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The statistical energy analysis (SEA) is widely used to support the development of the sound package of cars. This paper will present the preparation of a model designed to investigate the sound package of the new Audi A3 and associated correlation against measurements. Special care was given during the creation of the model on the representation of the structure to enable the analysis of structure borne energy flow on top of the classical airborne analysis usually done with SEA. The sound package was also detailed in the model to allow further optimization and analysis of its performance. Two real life load cases will be presented to validate the model with measurements. First, the dominating powertrain and a second load case with dominating rolling noise. An analysis of the contribution of the different source components and a way to diagnose the weak paths of the vehicle will be presented. The focus of this investigation is the application of optimally adjusted treatment.

During series production of modern combustion engines a major challenge is to ensure the correct operation of every engine part. A common method is to test engines in end-of-line (EOL) cold test stations, where the engines are not fired but tugged by an electric motor. In this work we present a physically based 0D model for dynamic simulation of combustion engines under EOL test conditions. Our goals are the analysis of manufacturing faults regarding their detectability and the enhancement of test procedures under varying environmental conditions. Physical experiments are prohibitive in production environments, and the simulative approach reduces them to a minimum. This model is the first known to the authors exploring advanced engine test methods under production conditions. The model supports a wide range of manufacturing faults (with adjustable magnitude) as well as error-free production spread in engine components.

Good lighting is crucial for safe driving at night. Unfortunately, many parameters are contributing to the final result of the individual tolerances of car body, dynamics and headlamp: the resulting aim. The paper will analyze individual tolerance contributors from car body parameters like load, tire pressure, suspension as well as temperature parameters of chassis and plastic parts. The investigation shows that the headlight aim can fluctuate in a worst case scenario more than ±0.3°.

The paper will describe actual investigations on safety improvements by new lighting functions. Especially the new chance of projections on the road surface either by simple reflector technology or by modern signature and pattern projection will be investigated. Different prototype patterns will be checked by a set of new parameters, e.g. reaction time to signals, clear understanding, minimum and optimum visual contrasts. The results show that high contrasts and dynamic effects are most effective.

Brake particle emissions as a part of non-exhaust emissions are becoming more and more relevant, various international research activities can be stated. Also from the legislation side, first hints are given in regards of possible regulations. One possible approach for the reduction of brake particle emissions deals with the collection of those particles close to the foundation brake. The presented paper will follow such an approach and give some insights. In a first step, the technical layout is described for bench and vehicle testing. While for bench testing a PMP-like style of the setup could be chosen, the vehicle test setup is oriented on conventional wheel dust measurements. Hence, presented results of laboratory testing are dealing with PN and PM measurements. Also the impact on particle size distribution is discussed. It can be stated, that the particle collecting system is able to improve PN and PM emissions. Additionally, ultra-fine particles are almost eliminated.

Lightweighting of cars will remain one important goal for car producers. One milestone for lightweight technologies was the Audi Space Frame ASF‚. New generations of ASF cars will follow. Only the experience from the A 8 shows, which innovative technologies for these new generations will bring us one step forward. It's the combination of alloy modifications, innovative forming and joining technologies that leads into the future.

For integrating Life Cycle Assessment into the design process it is more and more necessary to generate models of single life cycle steps respectively manufacturing processes. For that reason it is indispensable to develop parametric processes. With such disposed processes the aim could only be to provide a tool where parametric environmental process models are available for a designer. With such a tool and the included models a designer will have the possibility to make an estimation of the probable energy consumption and needed additive materials for the applied manufacturing technology. Likewise if he has from the technical point of view the opportunity, he can shift the applied joining technology in the design phase by changing for instance the design.

In the production of brake disc pads, powder mixes containing, metal chips, filling agents, and abrasive materials, as well as phenolic resins are processed and molded to a back plate by way of pressure and temperature. These molded disc pads reach their final strength through additional thermal treatment such that the phenolic resins approach “full cure”. This production process leads to anisotropic, viscoelastic, and to a certain extent heterogeneous materials which are - like the brake system- increasingly subject to even greater demands. E.g. apart from tribological characteristics, more and more focus is placed on structure-mechanical properties to improve the braking comfort.

This paper shall give an idea of a lighting strategy a car company could have decided in an senior management circle. It is a medium to long term approach dealing with styling, design, innovation, quality and environmental aspects. Cost influences will be pointed out. It gives examples how different target conflicts could be handled and how or where to find mutual gain. Some “natural” conflicts between styling, engineering and marketing in car development are discussed. The different roles a car company could play in the development process will be shown. Is a car company responsible for the application of parts only or should it take the development leadership? And how could it be in future? Chances and risks will be pointed out.

Issues relating to the reduction of CO₂ emissions and energy consumption are currently more important than ever before. In the construction engineering and automotive sectors research and development efforts are focused closely on efficient buildings and automobiles. The designated target is a reduction in greenhouse gas emissions and overall energy demand. However, almost all approaches focus solely on either "buildings" or "mobility." By considering both aspects as a single holistic system, further energy saving potential arises due to synergetic effects. The goal of current research projects relating to Smart Homes and Vehicle to Building (V2B) is to smooth the electrical load profile on a household level rather than to reduce the individual-related total energy consumption and thereby the CO₂ emissions.

Two research fields are presented in this paper covering new lighting functions. In the first part, a study is presented that evaluates distraction by light animations. 41 test subjects were involved, and a situation was constructed with several traffic participants and an animated-light vehicle parked so as to be conspicuously within the test subjects’ view. 91% of the test subjects stated they felt little or no distraction or impairment from the light display on the parked car. 29% noticed something conspicuous about the test vehicle. 22% indicated they had noticed the car’s lights flashing as its central locking system was operating. Only 7%—three of the 41 participants—noticed the animations in addition to their traffic monitoring. Of these, two said they didn’t feel disturbed at all by the animations while the third found it only very slightly distracting. Nobody said the distraction or impairment was “neutral”, “little bit” or “strong”.

The deposition behavior of brake wear particles on the surface of a wheel and the mechanisms on it have not been fully understood. In addition, the proportion of brake wear particles deposited on the wheel surface compared to the total emitted particles is almost unknown. This information is necessary to evaluate the number- and mass-related emission factors measured on the inertia dynamometer and to compare them with on-road and vehicle-related emission behaviour. The aim of this study is to clarify the deposition behavior of brake particles on the wheel surface. First, the real deposition behaviour is determined in on-road tests. For particle sampling, collection pads are adapted at different positions of a front and rear axle wheel. In addition to a Real Driving Emissions (RDE)-compliant test cycle, tests are performed in urban, rural and motorway sections to evaluate speed-dependent influences.

This paper covers research findings on digital projections on the road. Data is provided for the root cause analysis of non-existing distraction proven by several studies. The study describes if and in which geometrical space road projections are visible to other road traffic participants. Such participants can be e.g. oncoming, passing drivers or pedestrians standing aside the road. The paper data shows where projections are recognizable and assignable to the original intention of the projection. A grid was created to identify the areas where digital projections could be understood and where the digital projections were just illegible. A dominant factor is the grazing incidence. The photons are distributed over a larger area and only the driver’s view makes a virtual compression of the illuminated area in order to make the signals legible. The results show that distraction for other road participants is unlikely for any position outside very limited areas.

When designing new vehicles, the legal requirements of the countries in which the vehicles are homologated must be observed and implemented. The manufacturers try to consider the legal framework of the UN-ECE (United Nations Economic Commission for Europe), CCC (China Compulsory Certification) and FMVSS (Federal Motor Vehicle Safety Standard) 108 in the same vehicle to keep the variance low. For the appearance of the vehicle, the position of the light modules in the front of the vehicle is important. In addition to the surface requirements of lighting functions, the positions of the low beam (LB), high beam (HB) and the position of daytime running lights (DRL) are also regulated. When it comes to these mounting positions, the legislation between the US and the EU differs quite significantly.

1. The present work introduces an approach for the analysis of the noise propagation behavior of mechatronic brake systems in modern passenger vehicles. While on the one hand, the number of features realized through the mechatronic brake system is strongly increasing; on the other hand, a continuous reduction of the overall vehicle interior noise level can be observed. This leads to an increase of interfering noise phenomena in the vehicle interior that customers might perceive as insufficient product quality. Therefore, noise elimination always plays an important role in vehicle development. The mechatronic brake system induces interfering noise that is transferred into the vehicle interior, differing from vehicle to vehicle and maneuver to maneuver. Supposedly, a wide frequency range, numerous components, and various branched transfer paths in the physical domains of airborne, structure-borne, and fluid-borne sound are involved in the noise propagation.

A wide-ranging investigation into the sensitivity of the hybrid RANS-LES based OpenFOAM CFD process at Audi was undertaken. For a range of cars (A1, TT, Q3 & A4) the influence of the computational grid resolution, turbulence model formulation and spatial & temporal discretization is assessed. It is shown that SnappyHexMesh, the Cartesian-prismatic built-in OpenFOAM mesher is unable to generate low y+ grids of sufficient quality for the production Audi car geometries. For high y+ grids there was not a consistent trend of additional refinement leading to improved correlation between CFD and experimental data. Similar conclusions were found for the turbulence models and numerical schemes, where consistent improvements over the baseline setup for all aerodynamic force coefficients were in general not possible. The A1 vehicle exhibited the greatest sensitivity to methodology changes, with the TT showing the least sensitivity.

The electrification of the powertrain and the thereto related recuperation of the electric engine saves the energy in the battery and thus reduces the thermally dissipated brake energy, which leads to lower brake rotor temperatures compared to combustion engine vehicles (ICEVs). These new conditions enable to reconsider brake disc concepts. Including lightweight design in heavy battery electric vehicles (BEVs) and the increasingly reliant corrosion resistance of brake rotors, Aluminum is a promising approach for new brake disc concepts. In the past, Aluminum brake disc concepts have already been deployed. For instance Aluminum Metal-Matrix Composite (Al-MMC) concepts in the Lotus Elise S1 and on the rear axle of the Volvo V40 [1]. The presented concept is a different approach and separates the friction system from the bulk Aluminum brake disc, achieved by coating of the friction rings.

Non-exhaust emissions in general and brake particle emissions in particular have become very relevant during the last years. Even if many investigations and efforts are under progress, no common test standards exist so far. Many mechanisms and possible impacts are not fully understood either. Hence, the authors continued their investigations by using an already refined and proved test setup, which is the base for further characterizations and enhancements. The presented studies include the characterization of three different friction couples (using the same brake system) for two different test cycles (namely a modified AK Master and a WLTP) in terms of particle number concentration. Additionally, the major differences of the modified AK Master and the WLTP are investigated and analyzed. Finally, results of particle mass characterizations introduced. A brief summary and some conclusions are presented in the final chapter.

The engine development process has been enhanced significantly by virtual engineering methods during the last decades. In terms of in-cylinder flow field, charge flow and combustion modelling, 3D-CFD (three dimensional) simulations enable detailed analysis and extended investigations in order to gain additional knowledge about design parameters. However, the computational time of the 3D-CFD is an obvious drawback that prevents a reasonable application for extensive analysis with varying speed, load and transient conditions. State-of-the-art 0D (zero dimensional) approaches close the gap between the demand of high computational efficiency and a satisfying accordance with experimental data. Recent improvements of phenomenological combustion approaches for gasoline spark ignition engines deal with the consideration of detailed flow parameters, the accuracy of the laminar flame speed calculation and the prediction of the knock limit.

New human-machine interfaces are the direct result of digitalization. So also in lighting, new constellations have to be taken into account when looking to the possibilities of giving additional informations to the driver. Lighting and furthermore information given by light is a clear preference during nighttime driving. The global interest in standardization of light driven messages from autonomous vehicles to other traffic participants has opened new research needs in order to prepare full view on such new human-machine interface. In Europe, GTB (Group de Travail de Bruxelles) has established a working group dedicated to this topic. In order to provide a complete picture of the effects of digital light, the question of additional glare contribution by digital informations, i.e. extra projected light in form of patterns, symbols or areas was addressed in this research study. This article will show the investigations on wet and dry road glare while driving with digital informations.