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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.

Tapping of one or more torques (ranges 10 Nm and 60 Nm) on the steering column for the purpose of servo control must satisfy high accuracy requirements on the one hand and high safety requirements on the other hand. A suggestion for developing a low-cost solution to this problem is described below: Strain gages optimally satisfy both these requirements: However, for cost reasons, these are not applied directly to the steering column but to a prefabricated, flat steel rod which is laser welded to the torque rod of the steering column. The measuring direction of the strain gages is under 45° to the steering column axis. The strain gages are either vacuum metallized onto the support rod as a thin film or laminated in a particularly low-cost way by means of a foil-type intermediate carrier.

The selective catalytic reduction (SCR) based on urea-water-solution is an effective technique to reduce nitrogen oxides (NOx) emitted from diesel engines. A 3D numerical computer model of the injection of urea-water-solution and their interaction with the exhaust gas flow and exhaust tubing is developed to evaluate different configurations during the development process of such a DeNOx-system. The model accounts for all relevant processes appearing from the injection point to the entrance of the SCR-catalyst: momentum interaction between gas phase and droplets evaporation and thermolysis of droplets hydrolysis of isocyanic acid in gas phase heat transfer between wall and droplets spray/wall-interaction two-component wall film including interaction with gas phase and exhaust tube The single modeling steps are verified with visualizations, patternator measurements, phase-doppler-anemometer results and temperature measurements.

The new aerial communication protocol “Controller Area Network” (CAN) efficiently supports distributed realtime control in automotive applications. In order to unload CPUs from high-speed message transfer, dedicated CAN hardware handles messages up to the communication object level. In multiplex wiring message rates are one to two orders of magnitude lower, allowing to implement the upper communication level more cost-effectively in software. This reduces CAN interface hardware to bitwise protocol handling only. It may be incorporated even into low-end microcontrollers without significantly increasing chip size. Thus the same CAN protocol supports the entire range of serial automotive communication, matching implementation costs to requirements at each performance level.

The continuing increase in the performance of restraint systems has led to a drastic increase in the number of actuator devices. The individual wiring of the igniters becomes more and more problematic through the accompanied large number of plug connections and cables. Along with demands for weight and volume reduction, there are requirements for EMI and short circuit protection to eliminate erroneous deployment and misuse. As a solution, a new multi-protocol dual wire bus system is described that has the capability to supply energy and address multiple peripheral output stages to simultaneously fire any combination of actuators.

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.

Current exhaust gas emission regulations can only be well adhered to through optimal interplay of combustion engine and exhaust gas after-treatment systems. Combining a modern diesel engine with several exhaust gas after-treatment components (DPF, catalytic converters) leads to extremely complex drive systems, with very complex and technically demanding control systems. Current engine ECUs (Electronic Control Unit) have hundreds of functions with thousands of parameters that can be adapted to keep the exhaust gas emissions within the given limits. Each of these functions has to be calibrated and tested in accordance with the rest of the ECU software. To date this task has been performed mostly on engine test benches or in Hardware-in-the-Loop (HiL) setups. In this paper, a Software-in-the-Loop (SiL) approach, consisting of an engine model and an exhaust gas treatment (EGT) model, coupled with software from a real diesel engine ECU, will be described in detail.

General Motors' 3.6L DOHC 4V V6 engine has been upgraded to provide substantial improvements in performance, fuel economy, and emissions for the 2008 model year Cadillac CTS and STS. The fundamental change was a switch from traditional manifold-port fuel injection (MPFI) to spark ignition direct injection (SIDI). Additional modifications include enhanced cylinder head and intake manifold air flow capacities, optimized camshaft profiles, and increased compression ratio. The SIDI fuel system presented the greatest opportunities for system development and optimization in order to maximize improvements in performance, fuel economy, and emissions. In particular, the injector flow rate, orifice geometry, and spray pattern were selected to provide the optimum balance of high power and torque, low fuel consumption, stable combustion, low smoke emissions, and robust tolerance to injector plugging.

This paper looks at the underlying fundamentals of diesel fuel system lubrication for the highly-loaded contacts found in fuel injection equipment like high-pressure pumps. These types of contacts are already occurring in modern systems and their severity is likely to increase in future applications due to the requirement for increased fuel pressure. The aim of the work was to characterise the tribological behavior of these contacts when lubricated with diesel fuel and diesel fuel treated with lubricity additives and model nitrogen and sulphur compounds of different chemical composition. It is essential to understand the role of diesel fuel and of lubricity additives to ensure that future, more severely-loaded systems, will be free of any wear problem in the field.

To achieve the future emissions regulations with low particulate and Nox levels, both the engine combustion system and the fuel injection equipment will have to be improved. For the fuel injection equipment, high injection pressure and variable injection timing as a function of engine speed, load, and temperature are of great importance. BOSCH is developing two different solutions: electronically controlled unit injector and single cylinder pump systems, high-pressure inline pumps with control sleeve and electronic control. This paper describes: the unit injector and its high-pressure solenoid valve the requirements for the mounting of the unit injector in the engine the low-pressure system the electronic control unit and the metering strategy

In mobile R-744 A/C units mechanical expansion devices (e.g. orifice tubes) or electronic valves (e.g. PWM-valves) can be used. Besides the costs, aspects like coefficient of performance (COP), cooling capacity or control behavior - especially for extreme conditions - influence the choice of the valve type. This paper will present a comparison between an ideal electronic valve and a two stage mechanical orifice tube under full load and part load conditions. The influence of the expansion valve on COP and cooling capacity in different ambient conditions can be sufficiently described with steady-state simulations. The simulation tools used for this work are based on Modelica/Dymola. The simulation results show that for European climate conditions the use of two-stage orifices might increase fuel consumption.

In order to reduce the spark-ignition engine exhaust-gas emission and fuel consumption, it is essential that the required air/fuel ratio is maintained under all operating conditions. An important contribution to this claim is delivered by the injection valve by metering the fuel precisely and producing fine atomization. In this report experimental methods to get specific measuring information and methods for optimizing flow in injection valves are described. Original valves as well as large-scale models were used for the investigations concerning the steady and unsteady-flow characteristics, and were equipped with a number of different sensors. Holograms of the short-time recording of the spray cone are generated and used for the quantification of the atomization quality when injecting into atmospheric pressure and into vacuum, thus complying with the conditions encountered in the engine intake-manifold.

Fully Variable Valve Actuation (FVVA) systems enable to employ a wide range of combustion strategies by providing the actuation of a gas exchange valve at an arbitrary point in time, with variable lift and adjustable ramps for opening and closing. Making such a system ready for the market requires appropriate fault-diagnostic functionality. Here, we focus on diagnosis possibilities by using air intake system sensors such as Manifold Absolute Pressure (MAP) sensors. Results obtained on a 4-cylinder test bench engine are presented for the early intake opening strategy under different loads, and at medium range rotational speeds on steady-state conditions. It is shown that detection and identification of the different critical faults on each actuator is possible by using a Fourier series signal model of the MAP sensor.

The particulate emissions can be reduced by increasing injection pressure. The NOx-emission can be lowered to the required amount with a retarded injection-begin. These measures raise fuel consumption by approximately 8-10 %. To avoid blue smoke from the cold engine, it is advantageous that the fuel injection is advanced during the warm-up period. These statements apply for injection systems with unit injectors as well as for pump-line-nozzle-systems. In this paper, the pump-line-nozzle-system will be described. With this system, injection pressures of 1200 to 1400 bar at the injection nozzle are reached. The injection-begin can be changed with a control-sleeve in-line pump. The injection-begin and fuel quantity can be flexibly and accurately adjusted by means of an electronic governor.

Historically, whenever the automotive solutions’ state of art reaches a saturation level, the integration of new verticals of technology has always raised new opportunities to innovate, enhance and optimize automotive solutions. The predictive powertrain solutions using connectivity elements (e.g., navigation unit, e-Horizon or cloud-based services) are one of such areas of huge interest in automotive industry. The prior knowledge of trip destination and its route characteristics has potential to make prediction of powertrain modes or events in certain order and therefore it can add value in various application areas such as optimized energy management, lower fuel consumption, superior safety and comfort, etc.

Within the Robert Bosch Diesel Injection Pump Program, the MW and P pumps have a fundamental significance concerning medium-duty and heavy- duty engines. These engines have developed considerably in the last years with regard to combustion efficiency and emission reduction. In order to reach these new targets, specific developments of the pump were necessary to realize injection pressure of 900 bar and 1200 bar for the MW and P pumps, respectively. A further development emphasis of the past years was the development of a robust electronic governor concept to take advantage of this new technology. The topics of the paper are: Further development of the pump drivetrain and housing to cope with the difficulties inherent in producing 1000 bar. Development of constant-pressure valves. Preparation of the electronic governor concept for commercial vehicles. Development results of the electro-magnetic and electro-hydraulic actuators.

Time Triggered CAN (TTCAN) is an extension of the well-known CAN protocol, introducing to CAN networks time triggered communication and a system wide global network time with high precision. Time Triggered CAN has been accepted as international standard ISOCD11898-4. The time triggered communication is built upon the unchanged standard CAN protocol. This allows a software implementation of the time triggered function of TTCAN, based on existing CAN ICs. The high precision global time however requires a hardware implementation. A hardware implementation also offers additional functions like time mark interrupts, a stopwatch, and a synchronization to external events, all independent of software latency times. The TTCAN testchip (TTCAN_TC) is a standalone TTCAN controller and has been produced as a solution to the hen/egg problem of hardware availability versus tool support and research.

In order to optimize the inner flow of the regenerative pump used in gasoline injection systems, we carry out experimental and numerical flow investigations. A qualitative analysis of spatial flow phenomena in selected regions of the pump is presented by employing the laser light sheet technique. Therefore, a tenfold enlarged water model is built up, where dynamic similarity with the original flow is achieved. The results of the flow analysis have led to improved geometries which are compared with the original design by measured pump characteristic curves. Furthermore, three-dimensional simulations of the fully developed turbulent flow using a finite-element method are presented. The flow with respect to the rotating impeller is calculated by solving the Reynolds equations in connection with the k-ε-turbulence model.

Acoustics and vibrations are amongst the foremost indicators in perceiving the quality of drive units. Analyzing these factors is vital for improve the performances of electro-mechanical systems. This paper deals with the study of vibro-acoustic behavior concerning the drivetrain components using system modeling and Finite Element calculations. A generic simulation methodology within system modeling is proposed enabling the vibro-acoustic simulation of electro-mechanical drivetrains. Excitations for these systems mostly arise from the electric motor and mechanical gears. The paper initially depicts the system model for gear whining considering the associated nonlinearities of the mesh. The results obtained from the gear mesh submodel, together with the excitations resulting from the motor, aid in the comprehension of the forces at the bearings and of the vibrations at the housings.

In new exhaust system specifications such as single cylinder balancing, closed coupled catalyst systems, sensor locations close to the engine, turbo applications, fast light off situations and diesel engine applications the dynamic behavior of the lambda sensor becomes more important. This demands a detailed knowledge and modeling of the relevant parameters. In former analysis of exhaust gas sensors the main focus has been the electrochemical processes in the sensor. The influence of flow structure and protection tubes had lower priority. In this paper we present the numerical and experimental analysis of cold air flowing in a pipe including mounted exhaust sensors. Two double-protection tubes from the Robert Bosch GmbH have been examined named (a) and (b). The predicted results have been compared with values measured with Laser Doppler Anemometry (LDA). The flow pattern in the protection tube type (a) depends on the geometric configuration of the sensor element and the tubes.