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Accession Number N20120010347
Title Influence of Realistic Reynolds Numbers on Slat Noise Simulations.
Publication Date Jun 2012
Media Count 16p
Personal Author D. P. Lockard M. M. Choudhari
Abstract The slat noise from the 30P/30N high-lift system has been computed using a computational fluid dynamics code in conjunction with a Ffowcs Williams-Hawkings solver. Varying the Reynolds number from 1.71 to 12.0 million based on the stowed chord resulted in slight changes in the radiated noise. Tonal features in the spectra were robust and evident for all Reynolds numbers and even when a spanwise flow was imposed. The general trends observed in near-field fluctuations were also similar for all the different Reynolds numbers. Experiments on simplified, subscale high-lift systems have exhibited noticeable dependencies on the Reynolds number and tripping, although primarily for tonal features rather than the broadband portion of the spectra. Either the 30P/30N model behaves differently, or the computational model is unable to capture these effects. Hence, the results underscore the need for more detailed measurements of the slat cove flow.
Keywords Broadband
Computational fluid dynamics
Ffowcs williams-hawkings equation
Near fields
Reynolds number

Source Agency National Aeronautics and Space Administration
NTIS Subject Category 51A - Aerodynamics
Corporate Author National Aeronautics and Space Administration, Hampton, VA. Langley Research Center.
Document Type Conference proceedings
Title Note N/A
NTIS Issue Number 1226
Contract Number N/A

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