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Practical Aspects of Making NAH Measurements
Technical Paper
1999-01-1847
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
Practical issues to consider when making measurements for Nearfield Acoustical Holography (NAH) analysis are addressed. These include microphone spacing and placement from the test surface, number of microphones and array size, reference microphone number and placement, and filtering of the data.
NAH has become an accepted analysis tool so that several commercial packages are available. Its application is limited to test surfaces that are fairly planar, lending itself well to tire testing, front of dash testing, engine face testing, etc. In order to achieve accurate NAH results, the measurement and analysis process must be clearly understood on a practical level.
Understanding the advantages and limitations of NAH and the measurement parameters required of it will allow the user to determine if NAH is applicable to a particular test object and environment.
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Citation
Dumbacher, S., Brown, D., Blough, J., and Bono, R., "Practical Aspects of Making NAH Measurements," SAE Technical Paper 1999-01-1847, 1999, https://doi.org/10.4271/1999-01-1847.Also In
References
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