The effects of windscreen flow on noise in motorcycle helmets

John Kennedy, Michael Carley, Nigel Holt, Ian Walker

Research output: Contribution to conferencePaper

  • 2 Citations

Abstract

Vortex shedding from a motorcycle windscreen results in three flow regions in which the rider's helmet may be immersed. First, the helmet may be completely in the free stream. Second, it may be in the path of vortex shedding from the windscreen. Third it may be underneath the shed vortices and shielded from the free stream by the windscreen. On-track noise tests were conducted and showed a difference in sound pressure level of more than 10dB and a change in spectra content, due to changes in riding position and helmet angle. Similar tests carried out in a wind tunnel, using simultaneous microphone and flow visualization measurements, allowed the identification of the flow regions. The potential contribution of vortex shedding to the noise was assessed using wavelet analysis to identify intermittent flow structures.

Conference

Conference161st Acoustical Society of America Meeting
CountryUSA United States
CitySeattle, WA
Period23/05/1127/05/11

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vortex shedding
wavelet analysis
flow structure
wind tunnel
visualization
vortex
effect
motorcycle
test

Cite this

Kennedy, J., Carley, M., Holt, N., & Walker, I. (2011). The effects of windscreen flow on noise in motorcycle helmets. 040005. Paper presented at 161st Acoustical Society of America Meeting, Seattle, WA, USA United States.DOI: 10.1121/1.3646304

The effects of windscreen flow on noise in motorcycle helmets. / Kennedy, John; Carley, Michael; Holt, Nigel; Walker, Ian.

2011. 040005 Paper presented at 161st Acoustical Society of America Meeting, Seattle, WA, USA United States.

Research output: Contribution to conferencePaper

Kennedy, J, Carley, M, Holt, N & Walker, I 2011, 'The effects of windscreen flow on noise in motorcycle helmets' Paper presented at 161st Acoustical Society of America Meeting, Seattle, WA, USA United States, 23/05/11 - 27/05/11, pp. 040005. DOI: 10.1121/1.3646304
Kennedy J, Carley M, Holt N, Walker I. The effects of windscreen flow on noise in motorcycle helmets. 2011. Paper presented at 161st Acoustical Society of America Meeting, Seattle, WA, USA United States. Available from, DOI: 10.1121/1.3646304
Kennedy, John ; Carley, Michael ; Holt, Nigel ; Walker, Ian. / The effects of windscreen flow on noise in motorcycle helmets. Paper presented at 161st Acoustical Society of America Meeting, Seattle, WA, USA United States.1 p.
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