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Memorias de investigación
Communications at congresses:
Flutter Amplitude Saturation by Nonlinear Friction Forces: An Asymptotic Approach
Year:2013
Research Areas
  • Aeronautical engineering,
  • Turbomachinery
Information
Abstract
The computation of the friction saturated vibratory response of an aerodynamically unstable bladed-disk in a realistic configuration is a formidable numerical task, even for the simplified case of assuming the aerodynamic forces to be linear. The non-linear friction forces effectively couple different traveling waves modes and, in order to properly capture the dynamics of the system, large time simulations are typically required to reach a final, saturated state. Despite of all the above complications, the output of the system (in the friction microslip regime) is not that complex: it typically consists of a superposition of the aeroelastic unstable traveling waves, which oscillate at the elastic modal frequency and exhibit also a modulation in a much longer time scale. This large time modulation over the purely elastic oscillation is due to both, the small aerodynamic effects and the small nonlinear friction forces. The correct computation of these two small effects (small as compared with the elastic forces) is crucial to determine the final amplitude of the flutter vibration, which basically results from its balance. In this work we apply asymptotic techniques to obtain a new simplified model that gives only the slow time dynamics of the amplitudes of the traveling waves, filtering out the fast elastic oscillation. The resulting asymptotic model is very reduced and extremely cheap to simulate, and it has the advantage that it gives precise information about how the nonlinear friction at the fir-tree actually acts in the process of saturation of the vibration amplitude.
International
Si
Congress
ASME Turbo Expo 2013
960
Place
San Antonio, Texas, USA
Reviewers
Si
ISBN/ISSN
978-0-7918-5527-0
Start Date
03/06/2013
End Date
07/06/2013
From page
1
To page
9
ASME Turbo Expo 2013: Turbine Technical Conference and Exposition
Participants
  • Autor: Carlos Martel Escobar (UPM)
  • Autor: Roque Corral Garcia (UPM)
Research Group, Departaments and Institutes related
  • Creador: Grupo de Investigación: Mecánica de Fluidos Computacional
  • Grupo de Investigación: Dinámica y estabilidad no lineal en ingeniería aeroespacial
  • Departamento: Fundamentos Matemáticos de la Tecnología Aeronáutica
  • Departamento: Motopropulsión y Termofluidodinámica
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