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The spatial distribution of internal exhaust gas recirculation (EGR) is evaluated in an optically accessible direct injection spark ignition engine using near infrared laser absorption to visualize the distribution of the H2O molecule. The obtained overall internal exhaust gas recirculation compares well to gas-exchange cycle calculations and the spatial distributions are consistent with those measured with inverse LIF. The experimental procedures described in this report are designed to be simple and rapidly implemented without the need to resort to unusual optical components. The necessary spectral data of the selected absorption line is obtained from the HITEMP database and is validated with prior experiments carried out in a reference cell. Laser speckle in the images is effectively reduced using a ballistic diffuser.

In the context of the energy transition, CO2-neutral solutions are of enormous importance for all sectors, but especially for the mobility sector. Hydrogen as an energy carrier has therefore been the focus of research and development for some time. However, the development of hydrogen combustion engines is in many respects still in the conception phase. Automotive system providers and engineering companies in the field of software development and simulation are showing great interest in the topic. In a joint project with the industrial partners Robert Bosch GmbH and AVL Germany, combustion in a H2-DI-engine for use in light-duty vehicles was methodically investigated using the CFD tool AVL FIRE®. The collaboration between Robert Bosch GmbH and the Institute for Mobile Systems (IMS) at Otto von Guericke University Magdeburg has produced a model study in which model approaches for the combustion of hydrogen can be analyzed.

Car Periphery Supervision (CPS) systems comprise a family of automotive systems that are based on sensors installed around the vehicle to monitor its environment. The measurement and evaluation of sensor data enables the realization of several kinds of higher level applications such as parking assistance or blind spot detection. Although a lot of similarity can be identified among CPS applications, these systems are traditionally built separately. Usually, each single system is built with its own electronic control unit, and it is likely that the application software is bound to the controller's hardware. Current systems engineering therefore often leads to a large number of inflexible, dedicated systems in the automobile that together consume a large amount of power, weight, and installation space and produce high manufacturing and maintenance costs.

Environmental and economical reasons have led to an increased interest in the usage of alternative fuels for combustion engines. To clarify the influence of these so-called future fuels on engine performance and emissions it is mandatory to understand their effect on spray formation. Usually this is done by performing various spray experiments with potential future fuels which are available for research purposes today. Due to the multitude of possible future fuels and therefore the uncertainty of their properties and their influence on spray formation a more general approach was chosen in the present study. The possible range of physical properties of future fuels for diesel engines was identified and more than twenty different fluids with representative properties, mostly one-component chemicals, were chosen by means of design of experiment (DoE).

The correct timing of the diesel injection pump on engine is of major importance for all functions of the engine and for its exhaust emissions, during production pass off as well as in the field. Within the diesel service workshops a variety of devices exist to test the timing of the injection pump on engine. Most of them operate by clamp-on transducer being fitted to the injection pipe. A large uncertainty exists concerning the accuracy of such timing systems. Most diesel engine manufacturers do not have confidence in the timing devices capability and, therefore, do not recommend their usage. A working group within the International Organization for Standardization (ISO) adopted a method for the validation of these measurement systems, which usually is used to judge the capability of measurement gauges for industrial production processes.

A new combustion pressure sensor (CPS) for advanced engine management is presented, which is designed to carry out the functions: misfire detection, knock control, ignition control, camshaft phase detection and engine roughness control. For small size and high accuracy at a reasonable cost the piezoresistive effect, which is realized within an integrated circuit device and delivers low impedance output signals, has been chosen. Due to the optimized sensor housing, membrane and force transfer design, the sensor shows little offset drift when affected by flame front and environmental thermal stress. This paper describes the CPS and its performance in comparison with a well-known highly accurate reference sensor.

The contribution presents a new data driven modeling approach for diesel HCCI combustion. Input parameters of the combustion model are external actuating variables as for example the start of injection. The model incorporates experimental data of the engine in HCCI mode, in the standard diesel mode and in the transition region between both modes. New disclosed dependencies between characteristic values of the cylinder pressure and the fuel burn rate are used to linearize the combustion model for a given operating point. In this paper the validation of the combustion model is discussed based on dynamic measuring data of the urban part of the NEDC. Finally, the combustion model is integrated in a zero-dimensional diesel engine model.

The functionality of engine management systems has grown rapidly over the last few years. The paper presents a new Motronic concept, the engine management control M3. The Motronic family M3 is a modular design destined to control engines with up to eight cylinders individually. The main features of this system and the ECU's concept are discussed.

This paper describes a new system for early detection of tripped rollover crashes. The main goal of this system is to improve the protection of restraint devices, such as curtain window bags, in these rollover situations. This is achieved by a new rollover sensing (RoSe) algorithm in the airbag controller which produces a very early and robust deployment decision. Based on the analysis of tripped rollover test data, this paper shows how improved rollover sensing performance can be achieved by considering information about the vehicle's driving state before the rollover occurs. The results of this new approach are discussed in terms of deployment times. Finally a combined active and passive safety system architecture for the realization of the approach is suggested.

The emission of particulate matter from future GDI engines has to be optimized, to comply with more stringent emission standards such as EU6. Therefore, the mechanisms responsible for the formation of particles have to be analyzed in detail. The understanding of the in-cylinder processes, necessary for this purpose, can only be achieved by a complementary use of optically accessible single-cylinder engines as well as the numerical simulation. This however leads to great demands on the 3D flow simulation. In this paper the complete CFD approach, incorporating a detailed description of the entire underlying model chain is shown. Particularly the wall surface temperature and the temperature drop due to the interaction with liquid fuel spray were identified as important parameters influencing the spray-wall interaction and thus also the particulate emissions. Nevertheless, in conventional CFD models, the spray cooling cannot be captured because of an assumed constant wall temperature.

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.

Particulate emissions from Gasoline Direct Injection (GDI) engines have been an important topic of recent research interest due to their known environmental effects. This review paper will characterise the influence of different gasoline direct injection fuel systems on particle number (PN) emissions. The findings will be reviewed for engine and vehicle measurements with appropriate driving cycles (especially real driving cycles) to evaluate effects of the fuel injection systems on PN emissions. Recent technological developments alongside the trends of the influence of system pressure and nozzle design on injector tip wetting and deposits will be considered. Besides the engine and fuel system it is known that fuel composition will have an important effect on GDI engine PN emissions. The evaporation qualities of fuels have a substantial influence on mixture preparation, as does the composition of the fuel itself.

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.

Antilock Braking Systems (ABS) and Traction Control Systems (ASR) should ensure maximum stability and steerability even under extreme driving conditions. Since high performance systems additionally improve brake distance and traction within the given physical limits, every vehicle equipped with ABS and ASR offers considerably higher active safety. ABS was introduced into the market by the Robert Bosch GmbH more than ten years ago, and more than 3 million systems have been produced by the end of 1988. Volume production of ASR began in 1987. This paper describes several high-, medium-, and low performance concepts and compares them with regard to safety and performance. Although it seems to be nearly impossible to define a cost/benefit ratio between monetary values and safety, our purpose here is to identify further development strategies through the use of a decision matrix.

In 1978, Bosch was the first supplier on the market to offer full-function antilock braking systems. In 1993, six years will have passed since Bosch delivered the first traction control system for passenger cars. In the meantime, a considerable amount of experience has been gained through ongoing development and testing. This experience enabled us to define the requirements for directional stability, optimum control strategy, maximum usage of the entire spectrum of drive torque intervention possibilities, and optimized hydraulics for automatic brake intervention. The result is Bosch ABS/ASR5, which in now being introduced to the market. This new ABS/ASR family is designed in modules, which offers high flexibility in function and assembly. Systems are available with traction improvement, or with optimized directional stability and traction. Each version is adapted to the needs of the vehicle drive layout, and adaptable to customer requirements.

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).

Closed loop vehicle control comprising of the driver, the vehicle and the environment is now achieved by the automatic wheel slip control combination of ABS and ASR. To improve directional control during acceleration, the Robert Bosch Corporation has introduced five ASR-Systems into series production. In one system, the electronic control unit works exclusively with the engine management system to assure directional control. In two other systems, brake intervention works in concert with throttle intervention. For this task, it was necessary to develop different highly sophisticated hydraulic units. The other systems improve traction by controlling limited slip differentials. The safety concept for all five systems includes two redundant micro controllers which crosscheck and compare input and output signals. A Traction Control System can be achieved through a number of torque intervention methods.

AUTOSAR (AUTomotive Open System ARchitecture) is a worldwide standard for automotive basic software in line with an architecture that eases exchange and transfer of application software components between platforms or companies. AUTOSAR provides the standardized architecture together with the specifications of the basics software along with the methodology for developing embedded control units for automotive applications. AUTOSAR matured over the last several years through intensive development, implementation and maintenance. Two main releases (R3.2 and R4.0) represent its current degree of maturity. AUTOSAR is driven by so called core partners: leading car manufacturers (BMW, Daimler, Ford, GM, PSA, Toyota, Volkswagen) together with the tier 1 suppliers Continental and Bosch. AUTOSAR in total has more than 150 companies (OEM, Tier X suppliers, SW and tool suppliers, and silicon suppliers) as members from all over the world.

Employing novel surface micromachining techniques, a highly miniaturized, robust device has been fabricated. The accelerometer fulfills all requirements of state-of-the-art airbag systems. The present paper reports on the manufacturing and assembly process as well as the performance of the sensor. The capacitive sensing element consists of a moveable proof mass of polysilicon on a single crystalline silicon substrate. A lateral acceleration displaces the proof mass and a capacitive signal is generated at a comb electrode configuration. An external IC circuit provides the signal evaluation and conditioning in a closed loop mode, resulting in low temperature dependency of sensor characteristics and a wide frequency response. The sensor is fabricated by standard IC processing steps combined with additional surface micromachining techniques. A special deposition process in an epitaxial reactor allows the fabrication of moveable masses of more than 10 µm thickness.