Sound source localisation at an axial contra-rotating fan by means of PIV and rotational beamforming

Christian  Friebe; Ralph  Krause; Michael  Kerscher; Oliver  Velde

doi:10.29008/ETC2019-140

13^th European Conference on Turbomachinery Fluid dynamics & Thermodynamics

Paper ID:

ETC2019-140

Main Topic:

Fans

https://doi.org/10.29008/ETC2019-140

Authors

Christian Friebe - Institut für Luft- und Kältetechnik gGmbH
Ralph Krause - Institut für Luft- und Kältetechnik gGmbH
Michael Kerscher - gfai tech GmbH
Oliver Velde - CFturbo GmbH

Abstract

This paper describes the investigation of a contra-rotating axial fan. It has a shroud diameter of 300 mm and a rotational speed of 1920 min-1 and 1200 min-1 for the first and the second impeller, respectively. It is designed for an air-flow rate of 0.486 m3s-1 and for total pressure difference of 180 Pa (120 Pa at the first and 60 Pa at the second impeller). The main focus lies on the correlation of flow structure and the noise emission. Therefore, the flow structure is investigated by means of Particle Image Velocimetry (PIV) and the noise emission with an Acoustical Camera. PIV is established at a non-rotating model of the blades. For localizing the noise sources, a rotational beamforming algorithm is applied allowing the determination of noise sources on a rotating fan.