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This paper makes a contribution toward a more efficient chassis durability process for the development of passenger cars, in which the simulation of relevant load data is a time-consuming part. This is especially due to the full vehicle model complexity which is usually determined by the demands of rough road simulations. However, for the load calculation on a racetrack, time saving model approaches that are more simplified might be sufficient. Our investigation comprises two levels of vehicle model complexity: one with all chassis parts modeled in a multibody system environment and one characteristic curve based model in an internal simulation environment. Both approaches consider an original chassis control system as a Software-in-the-Loop model. By the evaluation of real-world experiments the main influence factors in terms of durability are demonstrated. With the help of those highly sensitive durability criteria the measurement and simulation results are then compared.

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.

In this paper experimental results of a medium duty single cylinder research engine with spark ignition are presented. The engine was operated with stoichiometric natural gas combustion and additional charge dilution by means of external and cooled exhaust gas recirculation (EGR). The first part of this work considers the benefits of cooled EGR on thermo-mechanical stress of the engine including exhaust gas temperature, cylinder head temperature, and knock behaviour. This is followed by the analysis of the influence of cooled EGR on the heat release rate. In this context the impact of fuel gas composition is also under investigation. The influence of increasing EGR on fuel efficiency, which is caused by a changed combustion process due to higher fractions of inert gases, is shown in this section. By application of different pistons a relationship between the piston bowl geometry and the flame propagation has been demonstrated.

The number of full electric and hybrid electric vehicles is rapidly growing [1][2][3]. The new technologies accompanying this trend are increasingly becoming a focal point of interest for rescue services. There is much uncertainty about the right techniques to free trapped occupants after an accident. The same applies to vehicle fires. Can car fires involving vehicles with a lithium ion traction battery be handled in the same way as conventional vehicle fires? Is water the right extinguishing agent? Is there a risk of explosion? There are many unanswered questions surrounding the topic of electric vehicle safety. The lack of information is a breeding ground for rumours, misinformation and superficial knowledge. Discussions on various internet platforms further this trend. Tests were conducted on three lithium ion traction batteries, which were fuel-fired until burning on their own. The batteries were then extinguished with water, a surfactant and a gelling agent.

Rising oil prices and increasing strict emission legislation force vehicle manufacturers to reduce fuel consumption of future vehicles. In order to meet this target, the process of converting fuel into useable energy and the use of this energy by the different energy-consuming vehicle's subsystems have to be examined. Vehicles' subsystems consist of energy-supplying, energy-consuming, and in some cases energy-storing components. Due to the high complexity of these systems and their interaction, optimization of their energy efficiency is a challenging task. By introducing individual operational strategies for each subsystem, it is possible to increase the energy efficiency for a specific function. To further improve the vehicle's overall energy efficiency, holistic control strategies are introduced that distribute the energy between the subsystems intelligently.

NH₃/urea SCR is a very effective and widely used technology for the abatement of NOx from diesel exhaust. The SCR mechanism is well understood and the catalyst behavior can be predicted by mathematical models - as long as operation above the temperature limit for AdBlue® injection is considered. The behavior below this level is less understood. During the first seconds up to minutes after cold start, complete NOx abatement can be observed over an SCR catalyst in test bench experiments, together with a significant increase in temperature after the converter (ca. 100 K). In this work these effects have been investigated over a monolith Cu-zeolite SCR catalyst. Concentration step experiments varying NO, NO₂ and H₂O have been carried out in lab scale, starting from room temperature. Further, the interaction of C₃H₆ and CO with NOx over the SCR has been investigated.

In order to reduce fuel consumption in Fuel Cell Electric Vehicles, effective distribution of power demand between Fuel Cell and Battery is required. Energy management strategies can improve fuel economy by meeting power demand efficiently. This paper explains development of various energy management strategies for Fuel Cell Electric Vehicle with Lithium Ion Battery. Drive cycles used for optimization and analysis of the strategies are New European Drive cycles (NEDC), Japanese Drive cycles (JAP1015), City Drive cycles, Highway Drive cycles (FHDS) and Federal Urban Drive cycles (FUDS). All Fuel consumption and ageing calculations are done using backward model implemented in MATLAB/SIMULINK.

Aerodynamic design and thermal management are some of the most important tasks when developing new concepts for the flow around tractor-trailers. Today, both experimental and numerical studies are an integral part of the aerodynamic and thermal design processes. A variety of studies have been conducted how the aerodynamic design reduces the drag coefficient for fuel efficiency as well as for the construction of radiators to provide cooling on tractor-trailers. However, only a few studies cover the combined effect of the aerodynamic and thermal design on the air temperature of the under hood flow [8, 13, 16, 17, 20]. The objective of this study is to analyze the heat transfer through forced convection for a scaled Cab-over-Engine (CoE) tractor-trailer model with under hood flow. Different design concepts are compared to provide low under hood air temperature and efficient cooling of the sub components.

Digital or virtual prototyping by means of a multibody simulation model (MBS) is a standard part of the automotive design process. A high-fidelity model is built and often correlated against test data to increase its accuracy. Once built the MBS model can then be used for high fidelity analysis in ride comfort, handling as well as durability. Next to the MBS model, current industry practice is to develop a reduced degree of freedom model for the design and validation of control or intelligent systems. The models used in the control system design are required to execute in hardware-in-the-loop (HIL) simulations where it is necessary to run real-time. The reason for the creation of the reduced degree of freedom models so far has been that the high-fidelity or off-line model does not execute fast enough to be used in an HIL simulation.

The continuously integration of electrics and electronics (EE) in the last decades is one of the main key drivers for innovation and business success of the Automotive OEMs. This is also applicable for truck manufacturers. On the other side factors like the rising vehicle complexity, number of variants and the warranty costs for EE issues are increasing the pressure on the engineering teams responsible for the mechatronic systems. To address these issues one of the key activities in the European market (focus on Germany) during the last decade was to introduce industry-wide standards for the data transfer of wiring harness data between OEM and harness supplier. In this paper the benefits and technical background of using the standards KBL and KOMP formats within the MB-Trucks brand will be presented. Moreover the role of the Information Technology (IT) will be explained in detail.

Beginning in 2010, Daimler's well-known Diesel Sprinter van has to fulfill the new and clearly tighter NOx emission standards of NAFTA10 (EPA, CARB). This requires an integrated approach of further engine optimizations and the implementation of an innovative exhaust aftertreatment technology. The goal was to develop an overall concept which meets simultaneously the tightened emission standards (including OBD limits) and the increasing customer demands of more power and torque without losing the high fuel efficiency of the small and highly efficient 3-liter V6 diesel engine OM642, which already has been installed in the NAFTA07 Sprinter. In the early stages of the concept phase, the most appropriate NOx aftertreatment technology and certification form (engine or vehicle) had to be selected for this specific vehicle class in the van segment with enhanced requirements to durability, economical efficiency and specific driving behavior.

The economic challenges and environmental imperatives facing the trucking and automobile industries today all point to a pressing need to improve fuel efficiency. Due to increasing volatility of fuel supplies, prices and a growing interest in reducing greenhouse gas emissions, fuel efficiency has taken on new urgency. In the long-haul trucking industry this is especially important given the fact that fuel accounts for a significant share of fleet operating costs. To this end Daimler and NAVTEQ have developed a system to improve fuel economy and reduce CO₂ emissions through the integration of digital map data into Advanced Driver Assistance Systems or ADAS. Digital road map attributes, especially road slope have been demonstrated to enable powertrain controls to anticipate road inclination changes and use this information to predictively enhance load management optimization versus the reactive approach afforded by current technology.

In this study the numerical simulation of the flow through an alternator inside an engine compartment of a passenger car is investigated. Specifically the interaction of the flow through the alternator with the flow through the engine compartment is explored in detail. The results are compared with a corresponding numerical simulation of an alternator in a surrounding of a test facility and with a numerical simulation of the flow through an engine compartment without taking into account the internal flow through the alternator. Finally the air temperature near the alternator and also the temperature of some components inside the alternator are compared with experimental values measured during a typical load case used for the thermal protection of the passenger car.

Tire mark analysis is an important factor in accident reconstruction. A precise determination of pre- and postcrash speeds as well as longitudinal and lateral accelerations from tire marks contributes significantly to a reliable accident reconstruction. Continuous advancements in tire and vehicle technology – in particular with respect to modern control systems such as anti-lock braking systems (ABS) – raises the question what role tire marks play in accident reconstruction today. Moreover, this accompanies the question to what extent potential interventions by vehicle control systems such as the electronic stability program (ESP®) resp. the electronic stability control (ESC) can be identified in a tire mark. The widespread use of these systems today makes them increasingly important in accident reconstruction.

A numerical model for a diesel oxidation catalyst (DOC) is presented. It is based on a spatially 1D, physical and chemically based modeling of the relevant processes within the catalytic monolith. A global reaction kinetic approach has been chosen to describe the chemical reactions. Water condensation and evaporation was also considered, in order to predict the cold start behavior. Reaction kinetic parameters have been evaluated from a series of laboratory experiments. A correlation between the kinetic parameters and the noble metal loading was developed. The model was used in combination with a SCR-Model to study the influence of changes of noble metal loading and DOC volume on the overall transient NOx performance of a DOC+DPF+SCR system.

While the market share for diesel engines for LD vehicles in Europe has grown continuously in the past years, the market share in North America is still negligible. Until now, it has been possible to fulfill the limits for nitrogen oxides (NOx) both in Europe and in North America by engine measures alone, without using an active NOx aftertreatment system. With the introduction of Tier II Bin 8 and Tier II Bin 5 emissions legislation in the US in 2007, most new diesel applications will now require NOx aftertreatment. One of the possible technologies for the reduction of nitrogen oxides in lean exhaust gas is the NOx storage catalyst which has become the generally-accepted choice for engines with gasoline direct injection systems and which is also utilized in the current diesel Bluetec I systems from Daimler. For heavier applications urea-SCR is the preferred technology to fulfill NOx legislation limits.