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The increased focus and demands on the reduction of fuel consumption and CO2 requires the automotive industry to develop and introduce new and more energy efficient powertrain concepts. The extensive utilisation of downsizing concepts, such as boosting, leads to significant challenges in noise, vibration and harshness (NVH) integration. This is in conflict with the market expectation on the vehicle's acoustic refinement, which plays an increasingly important role in terms of product perception, especially in the premium or luxury segment. The introduction of the twin charger boosting system, i.e. combining super and turbo charging devices, enables downsizing/speeding in order to achieve improved fuel economy as well as short time-to-torque, while maintaining high driving dynamics. This concept requires also extensive consideration to NVH integration. The NVH challenges when integrating a roots type supercharger are very extensive.

Absorptive and isolating encapsulations or enclosures are commonly encountered around different noise-emitting components within the car industry. Not least for electric drive units, whose air borne noise shares often are dominant in the 2-6 kHz region, encapsulations can provide a cost and weight efficient noise abatement solution. The main constrains related to the acoustic performance when designing an encapsulation for electric drive units are surface coverage due to geometrical complexities, allowable package space (setting limits for maximum thickness of the encapsulation), weight and finally cost. The numerical simulation techniques for quantifying the acoustic performance in terms of insertion loss are challenging, since the encapsulations are partly compressed and far from homogeneous for example.

In the automotive industry, there is an increasing need for gaining efficiency and confidence in the prediction capability for various attributes. Often, one component or sub-system is used in a number of car models of one vehicle platform. Many of these components are potential sources of noise, vibration and squeak and rattle. In order to provide an early prognosis, vibro-acoustic source characterization in combination with the source-to-response transfer behavior are required. This paper describes the process of predicting the vibrational behavior due to a woofer, which could induce squeak and rattle, on a door panel. Blocked forces, determined indirectly in-situ by frequency response functions and operational accelerations, were used for quantifying the source activity. Those forces were in a second step loaded on to a finite element model in order to predict the response when the speaker was mounted to another position in an upcoming car model.