Wuxi Jixing Acoustic Auto Parts Co.

Wuxi, United States

Wuxi Jixing Acoustic Auto Parts Co.

Wuxi, United States
SEARCH FILTERS
Time filter
Source Type

Fung K.K.H.,Wuxi Jixing Acoustic Auto Parts Co. | Li X.,Wuxi Jixing Acoustic Auto Parts Co. | Huang W.,Wuxi Jixing Acoustic Auto Parts Co. | Wentzel R.E.,Wuxi Jixing Acoustic Auto Parts Co. | zhu K.,Wuxi Jixing Acoustic Auto Parts Co.
SAE International Journal of Passenger Cars - Mechanical Systems | Year: 2011

Several methods have been established to measure the normal incidence transmission loss of noise control materials using the standing wave tube. In the automotive NVH field, multi-layered systems are common-place, for example in the interaction between the traditional mass-decoupler dash insulator and the front dash sheet metal. Most of the sound transmission loss studies utilizing the standing wave tube have so far been focused on single layer systems with only a limited number of studies on multi-layered systems. Therefore there is only some degree of information on the correlation between this said method and the more widely accepted two-room methods of determining sound transmission properties in these systems. The paper details an empirical study using a four-microphone standing wave tube using the transfer matrix method and a couple of methods utilizing the traditional hemi-anechoic and reverberant room set up, including one using sound pressure technique and the other using sound intensity technique. The range of materials in the study includes porous and barrier materials in single and multi-layered system configurations. It is found that the material sound transmission loss ranking is generally consistent between the two-room methods using SAE J1400 and ISO 15186 and the standing wave tube method. However when the samples are coupled with a steel plate, there are resonance conditions which makes ranking the performance difficult. Also no consistent difference between the results of the two-room methods and the standing wave method is found, which makes correlating the data between the different methods difficult. © 2011 SAE International.


Tian X.,Wuxi Jixing Acoustic Auto Parts Co. | Yu W.,Wuxi Jixing Acoustic Auto Parts Co. | Wentzel R.E.,Wuxi Jixing Acoustic Auto Parts Co. | Zhu K.,Wuxi Jixing Acoustic Auto Parts Co. | Huang W.,Wuxi Jixing Acoustic Auto Parts Co.
SAE Technical Papers | Year: 2013

PE (polyethylene) membranes are widely adopted in sound insulation pads inside vehicle. However, there are few studies on the acoustical effects of these inserted membranes. This study focuses on these effects. Frequently sound insulation is made up of two layers of felt (a pad made of cotton or synthetic fiber), separated by a PE membrane. The normal incidence sound absorption coefficient and sound transmission loss for this type of insulation construction were calculated through the micro perforated membrane theory and the analytical model (NOVA) which is based on Biot theory. Impedance tube measurement was used to derive the poroelastic properties needed to utilize these models. Comparison between the calculated and measured results showed that the absorption coefficient obtained from the micro perforated membrane theory was closer to the measured value above 3 kHz. And that calculated using NOVA was closer to the measured value below 3 kHz. The transmission loss calculated through NOVA was much closer to the measured value. But the shape of the transmission loss curves calculated through micro perforated membrane theory more closely matched that of the measured curves. The results calculated both through the micro perforated membrane theory and Biot theory didn't match the measured result well. Test errors and theory assumptions are likely causes. Modeling improvements, and enhanced test techniques will improve agreement between test and predicted data. Copyright © 2013 SAE International.

Loading Wuxi Jixing Acoustic Auto Parts Co. collaborators
Loading Wuxi Jixing Acoustic Auto Parts Co. collaborators