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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.

The automotive industry continues to develop new powertrain technologies aimed at reducing overall vehicle level fuel consumption. The ongoing trends of “downsizing” and “down speeding” have led to the development of turbocharged engines with low displacement and high torque density. In order to meet the launch response requirements with these engines as well as fuel economy needs, transmissions with large ratio spreads will need to be developed. Due to the lack of torque amplification from the torque converter, the next generation of dual clutch transmissions (DCT) will need to have larger launch ratios and ratio spreads than currently available in production today. This paper discusses the development of a new family of DCT (called “xDCT”) for use in front wheel drive vehicles, aimed at meeting some of these challenges. The xDCT family features two innovative concepts, the idea of “gear generation” and “supported shifts”.

The interest in electric propulsion of vehicles has increased in recent years and is being discussed extensively by experts as well as the public. Up to now the driving range and the utilization of pure electric vehicles are still limited in comparison to conventional vehicles due to the limited capacity and the long charging times of today's batteries. This is a challenge to customer acceptance of a pure electric vehicle, even for a city car application. A Range Extender concept could achieve the desired customer acceptance, but should not impact the “electric driving” experience, and should not cause further significant increases in the manufacturing and purchasing cost. The V2 engine concept presented in this paper is particularly suited to a low cost, modular vehicle concept. Advantages regarding packaging can be realized with the use of two generators in combination with the V2 engine.

A new approach is presented to modelling wall heat transfer in the exhaust port and manifold within 1D gas exchange simulation to ensure a precise calculation of thermal exhaust enthalpy. One of the principal characteristics of this approach is the partition of the exhaust process in a blow-down and a push-out phase. In addition to the split in two phases, the exhaust system is divided into several sections to consider changes in heat transfer characteristics downstream the exhaust valves. Principally, the convective heat transfer is described by the characteristic numbers of Nusselt, Reynolds and Prandtl. However, the phase individual correlation coefficients are derived from 3D CFD investigations of the flow in the exhaust system combined with Low-Re turbulence modelling. Furthermore, heat losses on the valve and the seat ring surfaces are considered by an empirical model approach.

This work is a continuation of earlier results presented by the authors. In the current investigations the biofuels hydrogenated vegetable oil (HVO) and 1-octanol are investigated as pure components and compared to EN 590 Diesel. In a final step both biofuels are blended together in an appropriate ratio to tailor the fuels properties in order to obtain an optimal fuel for a clean combustion. The results of pure HVO indicate a significant reduction in CO-, HC- and combustion noise emissions at constant NOX levels. With regard to soot emissions, at higher part loads, the aromatic free, paraffinic composition of HVO showed a significant reduction compared to EN 590 petroleum Diesel fuel. But at lower loads the high cetane number leads to shorter ignition delays and therefore, ignition under richer conditions.

In September 2013 the Jaguar XF 2.2l ECO sport brake and saloon were introduced to the European market. They are the first Jaguar vehicles to realize CO2 emissions below 130 g/km. To achieve these significantly reduced fuel consumption values with an existing 2.2l I4 Diesel engine architecture, selected air path and fuel path components were optimized for increased engine efficiency. Tailored hardware selection and streamlined development were only enabled by the consequent utilisation of the most advanced CAE tools throughout the design phase but also during the complete vehicle application process.

This study investigated dual-fuel operation with a light duty Diesel engine over a wide engine load range. Ethanol was hereby injected into the intake duct, while Diesel was injected directly into the cylinder. At low loads, high ethanol shares are critical in terms of combustion stability and emissions of unburnt hydrocarbons. As the load increases, the rates of heat release become problematic with regard to noise and mechanical stress. At higher loads, an advanced injection of Diesel was found to be beneficial in terms of combustion noise and emissions. For all tests, engine-out NOx emissions were kept within the EU-6.1 limit.

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.

With the increasing popularity of seamless gear changing and smooth driving experience along with the need for high fuel efficiency, transmission system development has rapidly increased in complexity. So too has transmission control software while quality requirements are high and time-to-market is short. As a result, extensive testing and documentation along with quick and efficient development methods are required. FEV responds to these challenges by developing and integrating a transmission software product line with an automated verification and validation process according to the concept of Continuous Integration (CI). Hence, the following paper outlines a software architecture called “PERSIST” where complexity is reduced by a modular architecture approach. Additionally, modularity enables testability and tracking of quality defects to their root cause.

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.

The Bharat Stage VI (BS-VI) emission legislation will come into force in 2020, posing a major engineering challenge in terms of system complexity, reliability, cost and development time. Solutions for the EURO VI on-road legislation in Europe, from which the BS-VI limits are derived, have been developed and have already been implemented. To a certain level these European solutions can be transferred to the Indian market. However, several market-specific challenges are yet to be defined and addressed. In addition, a very strict timeline has to be considered for application of advanced technologies and processes during the product development. In this paper, the emission roadmap will be introduced in the beginning, followed by a discussion of potential technology solutions on the engine itself as well as on the exhaust aftertreatment side. This includes boosting and fuel injection technologies as well as different exhaust gas recirculation methods.

The Bharat Stage (CEV/Tractor) IV & V emission legislations will come into force in Oct 2020 & Apr 2024 respectively, posing a major engineering challenge in terms of system complexity, reliability, costs and development time. Solutions for the EU Stage-V NRMM legislation in Europe, from which the BS-V limits are derived, have been developed and are ready for implementation. To a certain extent these European solutions can be transferred to the Indian market. However, certain market-specific challenges are yet to be defined and addressed. In addition, a challenging timeline has to be considered for application of advanced technologies and processes during the product development. In this presentation, the emission roadmap will be introduced in the beginning, followed by a discussion of potential technology solutions on the engine itself as well as on the after treatment components.

Legislative restrictions on the currently limited exhaust gas components and the future CO2 emissions limits have led to intensive research in the field of alternative fuels and innovative combustion approaches. Increased homogeneity of air-fuel mixture through advanced injection is one combustion approach, which potentially reduces engine-out nitrogen oxide and particulate emissions, with good fuel consumption in certain load ranges. Ignition characteristics under homogenous combustion conditions differ from those under heterogeneous conditions. Among other reasons, this is due to the increased role of low temperature chemistry with increasing homogeneity. The ignition behaviour of diesel fuels is characterised by the Cetane number (CN), which is, however, determined at significant higher temperatures than those prevalent during ignition under homogenous combustion. As a result, its relevance as a fuel characteristic number requires evaluation.

Despite the trend in increased prosperity, the Indian automotive market, which is traditionally dominated by highly cost-oriented producion, is very sensitive to the price of fuels and vehicles. Due to these very specific market demands, the U-LCV (ultra-light commercial vehicle) segment with single cylinder natural aspirated Diesel engines (typical sub 650 cc displacement) is gaining immense popularity in the recent years. By moving to 2016, with the announcement of leapfrogging directly to Bharat Stage VI (BS VI) emission legislation in India, and in addition to the mandatory application of Diesel particle filters (DPF), there will be a need to implement effective NOx aftertreament systems. Due to the very low power-to-weight ratio of these particular applications, the engine operation takes place under full load conditions in a significant portion of the test cycle.

Tighter emission limits are discussed and established around the world to improve quality of the air we breathe. In order to control global warming, authorities ask for lower CO2 emissions from combustion engines. Lots of efforts are done to reduce engine out emissions and/or reduce remaining by suitable after treatment systems. Watlow, among others, a manufacturer of high accurate, active temperature sensor ExactSense™, wanted to understand if temperature sensor accuracy can have an influence on fuel consumption (FC). For this purpose a numerical approach was chosen where several non-road driving cycles (NRTCs) were simulated with the data base of a typical Stage IV heavy duty diesel engine. The engine is equipped with an exhaust gas after treatment system consisting of a DOC, CDPF and an SCR. In this work scope, the investigations shall be restricted to the FC benefits obtained in the active and passive DPF regeneration.

The residue and waste streams of existing industry offer feasible and sustainable raw materials for biofuel production. All kind of biomass contains carbon and hydrogen which can be turned into liquid form with suitable processes. Using hydrotreatment or Biomass-to-Liquid technologies (BTL) the liquid oil can be further converted into transportation biofuels. Hydrotreatment technology can be used to convert bio-oils and fats in to high quality diesel fuels that have superior fuel properties (e.g. low aromatic content and high cetane number) compared to regular diesel fuel and first generation ester-type diesel fuel. UPM has developed a new innovative technology based on hydrotreatment that can be used to convert Crude Tall Oil (CTO) into high quality renewable diesel fuel. This study concentrated on determining the functionality and possible effects of CTO based renewable diesel as a blending component on engine emissions and engine performance.

Model-based control strategies along with an adapted calibration process become more important in the overall vehicle development process. The main drivers for this development trend are increasing numbers of vehicle variants and more complex engine hardware, which is required to fulfill the more and more stringent emission legislation and fuel consumption norms. Upcoming fundamental changes in the homologation process with EU 6c, covering an extended range of different operational and ambient conditions, are suspected to intensify this trend. One main reason for the increased calibration effort is the use of various complex aftertreatment technologies amongst different vehicle applications, requiring numerous combustion modes. The different combustion modes range from heating strategies for active Diesel Particulate Filter (DPF) regeneration or early SCR light-off and rich combustion modes to purge the NOx storage catalyst (NSC) up to partially premixed combustion modes.

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.