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In addition to the low and high beam functions, some modern headlamps also have the option of switching on only section of the high beam. The so-called adaptive high beam is intended to increase the detection distance of objects and through that drastically improve the road safety. At the same time, this function does not increase the glare for oncoming or preceding traffic. This is enabled through switching the different segments of the high beam on or off, depending on which and where other road users are recognized by the front camera. This massively increases the use of the high beam, thus increasing road safety. In this study, the increase in the detection distance of objects on a straight line is statically investigated with a test person study. Furthermore, the glare of each of these three light functions is observed.

The current automotive electronic and electrical (EE) architecture has reached a scalability limit and in order to adapt to the new and upcoming requirements, novel automotive EE architectures are currently being investigated to support: a) an Ethernet backbone, b) consolidation of hardware capabilities leading to a centralized architecture from an existing distributed architecture, c) optimization of wiring to reduce cost, and d) adaptation of service-oriented software architectures. These requirements lead to the development of Zonal EE architectures as a possible solution that require appropriate adaptation of used security mechanisms and the corresponding utilized hardware trust anchors. 1 The current architecture approaches (ECU internal and in-vehicle networking) are being pushed to their limits, simultaneously, the current embedded security solutions also seem to reveal their limitations due to an increase in connectivity.

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.

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.

The acoustic trim components play an essential role in NVH behavior by reducing both the structure borne and airborne noise transmission while participating to the absorption inside the car. Over the past years, the interest for numerical solutions to predict the noise transmission through trim packages has grown, leading to the development of dedicated CAE tools. The incrementally restrictive weight and space constraints force today CAE engineers to seek for optimized trim package solution. This paper presents a two-steps process which aims to reduce the structure borne road noise due to floor panel using a coupled simulation with MSC NASTRAN and Actran. The embossment of the supporting steel structure, the material properties of porous layers and the thickness of visco-elastic patches are the design variables of the optimization process.

The aerodynamic development of the new Audi Q5 (released in 2017) is described. In the course of the optimization process a number of different tools has been applied depending on the chronological progress in the project. During the early design phase, wind tunnel experiments at 1:4 scale were performed accompanied by transient DES and stationary adjoint simulations. At this stage the model contained a detailed underbody but no detailed engine bay for underhood flow. Later, a full scale Q5 model was built up for the aerodynamic optimization in the 1:1 wind tunnel at Audi AG. The model featured a detailed underbody and engine bay including original parts for radiators, engine, axles and brakes from similar vehicles. Also the 1:1 experiments were accompanied by transient DES and stationary adjoint simulations in order to predict optimization potential and to better understand the governing flow.

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.

The aim of this investigation is the improvement of the lateral vehicle dynamics by optimizing the rim width. For that purpose, the rim width is considered as a development tool and configured with regard to specified targets. Using a specifically developed method of simulation, the influence of the rim width is analysed within different levels - starting at the component level “tyre” and going up to the level of the whole vehicle. With the help of substantial simulations using a nonlinear two-track model, the dimensioning of the rim width is brought to an optimum. Based on both, tyre and vehicle measurements, the theoretical studies can be proved in practice. As a result, the rim width has a strong influence on the behaviour of the tyre as well as on the overall vehicle performance, which emphasises its importance as a potential development tool within the development of a chassis.

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 optimization of the flow field around new vehicle concepts is driven by aerodynamic and thermal demands. Even though aerodynamics and thermodynamics interact, the corresponding design processes are still decoupled. Objective of this study is to include a thermal model into the aerodynamic design process. Thus, thermal concepts can be evaluated at a considerably earlier design stage of new vehicles, resulting in earlier market entry. In a first step, an incompressible CFD code is extended with a passive scalar transport equation for temperature. The next step also accounts for buoyancy effects. The simulated development of the thermal boundary layer is validated on a hot flat plate without pressure gradient. Subsequently, the solvers are validated for a heated block with ground clearance: The flow pattern in the wake and integral heat transfer coefficients are compared to wind tunnel simulations. The main section of this report covers the validation on a full-scale production car.

In current research projects such as "Vehicle to Grid" (V2G), "Vehicle to Building" (V2B) or "Vehicle to Home" (V2H), plug-in vehicles are integrated into stationary energy systems. V2B or V2H therefore stands for intelligent networking between vehicles and buildings. However, in these projects the objective is mostly from a pure electric point of view, to smooth the load profile on a household level by optimized charging and discharging of electric vehicles. In the present paper a small energy system of this kind, consisting of a building and a vehicle, is investigated from a holistic point of view. Thermal as well as electrical system components are taken into account and there is a focus on reduction of overall energy consumption and CO₂ emissions. A predictive energy management is presented that coordinates the integration of a plug-in hybrid electric vehicle into the energy systems of a building. System operation is optimized in terms of energy consumption and CO₂ emissions.

Electric vehicles differ from conventionally powered vehicles in terms of many characteristics that are directly relevant to the customer. The most evident ones are the total driving range, which is limited by the battery capacity, and the different acceleration behavior, which is directly influenced by the electric motor's torque characteristics. Furthermore, there are many other vehicle characteristics, such as lateral dynamics, that are also strongly influenced by electrification. For all customer-relevant vehicle characteristics, it is important to know the necessary and optimal fulfillments in order to plan and evaluate new electrified vehicle concepts. Correlation functions can be used to convert values for technical characteristics to normalized customer satisfaction fulfillments. To evaluate the quality of a vehicle concept during the development process, a parametric cost function is defined.

The presentation describes the aerodynamic development and optimization process of the three different new models of the Audi A6/A7 family. The body types of these three models represent the three classic aerodynamic body types squareback, notchback and fastback. A short introduction of the flow structures of these different body types is given and their effect on the vehicle aerodynamic is described. In order to achieve good aerodynamic performance, the integration into the development process of the knowledge about these flow phenomena and the breakdown of the aerodynamic resistance into its components friction- and pressure drag as well as the induced drag is very important. The presentation illustrates how this is realized within the aerodynamic development process at Audi. It describes how the results of CFD simulations are combined with wind tunnel measurements and how the information about the different flow phenomena were used to achieve an aerodynamic improvement.

Advanced thermal management systems in passenger cars present a possibility to increase efficiency of current and future vehicles. However, a vehicle integrated thermal management of the combustion engine is essential to optimize the overall thermal system. This paper shows results of an experimental heat flux analysis of a state-of-the-art automotive diesel engine with common rail injection, map-controlled thermostat and split cooling system. Measurements on a climatic chamber engine test bench were performed to investigate heat fluxes and energy balance in steady-state operation and during engine warm-up from different engine start temperatures. The analysis includes the influence of the operating point and operating parameters like EGR rate, injection strategy and coolant temperature on the engine energy balance.

The paper describes the aerodynamic development and optimization process of the three different new models of the Audi A6/A7 family. The body types of these three models represent the three classic aerodynamic body types squareback, notchback and fastback. A short introduction of the flow structures of these different body types is given and their effect on the vehicle aerodynamic is described. In order to achieve good aerodynamic performance, the integration into the development process of the knowledge about these flow phenomena and the breakdown of the aerodynamic resistance into its components friction- and pressure drag as well as the induced drag is very important. The paper illustrates how this is realized within the aerodynamic development process at Audi. It describes how the results of CFD simulations are combined with wind tunnel measurements and how the information about the different flow phenomena were used to achieve an aerodynamic improvement.

Diesel engines face difficult challenges with respect to engine-out emissions, efficiency and power density as the legal requirements concerning emissions and fuel consumption are constantly increasing. In general, for a diesel engine to achieve low raw emissions a well-mixed fuel-air mixture, burning at low combustion temperatures, is necessary. Highly premixed diesel combustion is a feasible way to reduce the smoke emissions to very low levels compared to conventional diesel combustion. In order to reach both, very low NOX and soot emissions, high rates of cooled EGR are necessary. With high rates of cooled EGR the NOX formation can be suppressed almost completely. This paper investigates to what extent the trade-off between emissions, fuel consumption and power of a diesel engine can be resolved by highly premixed and low temperature diesel combustion using injection nozzles with reduced injection hole diameters and high pressure fuel injection.

The SCR after treatment system is already in production for passenger car engines with a single exhaust system. In this case, the exhaust system has to be designed very carefully to optimize the Ammonia distribution on the catalyst and therefore the DeNOx potential. The application to V8 engines with two turbochargers delivering the gas into two separated DOC & DPF units is an additional challenge. This paper describes the different optimization steps of such an exhaust system and the tools used during this work. After a design phase to integrate the SCR system in the exhaust geometry, a first CFD study was conducted to evaluate the performance of the basic system using one or two urea injectors. An optimization of the connection of the two tubes, directly in front of the SCR catalyst, has been designed using further CFD calculations as well as a marker gas SF6 on a cold flow bench.

A catalyzed ceramic filter has been used on diesel engines for diesel particulate matter emission control. A key design criteria for a diesel particulate filter is to maximize DPF performance, i.e. low back pressure and compact size as well as near continuous regeneration operation. Based upon the modeling and deep understanding of material properties, a DPF system design has been successfully applied on a high performance diesel engine exhaust system, such as the Audi R10 TDI, the first diesel racing car that won the most prestigious endurance race in the world: the 24 hours of Le Mans in both 2006 and 2007. The design concept can be used for other materials and applications

The paper describes the integration of Complexity Management into the design cycle of an Automobile Manufacturer. It explains the reasons why most Automobile Manufacturers lack effective processes of dealing with complexity issues and introduces a holistic methodology for systematic and successful avoidance and control of unnecessary complexity. The paper provides an overview on the methods and tools necessary for the successful application of the above principle and is based on the experiences made with the implementation of the concept into the Audi AG product development process.

The following document offers insight into the work of the MOST Cooperation. Now that MOST is on the road, a short overview of five years of successful collaborative work of the partners involved and the results achieved will be given. Emphasis is put on the importance of a shared vision in combination with shared values as a prerequisite for targeted collaborative work. It is also about additional key success factors that led to the success of the MOST Cooperation. Your attention will be directed to the way the MOST Cooperation sets and achieves its goals. And you will learn about how the organization was set-up to support a fast progression towards the common goal. The document concludes with examples of recent work as well as an outlook on future work.