0
research-article

Optimization of Trailing-Edge Serrations to Reduce Open-Rotor Tonal Interaction Noise

[+] Author and Article Information
Robert Jaron

Institute of Propulsion Technology, German Aerospace Center (DLR), Müller-Breslau-Str. 8, Berlin 10623, Germany
Robert.Jaron@dlr.de

Antoine Moreau

Institute of Propulsion Technology, German Aerospace Center (DLR), Müller-Breslau-Str. 8, Berlin 10623, Germany
antoine.moreau@dlr.de

Sébastien Guérin

Institute of Propulsion Technology, German Aerospace Center (DLR), Müller-Breslau-Str. 8, Berlin 10623, Germany
sebastien.guerin@dlr.de

Rainer Schnell

Institute of Propulsion Technology, German Aerospace Center (DLR), Linder Höhe, Cologne 51147, Germany
rainer.schnell@dlr.de

1Corresponding author.

ASME doi:10.1115/1.4037981 History: Received August 08, 2016; Revised August 14, 2017

Abstract

A major source of contra-rotating open rotor tonal noise is caused by the interaction of the front-rotor wakes with the aft-rotor blades. Inspired by chevron nozzles, which increase the mixing process in jet shear layers, serrations are implemented at the front rotor trailing-edge in order to increase the wake mixing and thus reduce the tones. The depth and width of the serrations are optimized with a multi-objective, metamodel-assisted evolutionary algorithm. For each member a steady-state Reynolds-Averaged Navier-Stokes (RANS) simulation is performed which is coupled with an analytical noise prediction method to evaluate the noise reduction due to the serrations. The results confirm that tonal interaction noise can be reduced by means of trailing-edge serrations. It is found that the major noise reduction mechanism for wake interaction is attributed to increased destructive interferences occurring in spanwise direction. The tonal noise generated through the interaction of the rear rotor potential field with the front rotor trailing edge is also slightly reduced because of the circumferential and axial shift of the serrated trailing edge. Furthermore the present study demonstrates the feasibility of performing an acoustic optimization with a hybrid approach that predicts the noise analytically and extracts the aerodynamic input data from a steady-state Reynolds -Averaged Navier-Stokes flow solution.

Copyright (c) 2017 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In