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Filtration of diesel and gasoline fuel in automotive applications is affected by many external and internal parameters, e.g. vibration, temperature, pressure, flow pulsation, and engine start-stop. Current test procedures for automotive fuel filters, proposed by most of the researchers and organizations including Society for Automotive Engineers (SAE) and International Organization for Standardization (ISO), do not apply the previously mentioned real-world-conditions. These operating conditions, which are typical for an automotive fueling system, have a significant effect on fuel filtration and need to be considered for the accurate assessment of the filter. This requires the development of improved testing procedures that will simulate the operating conditions in a fuel system as encountered in the real world.

Stricter emissions legislation and growing demands for lower fuel consumption require significant efforts to improve combustion efficiency while satisfying the emission quality demands. Controlled Homogeneous Charge Compression Ignition (HCCI) combined with boosted air systems on gasoline engines provides a particularly promising, yet challenging, approach. Naturally aspirated (NA) HCCI has already shown considerable potential in combustion efficiency gains. Nevertheless, since the volumetric efficiency is limited in the NA HCCI operation range due to the hot residuals required to ignite the mixture and slow down reaction kinetics, only part-load operation is feasible in this combustion mode. Considering the future gasoline engine market with growing potentials identified in downsized gasoline engines, it becomes necessary to investigate the synergies and challenges of controlled, boosted HCCI.

Due to the increasingly stricter emission legislation and growing demands for lower fuel consumption, there have been significant efforts to improve combustion efficiency while satisfying the emission requirements. Homogeneous Charge Compression Ignition (HCCI) combined with turbo/supercharging on gasoline engines provides a particularly promising and, at the same time, a challenging approach. Naturally aspirated (n.a.) HCCI has already shown a considerable potential of about 14% in the New European Driving Cycle (NEDC) compared with a conventional 4-cylinder 2.0 liter gasoline Port Fuel Injection (PFI) engine without any advanced valve-train technology. The HCCI n.a. operation range is air breathing limited due to the hot residuals required for the self-ignition and to slow down reaction kinetics, and therefore is limited to a part-load operation area.

The transition from the multi-component ABS2 design to the one housing concept of ABS5.0 represented a significant step in improving the ABS unit. ABS5.3 is the successor of ABS5.0 to achieve a highly compact, light weight inexpensive design, for the broad use of ABS in all passenger cars and light trucks. New technologies applied are the staking technique for hydraulic components, the use of microhybrid electronics design and solenoid coils being integrated within the attached electronic control unit. The unit can be manufactured in global alliance achieved by simultaneous engineering, applying CAD, FE-analysis, flow calculation and simulation, noise analysis and quality assurance which includes FMEA, error simulation, durability tests and the dry testing concept. The ABS5.3 design can be easily expanded to Traction Control (ASR).

Environmental consciousness and tightening emissions legislation push the market share of electronic fuel injection within a dynamically growing world wide small engines market. Similar to automotive engines during late 1980's, this opens up opportunities for original equipment manufacturers (OEM) and suppliers to jointly advance small engines performance in terms of fuel economy, emissions, and drivability. In this context, advanced combustion system analyses from automotive engine testing have been applied to a typical production motorcycle small engine. The 125cc 4-stroke, 2-valve, air-cooled, single-cylinder engine with closed-loop lambda-controlled electronic port fuel injection was investigated in original series configuration on an engine dynamometer. The test cycle fuel consumption simulation provides reasonable best case fuel economy estimates based on stationary map fuel consumption measurements.

In order to meet future requirements for emission reduction and fuel economy a variety of concepts are available for gasoline engines. In the recent past new pathways have been found using alternative fuels and fuel combinations to establish cost optimized solutions. The presented concept for a SI-engine consists of combined injection of gasoline and hydrogen. A hydrogen enriched gas mixture is being injected additionally to gasoline into the engine manifold. The gas composition represents the output of an onboard gasoline reformer. The simulations and measurements show substantial benefits to improve the combustion process resulting in reduced cold start and warm up emissions and optimized part load operation. The replacement of gasoline by hydrogen-rich gas during engine start leads to zero hydrocarbons in the exhaust gas.

In the low-cost segment for 2-Wheelers legislative, economic and ecologic considerations necessitate a reduction of the emissions and further improvement in fuel consumption. To reach these targets, the commonly used carburetors are being replaced by engine management systems (EMS). One option to provide these systems for acceptable and attractive system costs is to save a sensor device and to substitute its measure by an estimation value. In many motorcycles the rotor of the vehicle's alternator is rigidly attached to the crankshaft. Therefore, the voltage and current signals of the alternator contain information about the engine's speed, which can be retrieved by evaluating these electric signals. After further processing of this information inside the electronic control unit (ECU), the absolute crankshaft position can be obtained. A high-resolution speed signal without mechanical distortions like tooth errors is gained, whose signal quality equals the one of a common speed sensor.

The present paper concentrates on the option of catalytic autothermal reforming of gasoline for fuel cell applications. Major parameters of this process are the “Steam to Carbon Ratio” S/C and the air to fuel ratio λ. Computations assuming thermodynamic equilibrium in the autothermal reactor outlet (ATR) were carried out to attain information about their proper choice, as failure in adjusting the parameters within narrow limits has severe consequences on the reforming process. In order to quantify velocity distribution just ahead the catalyst and to evaluate mixing uniformity we designed an ATR featuring an optical access: Thus flow visualization using PIV (Particle Image Velocimetry) and LIF (Laser Induced Fluorescence) technique is possible. Preliminary PIV-results are presented and compared with CFD computations (Computational Fluid D ynamics).

The worldwide stricter emission legislation and growing demands for lower fuel consumption require for significant efforts to improve combustion efficiency while satisfying the emission quality demands. Homogeneous Charge Compression Ignition (HCCI) on gasoline engines provides a particularly promising and, at the same time, challenging approach, especially regarding the combustion mode switch between spark-ignited (SI) and gasoline HCCI mode and vice-versa. Naturally aspirated (n.a.) HCCI shows considerable potential, but the operation range is air breathing limited due to hot residuals required for auto-ignition and to slow down reaction kinetics. Therefore it is limited to part-load operation. Considering the future gasoline engine market with growing potentials identified on downsized gasoline engines, it is imperative to investigate the synergies and challenges of boosted HCCI.

Commercial vehicles must convey people and goods safely and reliable, irrespective of the weather and road conditions. The ABS safety braking systems are an essential prerequisite for fulfillment of this primary task. ABS has been used in European commercial vehicles since 1981. Today there are already fittet as standard in buses to some extend. The contribution to increasing road safety is causing the European lawmakers to make ABS statutory for commercial vehicles and to make it part of their compulsory equipment. Suitable anti-lock braking systems and closed loop configurations for commercial vehicles are demonstrated by theoretical observations and technical driving trials, their axlespecific and closed-loop control characteristics are highlighted.

The paper begins with an overview of the history of ABS for commercial vehicles followed by a brief description of the technology of the BOSCH ABS at the time it went into mass production in 1981. Subsequently it describes the field experiences with ABS including the experiences of drivers and operators. These experiences are reflected in the equipment which BOSCH offers today. Additional functions such as ASR (traction control) have been integrated. The paper provides an overview of the functions available today and their implementation. The paper concludes with a discussion on potential continued developments and an attempt to describe the systems which will be required by the mid 9os.

Current vehicle concepts necessitate the multiple measurement of several variables required by separate electronic systems in the motor vehicle. There is the need to make sensors bus capable by the incorporation of electronic components in new definition concepts, in other words to make them multiply usable. Such bus concepts are at the present time taking concrete shape. The step of introducing electronics - especially digital - to the measuring point may simultaneously be used to considerably improve utilization of the information content of sensor structures using means of indivdual, digital correction to a greater level than has until now been technically possible. There remains the demand for high stability and reproducibility of the sensor properties over time. These signal preprocessing and information condensation processes on the spot also satisfy the need to relieve the central control units.

With its origin in the process industry, the IEC 61508 „Functional safety of electrical/electronic/programmable electronic safety-related systems” is not fully applicable in the automotive industry, forcing the automotive industry to work on an automotive specific adaptation (ISO 26262 “Functional Safety – Road Vehicles”). This ISO 26262 describes an ideal development process that starts from scratch. In reality development activities are often split locally and in time. This can only be handled with a world wide standard as a basis of a common approach, wide enough to give enough freedom to adapt to diverse boundary conditions, but tight enough to hinder local interpretations to be that far, that a complete safety case becomes impossible. Therefore a strict world-wide standard which allows compatible interpretations is mandatory.

Due to its high number of free parameters, the new generation of gasoline engines with direct injection require an efficient calibration process to handle the system complexity and to avoid a dramatic increase in calibration costs. This paper presents a concept of specific toolboxes within a standardized and automated calibration environment, supporting the complexity of GDI engines and establishing standard procedures for distributed development. The basic idea is the combination of a new and more efficient online DoE approach with the automatic and adaptive identification of the region of interest in the high dimensional parameter space. This guarantees efficient experimental designs even for highly non-linear systems with often irregularly shaped valid regions. As the main advantage for the calibration engineer, the new approach requires almost no pre-investigations and no specific statistical knowledge.

This address presents the ongoing development of the commercial-vehicle braking system, over and beyond ABS/ASR, towards a brake by wire system (electronically controlled braking system ELB) with pressure-regulating circuit and additional functions. Following the discussion and selection of various concepts, we will present different versions with individual and combined components for the towing vehicle and for the trailer. The safety concept of a pneumatic back-up circuit will be dealt with, as well as the communication through data bus (CAN) both within the braking system itself and with other vehicle systems. The improvement possibilities inherent in ELB will be detailed, with the emphasis on increasing road and traffic safety, on reducing operating costs, and on future vehicle-guidance functions.

To meet future CO₂ emissions limits and satisfy the bounds set by exhaust gas legislation reducing the engine displacement while maintaining the power output ("Downsizing") becomes of more and more importance in the SI engine development process. The total number of cylinders per engine has to be reduced to keep the thermodynamic disadvantages of a small combustion chamber layout as small as possible. Doing so new challenges arise concerning the mechanical design, the design of the combustion system concept as well as strategies maintaining a satisfying transient torque behavior. To address these challenges a turbocharged 2-cylinder SI engine was designed for research purposes by Weber Motor GmbH and Robert Bosch GmbH. The design process was described in detail in last year's paper SAE 2012-01-0832. Since the engine design is very modular it allows for several different engine layouts which can be examined and evaluated.

The fuel spray behavior in the near nozzle region of a gasoline injector is challenging to predict due to existing pressure gradients and turbulences of the internal flow and in-nozzle cavitation. Therefore, statistical parameters for spray characterization through experiments must be considered. The characterization of spray velocity fields in the near-nozzle region is of particular importance as the velocity information is crucial in understanding the hydrodynamic processes which take place further downstream during fuel atomization and mixture formation. This knowledge is needed in order to optimize injector nozzles for future requirements. In this study, the results of three experimental approaches for determination of spray velocity in the near-nozzle region are presented. Two different injector nozzle types were measured through high-speed shadowgraph imaging, Laser Doppler Anemometry (LDA) and X-ray imaging.

The ongoing changes in the development of new power trains and the requirements due to driver assistance systems and autonomous driving could be the enabler for completely new brake system configurations. The shift in the brake load collective has to be included in the systems requirements for electric vehicles. Many alternative concepts for hydraulic brake systems, even for decentralized configurations, can be found in the literature. For a decentralized system with all state of the art safety functionalities included, four actuators are necessary. Therefore, the single brake module should be as cost-effective as possible. Previous papers introduced systems which are for example based on plunger-like concepts, which are very expensive and heavy due to the needed gearing and design. In this paper a comparison between a state of the art hydraulic brake system using an electromechanical brake booster, and a completely new decentralized hydraulic brake concept is presented.

For electric vehicles the ability for regenerative braking reduces the use of friction brakes. Particularly on the rear axle of vehicles with reduced dynamic requirements such as urban vehicles, this can offer a potential for downsizing or, in extreme cases, even the elimination of the friction brakes on the rear axle. Due to the fact that the rear axle service brakes also represent the typical parking brake location in SoA (State-of-Art) vehicles, a rigorous rethinking of the parking brake concept is necessary to incorporate safe vehicle standstill management for such novel brake system topology. This research study introduces a novel parking brake design that covers SoA but also legal requirements while retaining potentials associated with the elimination of the rear service brakes such as cost and packaging.