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Efficient computation of spinning modal radiation through an engine bypass duct

By Xun Huang, Xiaoxian Chen, Zhaokai Ma and Xin Zhang

Abstract

The aim of this work is to accurately and efficiently predict sound radiation out of a duct with flow. The sound propagation inside a generic engine bypass duct, refractions by the shear layer of the exhaust flow, and propagation in the near field are the main focus of the study. The prediction uses either a modified form of linearized Euler equations or an alternative model based on acoustic perturbation equations, which were extended to cylindrical coordinates. The two models were compared on a canonical case of sound propagation out of a semi-infinite duct with flow. Good agreements between the predictions were achieved. The more general case of a generic aircraft engine bypass duct with flow was then investigated with the technique of adaptive mesh refinement to increase the computational efficiency. The results show that both linearized Euler equations and acoustic perturbation equations models can predict the near-field sound propagation and far-field directivity. The acoustic perturbation equations model, however, is more adaptive for its suitability to an arbitrary background mean flow

Topics: Q1, QC
Year: 2008
OAI identifier: oai:eprints.soton.ac.uk:51298
Provided by: e-Prints Soton

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Citations

  1. (2003). Acoustic Perturbation Equations Based on Flow Decomposition via Source Filtering,” doi
  2. (2005). Acoustic Radiation froma Semi-infinite Duct with a Subsonic Jet,” doi
  3. (2001). Acoustic Radiation Modelling of Aeroengine Intake Comparison BetweenAnalyticalandNumericalMethods,”AIAAPaper2001-2140, doi
  4. (1984). Adaptive Mesh Refinement for Hyperbolic Partial Differential Equations,” doi
  5. (1998). Aft Fan Duct Acoustic Radiation,” doi
  6. (1985). Automatic Adaptive Grid Refinement for the Euler Equations,” doi
  7. (2004). Calculation of Sound Propagation in Nonuniform Flows: doi
  8. (1993). Dispersion-Relation-Preserving Finite Difference Schemes for Computational Acoustics,” doi
  9. (2004). Ewert,R.,andSchröder,W.,“OntheSimulationofTrailingEdgeNoise with a Hybrid LES/APE
  10. (1977). Interaction of Sound with a Subsonic Jet Issuing from a Semi-infinite Cylindrical Pipe,” doi
  11. (2002). Modelling Tone Propagation from TurbofanInlets: The Effect ofExtendedLip Liners,” doi
  12. (1975). Note on the Radiative Directivity Patterns of Duct Acoustic doi
  13. (1998). Numerical Algorithms for Acoustic Integrals with Examples for Rotor Noise Prediction,” doi
  14. (2003). Optimized Prefactored Compact Schemes,” doi
  15. (2005). Parallel SolutionAdaptive Scheme for Predicting Multi-Phase Core Flows in Solid Propellant Rocket Motors,” doi
  16. (2000). PARAMESH: A Parallel Adaptive doi
  17. (1982). Prediction of Helicopter Rotor Discrete Frequency Noise, American Helicopter Society, Annual Forum, 38th, American Helicopter Society, doi
  18. (2000). Prefactored Small-Stencil Compact Schemes,” doi
  19. (1996). Pseudospectra for the Wave EquationwithanAbsorbingBoundary,”JournalofComputationaland doi
  20. (2004). Richards,S.K.,Zhang,X.,Chen,X.X.,andNelson,P.A.,“Evaluation of Non-Reflecting Boundary Conditions for Duct Acoustic Computation,” doi
  21. (2006). Theoretical Model for Sound Radiation from Annular Jet Pipes: Far- and Near-Field Solutions,” doi
  22. Turbofan Aft Noise Predictions Based onLilley’sWave Model,” doi
  23. (1990). Wave Equation for Sound in Fluids with Unsteady 1422 doi
  24. (2007). X.,and Zhang,X., “Computation of Fan Noise Radiation Through an Engine Exhaust Geometry with Flow,” doi
  25. (2004). Zhang,X.,Chen,X.X.,Morfey,C.L.,andNelson,P.A.,“Computation ofSpinningModal Radiation from anUnflangedDuct,”

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