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With the automotive industry's increasing focus on electromobility and the growing share of electric cars, new challenges are arising for the development of electric motors. The requirements for torque and power of traction motors are constantly growing, while installation space, costs and weight are increasingly becoming limiting factors. Moreover, there is an inherent conflict in the design between power density and efficiency of an electric motor. Thus, a main focus in today's development lies on space-saving and yet effective and innovative cooling systems. This paper presents an approach for a multi-physical optimization that combines the domains of electromagnetics and thermodynamics. Based on a reference machine, this simulative study examins a total of nine different stator cooling concepts varying the cooling duct positions and end-winding cooling concepts.

The paper describes a predictive tool for the determination of air and coolant temperatures and heat exchange resulting from the operation of heat exchangers, e.g., radiator or air-conditioner condenser in the underhood of automotive engines. The paper describes a detailed computational model where both the fluid streams are numerically solved and the phase change of the refrigerant is taken into account in a condenser simulation. An actual underhood simulation with interactions with a radiator is presented. A numerical simulation for a condenser is also presented. Reasonable agreement is shown with the test data.

The present study shows how the application of computational fluid dynamics can help to understand and optimize the flow field in a passenger compartment in order to achieve an optimum of thermal comfort for the occupants. The flow field and temperature distribution in a passenger compartment have been calculated using the commercial CFD program STAR-CD. In combination with a thermophysiological model for the passengers, the computational results are used to evaluate the thermal comfort of the occupants and compare different geometrical modifications. The computational mesh consisting of around 3 millions hexahedra cells resolves all geometrical details of the car cabin including the air ducts, air nozzles and louvers. Natural convection, heat conduction and radiation are taken into account. One standard climatisation mode, the winter heat-up mode has been simulated. A special emphasis of the numerical investigations is the optimization of the ventilation of the front and rear legroom.

The new SL from Mercedes-Benz was conceived as a pure-bred roadster, i.e. without a fixed roll-over bar which would mar the looks of this open sports car and moreover emphasize the added risk of injury in the event of a roll-over accident. At the same time, the aim was to further enhance occupant safety in the event of such a roll-over. These aims led to the designing of a completely new kind of passive protection system which comes into operation automatically if a roll-over is imminent. Between the rear seats and the soft-top recess, a roll-over bar was therefore integrated; this is mounted on a pivot system and does not affect the apearance of the car when lowered. A sensor system, which is also new, registers driving situations which could result in a roll-over. As a consequence of this, the roll-over bar is raised via a spring/damper mechanism and locked into position.

As the late combustion phase in SI engines is of high importance for a further reduction of fuel consumption and especially emissions, the impacts of unburnt mass, located in a small volume with a relatively large surface near the wall and in the top land volume, is of high relevance throughout the range of operation. To investigate and quantify the respective interactions, a state of the art Mercedes-Benz single cylinder research SI-engine was equipped with extensive measurement technology. To detect the axial and radial temperature distribution, several surface thermocouples were applied in two layers around the top land volume. As an additional reference, multiple surface thermocouples in the cylinder head complement the highly dynamic temperature measurements in the boundary zones of the combustion chamber.