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Since the vehicle development time becomes shorter and shorter every year in automobile industry, it is becoming more important for automotive engineers to be able to analyze each part going into a vehicle in early stage of development. Noise and Vibration (NV) engineers are often required to evaluate the performance of sound proof materials and quickly choose which one should be used in a vehicle being developed in the early stage. In a typical automobile development, Original Equipment Manufacturers (OEMs) and trim suppliers often communicate via flat sample performance, Insertion Loss and Absorption Coefficient, to decide which parts should be used for a vehicle. Flat sample data is valuable, since it shows the inherit characteristics of the layered product but should not be used as the only metric to decide which product goes into the automobile. The final metric for NV performance should be the Sound Pressure Level (SPL) suppression performance.

This paper describes an effective method with statistical energy analysis (SEA) for specifying the vehicle sound proof package that achieves the best balance between light weight and high sound insulation performance. For proposing the sound proof package in the early stages of vehicle development, it is necessary to assess a number of specifications and to pick the best design specifications for weight and sound proof performance. However, there are difficulties in achieving conflicting objectives simultaneously, and acoustic engineers need special technical know-how. In this study, a new automated optimization method is proposed that approaches the problem above. As a result, detailed sound insulation package specifications, including the thickness distribution of each part, can be obtained and these can be easily transferred to drawings. Moreover, the accuracy of this method is proven by a reduction in vehicle interior cabin sound pressure level

The Noise and Vibration (NV) development for interior quietness as related to air-borne noise of a new automobile typically undergoes several stages where each stage can consist of various prototypes. Along with these development stages, all the performance at various level such as Completely Built-Up (CBU) level to parts level need to be appropriately evaluated in order to satisfy the both demands of NV performance and weight reduction. Additionally, since the development time is limited, the performance progression through the development needs to be tracked and can be easily compared for an efficient development. Performance Design Tool (PDT) is a comprehensive vehicle development management system that allows NV engineers to establish a systematic process to make sound design decisions by creating a platform where the vehicle model performance is easily managed and analyzed.

Porous materials are extensively used in the construction of automotive sound package parts, due to their intrinsic capability of dissipating energy through different mechanisms. The issue related to the optimization of sound package parts (in terms of weight, cost, performances) has led to the need of models suitable for the analysis of porous materials' dynamical behavior and for this, along the years, several analytical and numerical models were proposed, all based on the system of equations initially developed by Biot. In particular, since about 10 years, FE implementations of Biot's system of equations have been available in commercial software programs but their application to sound package parts has been limited to a few isolated cases. This is due, partially at least, to the difficulty of smoothly integrating this type of analyses into the virtual NVH vehicle development.