Abstract
This study numerically investigates the effects of fluid-structure interaction (FSI) on the trailing-edge noise, particularly for the cases of wake instability and Karman vortex shedding. The trailing edge is modeled as a flat plate with an elastic cantilever end and its flow-induced vibration is solved by an eigenmode analysis with the Galerkin method. The flow and sound coupled in the FSI analysis are computed on the moving grid by a direct numerical simulation (DNS) procedure. The computed result of wake instability shows that when the first-eigenmode natural frequency ω n of the cantilever is close to be resonant with the wake characteristic frequency ω c , the sound pressure level (SPL) is significantly reduced by 20 dB at ω n /ω c =0.95, or increased by 15 dB at ω n /ω c =1.05, for all angles. For the Karman vortex shedding, a similar frequency modulation occurs via FSI, if ω n is close to ω c . The flow and acoustic details are somewhat different for this case but a considerable noise reduction was also possible for angles from -120° to +120°.
Original language | English |
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Pages (from-to) | 1426-1435 |
Number of pages | 10 |
Journal | Journal of Mechanical Science and Technology |
Volume | 22 |
Issue number | 7 |
DOIs | |
Publication status | Published - 2008 Jul |
Keywords
- Fluid-structure interaction
- Frequency modulation
- Karman vortex shedding
- Trailing-edge noise reduction
- Wake instability
ASJC Scopus subject areas
- Mechanics of Materials
- Mechanical Engineering