Turbomachinery Aeroacoustic Calculations using Nonlinear Methods
Doctoral thesis, 2011
Noise regulations for aircraft that fly over populated areas are becoming continuously stricter. This in combination with increasing computational capabilities has boosted interest in aeroacoustic computations in the aerospace industry. New numerical methods that are able to predict noise will play a major role in future aircraft and engine designs, and validation and possibly improvements of these new methods are needed for results with satisfying accuracy.
This thesis shows how nonlinear blade row interaction computations that focus on aeroacoustics can be made in an accurate and efficient way. It is shown how the computations of a succession of blade rows with non-matching blade count can be made more efficient by utilizing the chorochronic periodicity.
The tonal acoustic response from a stator vane with rotor wake impingement is calculated with the chorochronic method and compared to a linear method, and the results are in good agreement. The harmonic balance technique was also tested for tone noise predictions and shows a good potential to be a more efficient tool than using standard time stepping for obtaining periodic solutions. The Newton-GMRES method is shown to be a suitable algorithm for obtaining convergence and for better performance of the harmonic balance computations.
Broadband noise predictions from rotor wake impingement on stators are calculated with a hybrid RANS/LES method and chorochronic buffer zones. The noise is evaluated with a FWH surface integral method.
Nonlinear
CFD
Time Spectral
CAA
Ffowcs-Williams & Hawkings
Broadband
Time lag
Computational Aeroacoustics
Fan-Noise
Rotor-Stator interaction
Buffer layer
Oscillating sphere
Newton-GMRES
Computational Fluid Dynamics
Acoustic analogies
Sponge
Counter-Rotating Propfan
Harmonic Balance Technique
Tone
FWH
Chorochronic periodicity
Hybrid RANS/LES
HA2, Hörsalsvägen 4, Chalmers Johanneberg
Opponent: John Coupland, Rolls-Royce plc, UK
Author
Martin Olausson
Chalmers, Applied Mechanics, Fluid Dynamics
An Absorbing Inlet Buffer Layer for Rotor Wake/Stator Time Domain Computations
Proceedings of ASME Turbo Expo 2009, June 8-12, 2009, Orlando, Florida, USA,;(2009)p. 709-718
Paper in proceeding
Aeroacoustics and Performance Modeling of a Counter-Rotating Propfan
Proceedings of ASME Turbo Expo 2010, June 14-18, 2010, Glasgow, UK,;(2010)
Paper in proceeding
Evaluation of Nonlinear Rotor Wake/Stator Interaction by using Time Domain Chorochronic Solver
Proceedings of the 8th International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows (ISAIF), Lyon, July 2007,;(2007)
Other conference contribution
Nonlinear Rotor Wake/Stator Interaction Computations
Proceedings of the 18th International Symposium on Air Breathing Engines (ISABE), Beijing, China, 2007,;(2007)
Other conference contribution
Absorbing Inlet Boundary Analysis of Rotor Wake/Stator Time Domain Computations
16th AIAA/CEAS Aeroacoustics Conference, 7-9 June 2010, Stockholm, Sweden,;(2010)
Other conference contribution
Rotor Wake/Stator Broadband Noise Calculations Using Hybrid RANS/LES and Chorochronic Buffer Zones
15th AIAA/CEAS Aeroacoustics Conference, 11-13 May, Miami, Florida,;(2009)
Other conference contribution
Areas of Advance
Transport
Energy
Subject Categories
Fluid Mechanics and Acoustics
ISBN
978-91-7385-481-8
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 3162
HA2, Hörsalsvägen 4, Chalmers Johanneberg
Opponent: John Coupland, Rolls-Royce plc, UK