Computational aeroacoustics of a s eparate flow exhaust system with eccentric inner nozzle

Research output: Chapter in Book/Report/Conference proceedingPaper in conference proceeding


A major issue related to our modern way of life is the noise caused by jet engine powered airliners. Methods to reduce the jet noise were proposed in the last decades starting with the introduction of high bypass turbofan engines. A numerical investigation of flow and acoustics of a separate flow exhaust system is performed in the present paper. The goal is to investigate how the noise generated by a separate flow jet engine exhaust is influenced if the symmetry of the jet exhaust geometry is broken by having the inner nozzle and the center body off the center line axis of the fan nozzle. A decomposition of flow variables is used that allows separation of flow and acoustic computations. Large Eddy Simulation approach is employed to compute the flow field and the acoustic sources. The inhomogeneous wave equation is used to compute the acoustic near- and far-fields. Using this method, previous numerical studies of the symmetric (baseline) configuration showed good agreement between the computed data and the experimental results. Comparisons between the near- and far-field baseline concentric case and the computations obtained using the eccentric configuration are performed showing an acoustic benefit for the offset case.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Fluid Mechanics and Acoustics
Original languageEnglish
Title of host publication45th AIAA Aerospace Science Meeting Proceedings
PublisherAmerican Institute of Aeronautics and Astronautics
Publication statusPublished - 2007
Publication categoryResearch
Event45th AIAA Aerospace Sciences Meeting and Exhibit - Reno, Nevada, United States
Duration: 2007 Jan 82007 Jan 11


Conference45th AIAA Aerospace Sciences Meeting and Exhibit
CountryUnited States
CityReno, Nevada