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The design of the PORSCHE wind tunnels - two facilities, one in full- and the other in quarter-scale - was determined by the demand for simulating both passenger car models and racing vehicles. One peculiarity, the very low ride height of the latter requires a reduction of the oncoming boundary layer that develops along the test- section floor. The number of difficult practical engineering problems in using and operating full-scale moving belts (*Bearman et al. [14]), led to the development of two suction systems using porous plates in the test section floor. These have been installed in the full-scale and in the 1:4 - scale windtunnels. For verification or optimization of the originally estimated suction rates required to meet realistic road conditions, a number of experiments on the road and in a moving-belt facility were conducted and the results compared to values from the suction facilities.

Numerical methods for brake squeal analysis are widely accepted in industry. The use of complex eigenvalue analysis is a successful approach to predict the appearance of squeal noise. Using simulation in an early design stage reduces time to market, saves costs, and improves the physical behavior and robustness of the brake system. State of the art of brake simulation comprises sampling for many parameter sets in a wide range of interesting values. Based on high performance, stability maps can be created in short time containing many results, which gives a deep insight into the brake behavior under varying parameters. An additional benefit of sampling is the possibility to detect parts with high potential for improving the NHV comfort. In the sequel, mathematical optimization methods like topology optimization or shape optimization are used for systematic improvements.

Optimization-based strategy planning for predictive optimal cruise control has the potential for significant improvements in passenger comfort and fuel efficiency. It is, however, associated with a high computational complexity that complicates its implementation in an electronic control unit. When implementing predictive cruise control, real-time capability must be ensured while maintaining optimal control performance in the presence of disturbance and model uncertainty. Real-time capability can be achieved either by a significant simplification of the optimization problem or by a layered control approach, combining the strategy planner with a low-level controller. Both approaches, however, are prone to deteriorate optimal control performance, particularly in the presence of disturbance. We present a model-predictive controller structure that extends the layered control approach by using the same optimization algorithm on two layers.

The Porsche 1:4-scale model wind tunnel was upgraded with a moving belt in combination with basic and distributed boundary layer suction devices. The belt is placed between the rotating wheels of the model with the external underfloor balance in operation. Special attention was given to providing a sufficient length of the belt with regard to road simulation for the aerodynamic optimization of race car models with their specific wake behavior. The boundary layer suction systems control the regions beyond the belt. Furthermore the balance was equipped with a pitch angle adjustment system in order to simulate the spring deflections of a moving vehicle. Results from a series of measurements taken from one race car model and one passenger car model are presented in order to investigate the influence of the boundary layer-, wheel rotation- and pitch adjustment-controls on the characteristic aerodynamic figures of the models.

The scope of this work is to propose a methodology to define multicomponent surrogate mixtures which describe the main evaporation characteristics of real gasoline fuels. Since real fuels are commonly complex mixtures with hundreds or thousands of hydrocarbons, their exact composition is generally not known. Only global characteristics are standardized. An accurate modeling of such complex mixtures in 3D-CFD requires the definition of a suitable surrogate. So far, surrogate mixtures have mostly been defined based on their combustion properties, such as ignition delay or burning velocity, irrespective of their evaporation characteristics. For this reason, in this work, a systematic study is carried out to develop a methodology to define mixtures of representative components that mimic the evaporation behavior of real fuels.

A new optical system to analyse 3D deformations crashed vehicles is in use at Porsche’s Crash Test Facility. This technology is based on the mathematical law that the spatial location of a point is clearly definable if it is represented by at least 2 images. With the help of an high resolution digital camera, highly developed image processing and photogrammetric algorithms, an automated deformation analysis system is realized. This new measurement technology has numerous advantages over conventional devices, such as coordinate measurement machines, multi section arms and analog photogrammetry. In one example of crash tests the application of this system is described. Comparisons with conventional measurement devices regarding accuracy, costs and process optimization are presented. An outlook to further innovations in analysis of safety tests, if photogrammetry is used as a basic technology, is given.