastic problems of current interest, including transonic limit cycle flutter phenomena and flutter of flexible wings undergoing large deformations.

The course is intended for engineers and engineering managers involved in aeroelastic analysis, design, and testing of aerospace vehicles; and engineers in related disciplines, such as aerodynamics and controls, who seek a better understanding of flutter, divergence, and control reversal phenomena.

The goals of the course are to provide an up-to-date introduction to the classical theory as well as the modern computational methods based on FEM/CFD codes, provide participants with a working knowledge of flutter analysis techniques and the necessary theoretical foundation for understanding wind tunnel and flight test data, and discuss some of the unique aeroelastic challenges of emerging and future generations of air vehicles.

Course Materials

Lecture notes are distributed on the first day of the course. These notes are for participants only and are not for sale.

Coordinator and Lecturer

Oddvar O. Bendiksen, PhD, Professor, Department of Mechanical and Aerospace Engineering, Henry Samueli School of Engineering and Applied Science, UCLA. Professor Bendiksen’s main research interests are in the areas of aeroelasticity and unsteady aerodynamics. His expertise includes nonlinear transonic flutter, dynamic similarity and scaling laws, and computational aeroelasticity. He joined UCLA in 1988 and from 1994-1999 and again from 2005-2007 served as vice chairman of the department. From 1981-1988 he was an assistant professor of mechanical and aerospace engineering at Princeton University. Prior to his academic career, he spent 12 years in the aviation industry, including one year as director of engineering and three years as director of project engineering at Pacific Airmotive Corporation in Burbank, California.

Professor Bendiksen received the ASME Structures and Materials Award in 1990 and 1992 for pioneering research contributions in structural dynamics and computational aeroelasticity. He also was the 2004 recipient of the British Institution of Mechanical Engineers’ Thomas Hawksley Gold Medal and its Aerospace Industries Division’s Kenneth Harris James Prize, both in recognition of his work in computational aeroelasticity. Dr. Bendiksen is an Associate Editor of the Journal of Fluids and Structures and past associate editor of the AIAA Journal; an Associate Fellow of the AIAA; has consulted extensively in the aviation industry; and has lectured throughout the world on aeroelastic problems in aircraft and aircraft turbofan engines. He also was a World Class Visiting Scientist at the Air Force Research Laboratory at Wright-Patterson Air Force Base during the summers of 2006 through 2009.

Course Program

Introduction to Aeroelastic Problems in Aircraft

  • Historical overview
  • Importance in aircraft design

Static Aeroelasticity

  • Divergence of straight wings
  • Divergence of swept wings
  • Control surface effectiveness and aileron reversal
  • Effect of structural and aerodynamic nonlinearities

Unsteady Aerodynamics

  • Governing equations, small disturbance theory
  • Wings in incompressible flow, Theodorsen’s theory
  • Wings in subsonic flow, analytical and numerical solutions
  • Wings in supersonic flow, Mach cones, Rayleigh’s formula
  • Wings in transonic flow, shock waves, shock-boundary-layer interactions

Subsonic Flutter of Aircraft Wings

  • Typical section model
  • Bending-torsion flutter
  • Modal methods
  • Solution of aeroelastic equations
  • Physical mechanisms behind flutter

Panel Flutter

  • Supersonic panel flutter
  • Transonic panel flutter
  • Role of structural and aerodynamic nonlinearities

Computational Aeroelasticity

  • Structural finite element models
  • Computational Fluid Dynamics (CFD)
  • Fluid-structure coupling schemes
  • Computational solutions
  • Code verification and validation

Nonlinear Transonic Flutter and Divergence

  • Nonlinear nature of transonic flow
  • Transonic similarity rules for flutter and divergence
  • The transonic flutter boundary
  • Limit cycle oscillations (LCOs)
  • Control surface buzz

Aeroelastic Problems in Turbomachines

  • Supersonic flutter
  • Transonic flutter
  • Effect of blade mistuning

Control of Aeroelastic Instabilities

  • Control approaches based on aerodynamic control surfaces
  • Control approaches based on strain actuation (smart structures)
  • Aeroelastic mode energy diagrams

For more information contact the Short Course Program Office:
shortcourses@uclaextension.edu | (310) 825-3344 | fax (310) 206-2815

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