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Article

Aeroacoustics of an elastic element in unsteady flow of low Reynolds numbers

Authors: Schickhofer, L., Dahlkild, A. A., Mihaescu, M
Document Type: Article
Pubstate: Published
Journal: 22nd AIAA/CEAS Aeroacoustics Conference
Volume:   
Year: 2016

Abstract

Vibrations of elastic structures are a common occurrence in numerous fields of engineering such as aeronautics, aerodynamics, civil engineering, and biomechanics. Particular effort is dedicated to aeroacoustics of elements that are excited to oscillatory behaviour due to fluid instabilities. The current study is concerned with the numerical investigation of the flow-induced vibrations of a flexible, beam-like element in crossflow at low Reynolds numbers of Re=100-1000 by means of fluid-structure interaction simulations. The aeroacoustics in the near field are assessed with direct computation of the compressible airflow. Additionally, an acoustic analogy is applied, characterising the acoustic sources and the corresponding sound propagation. At low Reynolds numbers and high elastic moduli the dipole source produces the highest pressure perturbation in the near field. At higher Reynolds numbers and low elastic moduli, however, the monopole source due to structural vibrations becomes the important sound generating mechanism.