Abstract
The effect of sinusoidal serrations applied to the leading-edge of the vanes of a realistic fan stage is investigated using high-fidelity numerical simulations. The CFD solver PowerFLOW based on a hybrid lattice-Boltzmann/very-large-eddy-simulation model is used to compute the unsteady flow and radiated noise of the 22-in source diagnostic test fan rig of the NASA Glenn Research Center. A computational model validated for three different geometries of the outlet guide vanes with straight leading edge is used. A subset of validation results is reported to prove the capability of the solver to accurately predict the influence of the stator geometry on the far-field noise. Different sinusoidal leading edge serrations are investigated for a radial and a swept stator and the same rotor and operating conditions. The influence of the serrations on the acoustic far-field and noise power level is reported in relation to the statistical properties of the velocity fluctuations in the wake of the rotor. Some noise reductions are obtained when the undulation amplitude and wavelength are large enough compared to the integral scales of the impinging turbulence fluctuations.
Original language | English |
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Pages (from-to) | 138-154 |
Number of pages | 17 |
Journal | Journal of Sound and Vibration |
Volume | 442 |
DOIs | |
Publication status | Published - 3 Mar 2019 |
Bibliographical note
Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-careOtherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.
Keywords
- Fan noise
- Source diagnostic test
- Wavy leading edge