Determination of the acoustical source characteristics of an internal combustion engine by using several calibrated loads
✍ Scribed by L. Desmons; J. Hardy; Y. Auregan
- Publisher
- Elsevier Science
- Year
- 1995
- Tongue
- English
- Weight
- 583 KB
- Volume
- 179
- Category
- Article
- ISSN
- 0022-460X
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✦ Synopsis
A least squares method is applied to characterize an internal combustion engine considered as a noise source. It is shown that, although extremely severe conditions exist (high sound pressure level, high temperatures, turbulent flow, etc.), a linear theory can predict the noise level at the output of the exhaust systems with a surprisingly good accuracy when the transfer matrix is known. The measurements avoid the use of calibrated internal microphones; only one external microphone and a set of calibrated loads are needed. An indirect validation of the linearity hypothesis is achieved and the predicted exhaust noise level is compared with experimental results in the case of a tube and in the case of a silencer composed of three expansion chambers.