Computational Aeroacoustics of the Coaxial Flow Exhaust System of a Gas Turbine Engine
2007 (English)In: Volume 6: Turbo Expo 2007, Parts A and B, ASME , 2007, 1531-1539 p.Conference paper (Refereed)
Jet engine noise is an environmental problem that needs to be addressed. Several methods to reduce the jet noise have been proposed in the last decades. The main issue is to find methods that reduce noise without causing considerable loss of thrust. Experimental and computational tools are mandatory in successfully reducingjet engine noise emissions. One of the challenging issues ofcomputing the jet engine noise is the presence of verylarge scales (associated with the wave length of the acousticwave) and at the same time also small scales that are responsible for the acoustical sources. In the field of Computational Aero-Acoustics (CAA) different hybrid approaches have been introduced to handle the different scales using problem specific models and methods.Here, a decomposition of flow variables is used that allowsseparation of flow and acoustic computations. Large Eddy Simulation approachis employed to compute the flow field and the acousticsources. An inhomogeneous wave equation is used to perform acousticcomputations. The paper investigates numerically the flow and the near-fieldacoustic data from a coaxial jet case with chevrons onthe core nozzle that are compared with those obtained froma baseline coaxial jet, showing the spatial character of the acoustic benefit when chevrons are used on the core nozzle.Comparisons in terms of sound pressure levels with experimental data performed with the same geometry show a good agreement.
Place, publisher, year, edition, pages
ASME , 2007. 1531-1539 p.
Aerospace Engineering Fluid Mechanics and Acoustics
IdentifiersURN: urn:nbn:se:kth:diva-48732DOI: 10.1115/GT2007-28193ISBN: 0-7918-4795-0OAI: oai:DiVA.org:kth-48732DiVA: diva2:458419
ASME Turbo Expo 2007: Power for Land, Sea, and Air (GT2007) May 14–17, 2007 , Montreal, Canada