Contribution analysis of vehicle exterior noise with operational transfer path analysis

Operational transfer path analysis is applied in this study to identify the vibration source and its critical transfer path. A simple analytical five-degrees-of-freedom mechanical isolation system is first taken as an example to illustrate the analysis flow and to validate the accuracy of operational transfer path analysis. The acceleration amplitude spectrum of the receiver is used to prove the accuracy, and the path contribution of each path is used to identify the critical path. Operational transfer path analysis is then applied to the cab mount system of a heavy commercial vehicle to identify the vibration source and its critical transfer path. The vibration energy propagation capabilities from the four cab mounts to the driver’s seat are analyzed by operational transfer path analysis with the path contribution analysis, and the maximum vibration source is identified by the path operation contribution analysis. The analysis and evaluation method of the operational transfer path analysis introduced in this study can provide a research foundation and reference for vibration or noise source identification in mechanical systems.

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Contribution analysis of interior noise and floor vibration in high-speed trains by operational transfer path analysis

Advances in Mechanical Engineering ◽

10.1177/1687814017714986 ◽

2017 ◽

Vol 9 (8) ◽

pp. 168781401771498 ◽

Cited By ~ 8

Author(s):

Hee-Min Noh

Keyword(s):

Path Analysis ◽

High Speed ◽

Interior Noise ◽

Transfer Path ◽

Contribution Analysis ◽

High Speed Trains ◽

Floor Vibration ◽

Transfer Path Analysis

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Identification of partially coherent sound sources for centrifugal fan

Noise Control Engineering Journal ◽

10.3397/1/37696 ◽

2021 ◽

Vol 69 (1) ◽

pp. 66-76

Author(s):

Chenguang Wang ◽

Weikang Jiang

Keyword(s):

Path Analysis ◽

Mechanical Equipment ◽

Test Model ◽

Sound Sources ◽

Transfer Path ◽

Partially Coherent ◽

Contribution Analysis ◽

Coherent Sources ◽

Transfer Path Analysis ◽

Partially Coherent Sources

The signal model with multiple inputs and single output (MISO) is often used for investigating sound sources of vehicles and mechanical equipment, in which transfer path analysis (TPA) and operational transfer path analysis (OTPA) procedure are well known in industry. Sources are completely coherent, as well as completely incoherent in TPA and OTPA models. However, some mechanical devices like centrifugal fans contain not only structure-borne and air-borne sound but also vibrational source and acoustical source. The sources may be partially coherent and cannot be calculated using traditional method. In order to understand the origination of sound from the partially coherent sources of the fan, a MISO model with partially coherent inputs was developed, in which the partially coherent sources were identified by partial singular value decomposition (PSVD) method. Vibration, pressure pulsation and sound signals were measured, and partially coherent sources contribution analysis were used to calculate the contribution of sources quantitatively. A test model was built, and an experiment was conducted to verify that this method is feasible. This method is also suitable for the identification and contribution analysis of sources with partially coherent characteristics, such as automobile exhaust system. This method can calculate the contribution of partially coherent sources, which is not available in other noise source identification methods.

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