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The requirements for racing car aerodynamics are far more extensive and demanding than those for passenger cars. Since many of the relevant aerodynamic features cannot be measured easily, if at all, Computational Fluid Dynamics (CFD) provides a detailed insight into the flow phenomena and helps in understanding the underlying physics. This paper summarizes some aspects of the aerodynamic optimization process for the Opel Calibra ITC racing car, starting from the production car design and including exterior and interior aerodynamic computations, together with wind tunnel experiments.

The goal of constructing squeal free brakes is still difficult to achieve for design engineers. There are many measures that are beneficial to avoid or decrease brake squeal, examples are the increase in damping and the introduction of asymmetries in the brake rotor. For an efficient design process these measures have to be quantified. This is difficult due to the high complexity of the system which is caused by the contact conditions and the complicated properties of the pad material which consists of a vast amount of different components. The attempt presented in this paper is to use fundamental models of the excitation mechanism for brake squeal in order to quantify the rate of asymmetry and damping required to get far away from the squeal boundary. The relation can be helpful to generate adequate objective functions for a systematic structural optimization of brake rotors against squeal and can be used as a design guideline.

In this publication, we want to present two examples to demonstrate how the SKO method can be used in practice. The SKO method is a tool for topological optimization and is based on the simulation of biological load carriers. The first example is an engine bracket which had to be optimized to reduce the maximum von Mises stress by a factor of at least 60%. The initial design of the bracket was a u-profile with some ribs inside. In the first step the arrangement of the ribs was optimized, which led to a stress reduction of 20 %. In the second step the cross section was optimized, leading to the desired overall stress reduction of 60%. Furthermore, the weight of the optimized design was reduced by nearly 25 % in comparison to the initial design. In the second example, the SKO method is used to create holes in the spoke region of a wheel-rim. The resulting new spoke design has a weight reduction of 26 % in this region in comparison with a production rim.

This paper describes the design process of a complete HVAC module using computational fluid dynamics (CFD). CFD gives a detailed insight on the flow characteristics of HVAC components even in early design stages. Due to a close coupling with CAD/CAE systems the number of prototypes, costs, and development time can be reduced. Optimised air duct designs lead to reduced pressure losses, and turbulence levels, that consequently decrease flow induced noise. Simultaneously the air distribution of the duct outlets is uniformed. Thermal analysis gives information about the heat transfer and hot/cold air mixing process inside the HVAC module.

One powerful tool for the optimization of engineering components is solution 200 of MSC/Nastran. The user is able to define nearly every kind of objective function and restriction with the help of synthetic responses, in addition to the usual responses. For sizing problems, solution 200 is well-established and reasonably user-friendly. This is not the case in the field of shape optimization. The main problem is the creation of basis vectors, which are needed to describe the shape variations. There are some methods included in solution 200 to create these vectors, but for complex engineering components these methods are difficult to use and very time-consuming. The program Shape200 has been developed to reduce the effort required to create basis vectors.

The worldwide automotive industry is currently preparing for a market introduction of hydrogen-fueled powertrains. These powertrains in fuel cell electric vehicles (FCEVs) offer many advantages: high efficiency, zero tailpipe emissions, reduced greenhouse gas footprint, and use of domestic and renewable energy sources. To realize these benefits, hydrogen vehicles must be competitive with conventional vehicles with regards to fueling time and vehicle range. A key to maximizing the vehicle's driving range is to ensure that the fueling process achieves a complete fill to the rated Compressed Hydrogen Storage System (CHSS) capacity. An optimal process will safely transfer the maximum amount of hydrogen to the vehicle in the shortest amount of time, while staying within the prescribed pressure, temperature, and density limits. The SAE J2601 light duty vehicle fueling standard has been developed to meet these performance objectives under all practical conditions.