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, Volume 120, Issue 7–8, pp 22–27 | Cite as

Novel Approach to the Calculation of Flow-acoustic Phenomena

  • Drasko Masovic
  • Eugène Nijman
  • Jan Rejlek
Cover Story Acoustics
  • 37 Downloads

Sound radiation from an open pipe with flow is a common problem in flow acoustics. In automotive applications it naturally appears at tailpipes of exhaust systems and air outlets of ventilation systems. In this article, the Virtual Vehicle Research Center presents a new approach to reduce the complexity of flow noise calculations.

Limits of Existing Techniques

Sound radiation from an open pipe is affected by several flow-acoustic phenomena: convection by the mean flow of fluid, diffraction at the edge of the pipe opening, and refraction in the mixing region of the flow in front of the opening. Numerical calculations taking into account these phenomena are very often associated with high computational costs, especially in cases of strong coupling between main flow and acoustic waves. An example of such coupling is the vortex-sound interaction at the sharp trailing edge of the pipe. The vortices shed from the edge are partly amplified by the incoming sound wave inside the pipe and, thus,...

Notes

Thanks

The research work of Drasko Masovic has been funded by the European Commission within the ITN Marie Curie Action Project “Batwoman” under the 7th Framework Program (EC grant agreement No. 605867). The authors acknowledge the financial support of the Comet K2 — Competence Centers for Excellent Technologies Program of the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit), the Federal Ministry for Digital, Business and Enterprise (bmdw), the Austrian Research Promotion Agency (FFG), the Province of Styria and the Styrian Business Promotion Agency (SFG).

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Copyright information

© Springer Fachmedien Wiesbaden GmbH, part of Springer Nature 2018

Authors and Affiliations

  • Drasko Masovic
    • 1
  • Eugène Nijman
    • 2
  • Jan Rejlek
    • 2
  1. 1.Institute of Fluid Dynamics and Engineering Acoustics, TU BerlinBerlinGermany
  2. 2.Virtual Vehicle Research CenterGrazAustria

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