Experiments in Fluids

, 57:136 | Cite as

Sound source localization on an axial fan at different operating points

  • Florian J. Zenger
  • Gert Herold
  • Stefan Becker
  • Ennes Sarradj
Research Article


A generic fan with unskewed fan blades is investigated using a microphone array method. The relative motion of the fan with respect to the stationary microphone array is compensated by interpolating the microphone data to a virtual rotating array with the same rotational speed as the fan. Hence, beamforming algorithms with deconvolution, in this case CLEAN-SC, could be applied. Sound maps and integrated spectra of sub-components are evaluated for five operating points. At selected frequency bands, the presented method yields sound maps featuring a clear circular source pattern corresponding to the nine fan blades. Depending on the adjusted operating point, sound sources are located on the leading or trailing edges of the fan blades. Integrated spectra show that in most cases leading edge noise is dominant for the low-frequency part and trailing edge noise for the high-frequency part. The shift from leading to trailing edge noise is strongly dependent on the operating point and frequency range considered.


Point Spread Function Sound Source Microphone Array Sound Source Localization Sound Power Level 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Florian J. Zenger
    • 1
  • Gert Herold
    • 2
  • Stefan Becker
    • 1
  • Ennes Sarradj
    • 2
  1. 1.Institute of Process Machinery and Systems EngineeringFriedrich-Alexander University Erlangen-NürnbergErlangenGermany
  2. 2.Chair of Technical AcousticsBrandenburg University of TechnologyCottbusGermany

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