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Due to the general requirements in the automotive industry to reduce the power consumption, fuel consumption rate and CO2 emission a new HID (High Intensity Discharge) bulb with only 25W is under development for front lighting systems. A first headlamp integrated in a hybrid vehicle is now launched as a first application in the market. The current regulation in ECE allows to get rid of the mandatory headlamp cleaning system and the automatic leveling requirement once the 25W HID bulb is applied. The reason for this is the objective luminous flux of the 25W HID bulb, which emits less than 2000 lm, a boundary defined in the regulation, where a headlamp cleaning and an automatic leveling is requested. That simplifies especially the integration in smaller vehicles and electric and hybrid vehicles. The paper describes the special design of the headlamp, the projector unit, the light performance, packaging advantages and future outlook of further applications in the near future.

Transient operation of turbocharged engines is mostly optimised in the light of quickness of response and the provision of the demanded torque. The time from demanded boosted torque to delivered torque above the maximum torque provided by the natural aspirated torque value is known as turbo-lag. This could reveal as an issue for small gasoline turbo-charged engines with a displacement of 1.0ltr or lower. These small types of engines are moving more and more in the focus for automobile applications. To provide the required power and torque, gasoline direct injection and turbo-charging are helpful in order to enable a reduction of fuel consumption by both de-throttled operation over a large area of operation and improved thermal efficiency among others achieved by maintaining an appropriate compression ratio.

Stratified operation of a gasoline engine is one of the most efficient technologies for fuel economy improvement. This operation requires detailed knowledge and governance of component tolerances (fuel injector and spark plug) in order to ensure robust and smooth engine operation without unacceptable torque fluctuations. The coefficient of variation (COV) is a metric in engine development and calibration for fluctuation of indicated mean effective pressure (IMEP), resp. torque (critical to quality), which means for the customer that the engine is running smoothly (critical to satisfaction). It denotes the relation of standard deviation of IMEP over 300 combustion cycles to the average IMEP over these cycles. COV performance must be below the specified levels, as a function of operating point, which can be translated into limit states at chosen engine speeds.

The design of internal combustion engines is more and more oriented toward sustainability, especially fuel economy. To reach this aim, several technologies have been developed, however, most significantly increase engine complexity and cost. An attractive way to achieve better fuel economy is the reduction of the engine's mechanical losses, which directly has positive influence on fuel economy. The strongest contributor to these losses is still the friction of the piston assembly. During the past decades, considerable progress in the reduction of piston and piston ring friction has been achieved. Beside the material and design of pistons and piston rings, the optimization of the liner's surface structure was always of interest, and a major role in this development was - and still is - played by surface coating technologies.

Legislation on vehicle emissions and the requirements for fuel efficiency are currently the key development driving factors in the automotive industry. Research activities to comply with these targets point to engine downsizing and new boosting technologies, which have adverse effects on the NVH performance, durability and component life. As a consequence of engine downsizing, substantial torsional oscillations are generated due to high combustion pressures. Meanwhile, to attenuate torsional vibrations, the manufacturers have implemented absorbers that are tuned to certain frequency ranges, including clutch dampers, Dual Mass Flywheel (DMF) and centrifugal pendulum dampers. These devices add mass/inertia to the system, potentially introducing negative effects on other vehicle attributes, such as weight, driving performance and gear shiftability.

A test procedure was developed to assess the deposit-forming tendencies of gasoline/ethanol fuel blends, ranging from 0 % to 100 % ethanol (E0 to E100). The test engine was a Ford 1.8l - 4 cylinder -16 valve -natural aspirated flex fuel engine, which is used in various vehicle models, such as the European Focus and C-MAX. The test cycle, a realistic engine speed/torque profile, based on an urban driving pattern, provided good differentiation between different gasoline/ethanol fuel blends as well as between additized and non-additized fuel blends. With unadditized E85 critical deposits were found in the intake system, on the intake valves, in the combustion chamber and on the injector tips. Well known deposit control additives (DCA) used in gasoline such as PIBA (polyisobutyleneamine) and PEA (polyetheramine) were examined in E85 for deposit control effectiveness of intake valves, injectors and combustion chambers.

Due to their CO2 reduction potential and their high knock resistance gaseous fuels present a promising alternative for modern highly boosted spark ignition engines. Especially the direct injection of LPG reveals significant advantages. Previous studies have already shown the highest thermodynamic potential for the LPG direct injection concept and its advantages in comparison to external mixture formation systems. In the performed research study a comparison of different LPG fuels in direct injection mode shows that LPG fuels have better auto-ignition behavior than gasoline. A correlation between auto-ignition behavior and the calculated motor octane number could not be found. However, a significantly higher correlation of R2 = 0.88 - 0.99 for CR13 could be seen when using the methane number. One major challenge in order to implement the LPG direct injection concept is to ensure the liquid state of the fuel under all engine operating conditions.

Development of propulsion control systems frequently involves large-scale transient simulations, e.g. Monte Carlo simulations or drive-cycle optimizations, which require fast dynamic plant models. Models of the air-path—for internal combustion engines or fuel cells—can exhibit stiff behavior, though, causing slow numerical simulations due to either using an implicit solver or sampling much faster than the bandwidth of interest to maintain stability. This paper proposes a method to reduce air-path model stiffness by adding an impedance in series with potentially stiff components, e.g. throttles, valves, compressors, and turbines, thereby allowing the use of a fast-explicit solver. An impedance, by electrical analogy, is a frequency-dependent resistance to flow, which is shaped to suppress the high-frequency dynamics causing air-path stiffness, while maintaining model accuracy in the bandwidth of interest.

Global automotive fuel economy and emissions pressures mean that 48 V hybridisation will become a significant presence in the passenger car market. The complexity of powertrain solutions is increasing in order to further improve fuel economy for hybrid vehicles and maintain robust emissions performance. However, this results in complex interactions between technologies which are difficult to identify through traditional development approaches, resulting in sub-optimal solutions for either vehicle attributes or cost. The results presented in this paper are from a simulation programme focussed on the optimisation of various advanced powertrain technologies on 48 V hybrid vehicle platforms. The technologies assessed include an electrically heated catalyst, an insulated turbocharger, an electric water pump and a thermal management module.

Diesel impulsiveness (so called Diesel knocking) present in the cabin of diesel vehicles is perceived as unpleasant because of its impulsive time structure. JD Power data clearly show the customers preference of vehicles with little Diesel knocking over those with severe knocking. Corresponding objective descriptors that reflect the customers' perception are introduced. The occurrence of such noise patterns is influenced by the combustion process itself as well as by all excited mechanical components within the power train. Further the transfer characteristics of the engine structure and various vehicle noise paths do contribute to a poor Diesel Sound Quality. It is essential that all these factors have to be considered in combination. This paper provides an overview about suitable methods and technologies, including Binaural Transfer Path Analysis and Synthesis. The potential of the approach is demonstrated by an example.

High combustion pressure in combination with high pressure gradient, as they e.g. can be evoked by high efficient combustion systems and e.g. by alternative fuels, acts as broadband excitation force which stimulates natural vibrations of piston, connecting rod and crankshaft during engine operation. Starting from the combustion chamber the assembly of piston, connecting rod and crankshaft and the main bearings represent the system of internal vibration transfer. To generate exact input and validation values for simulation models of structural dynamic and elasto-hydrodynamic coupled multi-body systems, experimental investigations are done. These are carried out on a 1.5-l inline four cylinder Euro 6 Diesel engine. The modal behaviour of the system was examined in detail in simulation and test as a basis for the investigations. In an anechoic test bench airborne and structure-borne noises and combustion pressure are measured to identify the engine´s vibrational behaviour.

The ability to switch off the internal combustion engine (ICE) during vehicle operation is a key functionality in hybrid powertrains to achieve low fuel economy. However, this can affect driveability, namely acceleration response when an ICE re-engagement due to a driver initiated torque demand is required. The ICE re-start as well as the speed and load synchronisation with the driveline and corresponding vehicle speed can lead to high response times. To avoid this issue, the operational range where the ICE can be switched off is often compromised, in turn sacrificing fuel economy. Based on a 48V off-axis P2 hybrid powertrain comprising a lay-shaft transmission we present an up-front simulation methodology that considers the relevant parameters of the ICE like air-path, turbocharger, friction, as well as the relevant mechanical and electrical parameters on the hybrid drive side, including a simplified multi-body approach to reflect the relevant vehicle and powertrain dynamics.

The application of a turbocharger, having an electric motor/generator on the rotor was studied focusing on the electric energy recuperation on a downsized gasoline internal combustion engine (turbocharged, direct injection) using 1D-calculation approaches. Using state-of-the art optimization techniques, the settings of the valve timing was optimized to cater for a targeted pre-turbine pressure and certain level of residual gases in the combustion chamber to avoid abnormal combustion events. Subsequently, a steady-state map of the potential of electric energy recuperation was performed while considering in parallel different efficiency maps of the potential generator and a certain waste-gate actuation strategy. Moreover, the results were taken as input to a WLTP cycle simulation in order to identify any synergies with regard to fuel economy.

The increase in efficiency is the focus of current engine development by adopting different technologies. One limiting factor for the rise of SI-engine efficiency is the onset of knock, which can be mitigated by improving the combustion process. HCCI/SACI represent sophisticated combustion techniques that investigate the employment of pre-chamber with lean combustion, but the effective use of them in a wide range of the engine map, by fulfilling at the same time the need of fast load control are still limiting their adoption for series engine. For these reasons, the technologies for improving the characteristics of a standard combustion process are still largely investigated. Among these, water injection, in combination with the Miller cycle, offers the possibility to increase the knock resistance, which in turn enables the rise of the engine geometric compression ratio.

The fuel consumption of modern passenger cars can be reduced by utilizing lightweight construction as well as by decreasing internal friction losses in the drive train. Modern engine blocks are partly made of cast iron or alumimum material whereas for the later hypo-eutectic AlSi-alloys dominate. Due to the low hardness, surfaces made of these alloys cannot be used as a friction partner for the piston rings. Cast iron liners are often inserted into the engine block to provide a wear-resistant surface for the piston rings. This work describes how cast iron liners can be replaced by thin, nanocrystalline iron based coatings in order to decrease friction losses as well as reduce the engine weight. The coatings were applied by thermal spraying with the Plasma Transferred Wire Arc internal diameter coating system.

The current political push for e-mobility marked a major decline in the R&D interest to internal combustion engine (ICE). Following this global trend, Ford is committed to going 100% electric by 2030 for passenger cars and 2035 for light commercial vehicles. At the same time, many researchers admit that, due to many objective factors, vehicles powered by ICE will remain in operation for decades to come. Development of alternative carbon-neutral fuels can bring a renaissance in the ICE development as practical limitations of electric-only approach get exposed. Since a significant part of energy losses in the ICE comes from friction, engine tribology has been an important research topic over the past two decades and a significant progress in improving the engine efficiency was achieved.