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Innovative solutions for reducing particulate emissions will be necessary in order to comply with the even more stringent exhaust-gas standards of the future. The potential of a diesel nozzle with variable orifice geometry has long been common knowledge in the area of engine construction. But up to now, a fully functional solution of such a nozzle has not appeared which operates with a reduced orifice at low engine speeds and/or low loads. Here with regard to target costing, the requirements implicit in function and manufacture must also be taken into account. Using calculations on nozzle interior flow and injection-spray investigations, it will be shown which nozzle geometries best fulfill the various requirements. In order to achieve low levels of particulate emission in an engine with a combustion chamber designed for optimum use of a hole-type nozzle, the injection-spray direction and its geometry must to a large extent correspond to those of a hole-type nozzle.

The manufacturers of passenger cars increasingly assign development and production of complete subsystems to the supplying industry. A brake system supplier has to give predictions about system quality and performance long time before the first prototypical system is built or even before the supplier gets the order for system development. Nowadays, the usage of computer-aided system design and simulation is essential for that task. This article presents a tool designed to support the development process. A special focus will be on how to define quality. A formal definition of quality is provided, illustrated and motivated by two examples.

This study reports on laser-based diagnostics to temporally track the evolution of liquid and gaseous fuel in the cylinder of a direct injection production type Diesel engine. A two-dimensional Mie scattering technique is used to record the liquid phase and planar laser-induced fluorescence of Diesel is used to track both liquid and vaporised fuel. LIF-Signal is visible in liquid and gas phase, Mie scattering occurs only in zones where fuel droplets are present. Distinction between liquid and gaseous phase becomes therefore possible by comparing LIF- and Mie-Signals. Although the information is qualitative in nature, trends of spray evolution are accessible. Within this study a parametric variation of injection pressure, in-cylinder conditions such as gas temperature and pressure as well as piston geometry are discussed. Observations are used to identify the most sensitive parameters and to qualitatively describe the temporal evolution of the spray for real engine conditions.

Novel Combustion technologies and strategies show high potential in reducing the fuel consumption of gasoline spark ignition (SI) engines. In this paper, a comparison between various gasoline combustion concepts at two representative engine operating points is shown. Advantages of the combustion concepts are analyzed using thermodynamic split of losses method. In this paper, a tool for thermodynamic assessment (Split of Losses) of conventional and new operating strategies of SI engine and its derivatives is used. Technologies, like variable valve actuation and/or gasoline direct injection, allow new strategies to run the SI engine unthrottled with early inlet valve closing (SI-VVA) combined with high EGR, charge stratification (SI-STRAT) and controlled auto ignition (CAI), also known as gasoline homogeneous charge compression ignition (HCCI). These diverse combustion concepts show thermodynamic gains that stem from several, often different sources.

The range of Robert Bosch in-line pumps is designed for engines with cylinder outputs of up to 200 kW. Within this family of pumps the MW pump is used in small IDI engines and medium-sized DI engines with cylinder outputs in the region of 30 kW. More stringent exhaust emission legislation and the need to ensure optimum fuel economy call for efficient fuel-injection systems for diesel engines. In both of its designs the new MW pump meets these more exacting requirements and forms the contribution of Robert Bosch GmbH toward developing advanced diesel engines.

The hydro grinding process can be used for valve covered orifice (VCO) nozzle production. A comprehensive numerical and experimental investigation was performed to determine the influence of hydro grinding (HG) at VCO nozzles on the mixture preparation in pressure charged high speed direct injection diesel engines. Samples of five hole VCO nozzles with defined grades of HG and different sprayhole diameters were selected to ensure a constant mass flow at a fixed feeding pressure for comparable engine tests. The simulation of the internal flow shows a more symmetrical velocity profile indicating less shear flow and lower turbulence intensities at the orifice with increased HG grade. From these results an enhanced atomization at further penetration depth and reduced atomization close to the nozzle could be expected. This was confirmed by measuring the spray momentum distribution and spray tip speed by mechanical and optical probes in high pressure vessels.

A previous study by the authors has shown an efficiency benefit of up to Δηi = 10 % for stratified operation of a high pressure natural gas direct injection (DI) spark ignition (SI) engine compared to the homogeneous stoichiometric operation with port fuel injection (PFI). While best efficiencies appeared at extremely lean operation at λ = 3.2, minimum HC emissions were found at λ = 2. The increasing HC emissions and narrow ignition time frames in the extremely lean stratified operation have given the need for a detailed analysis. To further investigate the mixture formation and flame propagation und these conditions, an optically accessible single-cylinder engine was used. The mixture formation and the flame luminosity have been investigated in two perpendicular planes inside the combustion chamber.

The tightening of Heavy Duty Diesel (HDD) emissions legislation throughout the world is leading to the development of emission control devices to enable HDD engines to meet the new standards. NOx and Particulate Matter (PM) are the key pollutants which these emission control systems need to address. Diesel Particulate Filters (DPFs) are already in use in significant numbers to control PM emissions from HDD vehicles, and Selective Catalytic Reduction (SCR) is a very promising technology to control NOx emissions. This paper describes the development and performance of the Compact SCR-Trap system - a pollution control device comprising a DPF-based system (the Continuously Regenerating Trap system) upstream of an SCR system. The system has been designed to be as easy to package as possible, by minimising the total volume of the system and by incorporating the SCR catalysts on annular substrates placed around the outside of the DPF-based system.

The reduction of nitrous oxides in the exhaust gases of internal combustion engines using a urea water solution is gaining more and more importance. While maintaining the future exhaust gas emission regulations, like the Euro 6 for passenger cars and the Euro 5 for commercial vehicles, urea dosing allows the engine management to be modified to improve fuel economy as well. The system manufacturer Robert Bosch has started early to develop the necessary dosing systems for the urea water solution. More than 300.000 Units have been delivered in 2007 for heavy duty applications. Typical dosing quantities for those systems are in the range of 0.01 l/h for passenger car systems and up to 10 l/h for commercial vehicles. During the first years of development and application of urea dosing systems, instantaneous flow measuring devices were used, which were not operating fully satisfactory.

In the last decades the development of Diesel engines has made substantial progress. New, powerful and scalable injection systems have been introduced. In consequence Diesel systems are continuously gaining market share in many places of the world. Advanced direct injection engines with systems like the electronically controlled distributer pump, the unit injection system and of course the common rail system are replacing the chamber engines in all automotive applications. This is all unthinkable without the electronic management of these injection systems by means of Electronic Diesel Control units (EDC). The following presentation describes the status and some future trend of technology of EDCs with particular emphasis on functional and on software development. It also outlines the challenge of global automotive industry that requires global development and application services from its tier 1 suppliers.

The stricter worldwide emission legislation and growing demands for lower fuel consumption and CO2-emission require for significant efforts to improve combustion efficiency while satisfying the emission quality demands. Ethanol fuel combined with boosting on direct injection gasoline engines provides a particularly promising and, at the same time, a challenging approach. Brazil is one of the main Ethanol fuel markets with its E24 and E100 fuel availability, which covers a large volume of the national needs. Additionally, worldwide Ethanol availability is becoming more and more important, e.g., in North America and Europe. Considering the future flex-fuel engine market with growing potentials identified on downsized spark ignition engines, it becomes necessary to investigate the synergies and challenges of Ethanol boosted operation. Main topic of the present work focuses on the operation of Ethanol blends up to E100 at high loads up to 30 bar imep.

Fuel economy of two-wheelers is an important factor influencing the purchasing psychology of the consumer within the emerging markets. Additionally, air pollution being a major environmental topic, there is a rising concern about vehicle emissions, especially in the big cities and their metropolitan areas. Potentially, the relatively expensive engine management systems are providing more features and value in comparison to the carburettor counterpart. The combustion system analysis is carried out on a 125 cm3 motorcycle engine and the subsequent numerical simulation comparing the carburettor and the Electronic (Port) Fuel Injection which provides a basis to establish the fuel consumption benefit for the electronic injection systems [1].

Two-dimensional Mie and LIEF techniques were applied to investigate the spray formation of a high pressure gasoline swirl injector in a constant volume chamber. The results obtained provide information on the propagation of liquid fuel and fuel vapor for different fuel pressures and ambient conditions. Spray parameters like tip penetration, cone angles and two new defined parameters describing the radial fuel distribution were used to quantify the fuel distributions measured. Simultaneous detection of liquid and vapor fuel was applied to study the influence of ambient temperature, injector temperature and ambient pressure on the evaporating spray.

This paper will describe the procedures that will enhance the possibilities of qualitative evaluation of headlamp light distributions. A basis will be the description of a light distribution coming only from reflector geometries, i.e. headlamps with clear outer lens design. Further steps of evaluation, as visualization and homogeneity analysis become more and more important for a headlamp evaluation. The recently developed tools can support both the headlamp manufacturer and the car manufacturer in finding a common understanding in headlamp performance of a projected car at a very early stage of development.

The Side View Assist is the World’s first rider assistance system for two-wheelers. This is a Blind Spot Warning system, which uses four ultrasonic sensors to monitor the surrounding of the rider. Whenever there is a vehicle (i.e. a car, truck, or another motorbike) in the rider’s blind spot, the technology warns the rider with an optical signal close to the mirror. This will allow the rider to avoid a collision when changing lanes. In the current vehicle application, Side View Assist is active at speeds ranging from 25 to 80 kilometers per hour and supports riders whenever the difference in relative speed to other road users is small. The system helps to improve safety especially in cities, where heavy traffic makes it necessary to change lanes more often. Originally such systems have been developed for cars and different system solutions for cars have been in serial production for several years. The challenge was to adapt these systems so they would work for two-wheelers as well.

A new high-performance interchip interface, called Serial WireRing, is introduced. It combines technically mature and established methods, whereby Serial WireRing provides a simple, robust and very inexpensive solution to replace the Serial Peripheral Interface (SPI). Serial WireRing uses a daisy chain ring topology, realized by unidirectional point-to-point connections from device to device. Serial WireRing is realized by a simple “wire ring” with CMOS, LVDS, optical or any other suitable signaling, even mixed. Therefore it has a very low pin count. In order to minimize the latency each slave transmits the data that it receives with 1 bit delay only. In order to avoid clock/data skew, the serial data and clock are merged into one bitstream. A corresponding clock is extracted at each receiver by a clock and data recovery circuit, driven by a simple internal oscillator.

This paper describes the architecture and the implementation of a software for the communication between networked in-vehicle ECUs. The communication software is based upon a real-time multitasking operating system. The operating system and the communication software form an application-independent platform for the implementation of distributed ECU software. The software architecture consists of several communication layers and a station management module. The communication layers provide network driver, data transfer services and an application interface that is independent of the used network protocol. The station management module is responsible for configuration and initialization of the communication controller, error detection during operation and error handling. The modula r structure of the architecture supports the simple adaptation of the software to different bus systems and communication controllers.

Increasing injection pressures together with Diesel fuel lubricated Common Rail pumps replacing oil lubricated systems demand a more sophisticated investigation of robustness and durability against particle contamination of fuel. The established way of requiring filtration efficiency levels per lab standard is not significant enough if we look at variable factors like vibration of the fuel filter and viscosity of the fuel. Because these and other factors tremendously influence filtration efficiency, future Diesel FIE cleanliness requirements will need to define an allowable contamination limit downstream of the filter. More precisely, this is not a scalar limit but a contamination collective that considers the varying vehicle filtration and operating environment. This paper describes a procedure for defining allowable contamination limits of the FIE components. The procedure includes sensitivity, robustness and “key life” tests.

The antiskid systems which have been on the market for some time are characterized by the fact that they are separate from the brake power-assist unit and are positioned between the master cylinder and the wheel brakes (separate configuration). At present, integrated antiskid systems are also being prepared for launching on the market. In these systems the hydraulic brake power-assist unit performs the functions of brake boosting and partly also of ABS pressure modulation. The principles of ABS pressure modulation in separate and integrated antiskid systems are compared and questions concerning safety are discussed. With the separate ABS (plunger system, return system) the brake circuits are closed, i.e. when braking and also during ABS operation the volume of brake fluid between the master cylinders and the wheel brake cylinders is closed and separated from the energy supply of the hydraulic brake power-assist unit.

A major trend in modern vehicle control is the increase of complexity and interaction of formerly autonomous systems. In order to manage the resulting network of more and more integrated (sub)systems Bosch has developed an open architecture called CARTRONIC for structuring the entire vehicle control system. Structuring the system in functionally independent components improves modular software development and allows the integration of new elements such as integrated starter/generator and the implementation of advanced control concepts as drive train management. This approach leads to an open structure on a high level for the design of advanced vehicle control systems. The paper describes the integration of the spark-ignition (SI) engine management system (EMS) into a CARTRONIC conform vehicle coordination requiring a new standard interface between the vehicle coordination and the EMS level.