Study on Automotive Interior Structure-Borne Sound Based on TPA

Abstract

Research and/or Engineering Questions/Objective The inertia excitation and the unbalanced force is one of main excitation sources, which induce the vehicle interior structure-borne noise. The research on the optimization of the PT mounting system is very common, but the research on how to modify the vehicle panel to reduce the structure-borne noise induced by engine is very few. The paper utilizes CAE technology and transfer path analysis for identifying the main transfer path, and the control of the vehicle interior structure-borne noise excited by engine excitation is well implemented. Methodology A new TPA method based on the CAE technology is proposed to analyze the vehicle interior structure-borne noise in present work. This method can implement the control of the vehicle interior structure-borne noise excited by engine excitation through the control of the transfer function of subsystem on the main transfer path. In present method, the finite element method is used to establish the dynamics model of vehicle PT-Body coupled system is establish, and the prediction of vehicle interior structure-borne noise is investigated, then the main transfer path is identified by using TPA method on the basis of subsystem response. Finally, the Panel contribution Analysis (PCA) techniques can be implemented on the structure- acoustic transfer function of body-subsystem in the uppermost transfer path, and the dominant panel contributions can be identified. Results This paper considers a problem of micro-car interior structure-borne noise generated by engine excitation. The micro-car is simply treated with a coupled system composed with two subsystems, namely body-subsystem and PT-subsystem. In the light of above method, the prediction on vehicle interior structure-borne noise induced by the engine second excitation is obtained. As the main transfer path then is found out. The PCA technology is utilized to analyze the special structural acoustic transfer function. The result shows the main panels are the dash panel and the roof, respectively. The topography technology is applied to optimize the main panel to improve the performance. The result shows the proposed method reduce the vehicle interior structure-borne noise effectively. Limitations of this study The vehicle interior structure-borne noise induced by the chassis subsystem is not studied and the chassis transfer path analysis is also not carried out in present work. This paper has not studied the influence due to the error of CAE model. There are some others TPA methods such as Fast TPA, multilevel TPA, presently. These ideas in other TPA methods should be used for reference in present method. What does the paper offer that is new in the field in comparison to other works of the author A new TPA method based on the CAE technology is proposed to analyze the vehicle interior structure-borne noise induced by engine excitation in present work. The CAE technology will be introduced to improve the range and effect of TPA. This paper introduces the PCA techniques into TPA method, and synergies the strengths of PCA and TPA methods. The proposed method improves the optimization efficiency compared with classical CAE technology. Compared to the classical TPA, the present method provides the NVH design directions at detailed engineering phase even at the concept phase. Conclusion The new TPA method synergies the strengths of CAE and TPA methods, is feasible to analyze the interior structure-borne noise induced by engine excitation. The PCA technology is well applied into the optimization of vehicle interior structure-borne noise. The present method is applicable and can provide broad guidance for interior noise control in the design process.

F2012-J05-015