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Under city driving conditions, the powertrain represents one of the major vehicle exterior noise sources. Especially at idle and during full load acceleration, the oil pan contributes significantly to the overall powertrain sound emission. The engine oilpan can be a significant contributor to the powertrain radiated sound levels. Passive optimization measures, such as structural optimization and acoustic shielding, can be limited by e.g. light-weight design, package and thermal constraints. Therefore, the potential of the Active Structure Acoustic Control (ASAC) method for noise reduction was investigated within the EU-sponsored project InMAR. The method has proven to have significant noise reduction potential with respect to oil pan vibration induced noise. The paper reports on activities within the InMAR project with regard to a passenger car oil pan application of an ASAC system based on piezo-ceramic foil technology.

Meeting the stringent efficiency demands of next generation direct injection engines requires not only optimization of the injection system and combustion chamber, but also an optimal in-cylinder swirling charge flow. This charge motion is largely determined by the shape of the intake port arm geometry and the valve position. In this paper, we outline an extensible methodology implemented in OPENFOAM® for multi-objective geometry optimization based on the continuous adjoint. The adjoint method has a large advantage over traditional optimization approaches in that its cost is not dependent upon the number of parameters being optimized. This characteristic can be used to treat every cell in the computational domain as a tunable parameter - effectively switching cells "on" or "off" depending on whether this action will help improve the objectives.

A uniform flow distribution at converter inlet is one of the fundamental requirements to meet high catalytic efficiency. Commonly used tools for optimization of the inlet flow distribution are flow measurements as well as CFD analysis. This paper puts emphasis on the experimental procedures and results. The interaction of flow measurements and CFD is outlined. The exhaust gas flow is transient, compressible and hot, making in-situ flow measurements very complex. On the other hand, to utilize the advantages of flow testing at steady-state and cold conditions the significance of these results has to be verified first. CFD analysis under different boundary conditions prove that - in a first approach - the flow situation can be regarded as a sequence of successive, steady-state situations. Using the Reynolds analogy a formula for the steady-state, cold test mass flow is derived, taking into account the cylinder displacement and the rated speed.

Precise three-dimensional dummy head trajectories during crash tests are very important for vehicle safety development. To determine precise trajectories with a standard deviation of approximately 5 millimeters, three-dimensional video analysis is an approved method. Therefore the tracked body is to be seen on at least two cameras during the whole crash term, which is often not given (e.g. head dips into the airbag). This non-continuity problem of video analysis is surmounted by numerical integration of differential un-interrupted electrical rotation and acceleration sensor signals mounted into the tracked body. Problems of this approach are unknown sensor calibration errors and unknown initial conditions, which result in trajectory deviations above 10 centimeters.

The aerodynamic optimization of an AUDI Q5 vehicle is presented using the continuous adjoint approach within the OpenFOAM framework. All calculations are performed on an unstructured automatically generated mesh. The primal flow, which serves as input for the adjoint method, is calculated using the standard CFD process at AUDI. It is based on DES calculations using a Spalart-Allmaras turbulence model. The transient results of the primal solution are time averaged and fed to a stationary adjoint solver using a frozen turbulence assumption. From the adjoint model, drag sensitivity maps are computed and measures for drag reduction are derived. The predicted measures are compared to CFD simulations and to wind tunnel experiments at 1:4 model scale. In this context, general challenges, such as convergence and accuracy of the adjoint method are discussed and best practice guidelines are demonstrated.