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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.

The number of vehicles in world has been steadily increasing over the years. Asia Pacific is blessed to have the fastest growth rate in the world, with China experiencing over 20% vehicle production growth in the recent and coming years. As India jumps on this explosive bandwagon which could see growth rates higher than China, there is a need to understand the environmental and cost aspects arising from the vast increase of automobiles. The need to protect the environment, combined with the limited resource of oil, has led to the need for more fuel-efficient vehicles with intelligent engine and transmission control systems. This paper/presentation will look into the tough emissions regulations, lower CO2 requirement, different fuels and their efficiency, alternative fuel and the infrastructure to support such a paradigm shift, cost to achieve the desired, and GEMS-K1 (Gasoline Engine Management System - Kit 1) as a solution to meet some of the issues mentioned.

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.

Fuel efficiency and clean combustion engine versus high engine performance - which will increase up to factor 10 in the next 5 years - with less engine displacement are driving more complex engine control systems in today's and future vehicles. The challenge is not only to design a perfect engine, but also to incorporate the right semiconductors. Beside this demand on high sophisticated electronics the demand on cost reduction - especially for small cars - is one driving factor for a smart partitioning. Infineon offers sensors, microcontrollers and power semiconductors for today's engine management platforms and therefore owns the right technologies to manufacture those devices. This opens up the possibility to integrate more functionality in less devices as in today's partitioning or to define electronics to simplify complex control strategies and to optimize the performance of each device.

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.

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.

Glare-free high beams are a consistent enhancement of adaptive headlight systems for vehicles with advanced driver assist systems. A prerequisite for these are camera-based systems with the ability to recognize and classify objects such as vehicles in front or oncoming vehicles when driving at night. These objects can then be dynamically masked out of the high beam of the specially designed headlights. Since we are talking about moving objects, it is essential for the high beam to be continuously and dynamically adapted. This paper describes a modular LED matrix system for dynamically adjusting a glare-free and continuously active high beam. The main focus was on the modularity of the system and the optimization of the thermal properties of an LED matrix in order to ensure that operation was reliable under the harsh environmental conditions inside a headlight. Specific control electronics and different interconnection methods were examined.

The trend towards even more sophisticated driver assistance systems and growing automation of driving sets new requirements for the robustness and availability of the involved automotive systems. In case of an error, today it is still sufficient that safety related systems just fail safe or silent to prevent safety related influence of the driving stability resulting in a functional deactivation. But the reliance on passive mechanical fallbacks in which the human driver taking over control, being inevitable in such a scenario, is expected to get more and more insufficient along with a rising degree of driving automation as the driver will be given longer reaction time. The advantage of highly or even fully automated driving is that the driver can focus on other tasks than controlling the car and monitoring it’s behavior and environment.