Elimination of a High-Frequency Narrow-Band Noise Component in a Low-Noise Automobile Wind Tunnel

Format:

Book

Conference/Event

Author/Creator:

von Heesen, Wilhelm, author.

Conference Name:

International Congress & Exposition (1996-02-26 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 1996

Summary:

ABSTACTThe out-of-flow background noise spectrum in the test section of the full-scale low-noise automobile wind tunnel facility of BMW Technik GmbH in Munich showed a pronounced hump around 2 kHz Although this excess noise component was audible, it did not interfere with the automobile flow noise studies conducted in the tunnel An experimental study was performed to identify the source mechanism. It was found that the excess noise is generated by small cavities in the face side of the impeller blade tips When the cavities were closed the excess noise component completely dissappered The peak spectral level of the fan noise was reduced by as much as 30 dB The overall out-of-flow level reduction in the test section was 3 dB(A)

Notes:

Vendor supplied data

Publisher Number:

960904

Access Restriction:

Restricted for use by site license