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The tighter exhaust emissions standards introduced by governments for light duty vehicles are challenging car manufactures to meet at the same time legal emission limits and fuel efficiency improvements, still providing excellent fun to drive characteristics. The Hybrid and Diesel propulsion systems are two important players on that competition. In this scenario, the 48 V hybridization has the potential to become a cost-effective solution compared to High Voltage systems, outlining a new way to approach the well-known trade-off between CO2 and NOx in Diesels. Aim of this study has been to investigate the benefits offered by a P0 48 V Hybrid system when coupled with a 1.6 L Diesel engine in a 7-seat multi-purpose vehicle.

A series of designed experiments (DOE) was used to optimize the seat and orifice designs in a multi stream gasoline direct injector. The goal of the experiments was to minimize the effects of fuel deposits on the injector performance. Two different engines were used in the test campaign. One engine, a centrally injected turbocharged 1.6L four cylinder, was used to run a three factor full factorial DOE that tested the effects of SAC volume design, tip design and combustion seal position. Another, a centrally injected turbocharged 3.0L six cylinder, was used to run a three factor full factorial and a four factor half factorial DOE. The three factors in the full factorial were orifice hole divergence, orifice hole surface finish and the use of an inert amorphous silicon coating. A fourth factor, hydro erosive grinding of the orifice holes, was added to facilitate the calculation of a four factor half factorial DOE with only four additional engine tests.

The combustion engine will be the dominant drive for motor vehicles despite all the advances in the electrification of the drive train, for many years. The greater are the challenges for the automotive industry, especially in fuel consumption (CO2) and the environmental impacts of other emissions. From the fuel supply to the engine, up to the exhaust after treatment, new or improved functions are needed, which are integrated into increasingly powerful control electronics. This modern electronic engine management and powertrain controller will remain key components in the vehicle. As most of the micro controllers for future applications will be MultiCores, this paper gives an overview on how PowerSAR® supports this kind of architectures. It shows the concepts applied in the basic software area as well as for the applicative software. Further it will show the impact on the development process as well as the integration support for software delivered by the OEM.

It is well know that the internal flow field and nozzle geometry affected the spray behavior, but without high-speed microscopic visualization, it is difficult to characterize the spray structure in details. Single-hole diesel injectors have been used in fundamental spray research, while most direct-injection engines use multi-hole nozzle to tailor to the combustion chamber geometry. Recent engine trends also use smaller orifice and higher injection pressure. This paper discussed the quasi-steady near-nozzle diesel spray structures of an axisymmetric single-hole nozzle and a symmetric two-hole nozzle configuration, with a nominal nozzle size of 130 μm, and an attempt to correlate the observed structure to the internal flow structure using computational fluid dynamic (CFD) simulation. The test conditions include variation of injection pressure from 30 to 100 MPa, using both diesel and biodiesel fuels, under atmospheric condition.

In the past few years the gasoline direct injection (GDI) downsizing approach was the dominating gasoline engine technology used to reduce CO2 emission and to guarantee excellent transient performance. Forecasts for the next several years indicate that the worldwide market share of GDI engines will grow further. By 2022 it is expected that the gasoline DI engine will be the most popular combustion engine for passenger car application. However in the future the gasoline engine will have to comply with more stringent emission and CO2 standards. The European legislation demands a fleet average CO2 emission of 95g/km latest by 2021. Therefore, CO2 emission improvement, without compromising driveability, is the major goal of powertrain development. The perspective of more stringent CO2 and emission legislation in highly loaded drive cycle necessitates major development efforts.

These last years, much of researches were carried out to find the appropriate substitution fuel to the fossil fuels. The use of biofuel prepared from non-edible vegetable oils are becoming a promising source to produce a fuel for diesel engine, commonly referred to as “biodiesel”. Considering the high oil extraction yield (around 40%) and the great quantity of pistacia lentiscus (PL) trees available in arid and semi-arid areas of Mediterranean countries, it is selected in the present work to study the biodiesel prepared from PL oil. PL biodiesel is obtained by converting PL seed oil with a single-step homogenous alkali catalyzed transesterification process. PL biodiesel characterization, according to the standard methods, shows that the physicochemical properties are comparable to those of conventional diesel fuel. In a second part, a single cylinder air-cooled, DI diesel engine is used to test PL biodiesel at 1500 rpm under various engine load conditions.

Knock is a major technological constriction of natural gas spark ignition engines. Nowadays, it is widely accepted that knock is due to auto-ignition in the end gas region. Knock can occur for different reasons, which could be related to the engine itself (design and settings) or to the gas composition (or the gas quality). In a previous study the effect of engine settings on knock in a C.F.R. SI engine fuelled by pure methane was established by using a knock indicator, based on the evaluation of the energy of end gases. The paper deals with knock limit prediction from natural gas quality in a C.F.R. engine. A 2-zone thermodynamic model was developed in order to predict knocking conditions by evaluating a knock indicator. The model relies on some standard assumptions. Ignition delay was expressed as a function of engine settings, and a physical correlation for the heat release rate model was used.

Numerical simulation is a useful and a cost-effective tool for engine cycle prediction. In the present study, a dual Wiebe function is used to approximate the heat release rate in a DI, naturally aspirated diesel engine fuelled with eucalyptus biodiesel/diesel fuel blends and operated at various engine loads. This correlation is fitted to the experimental heat release rate at various operating conditions (fuel nature and engine load) using a least squares regression to find the unknown parameters. The main objective of this study is to propose a model to predict the Wiebe function parameters for more general operating conditions, not only those experimentally tested. For this purpose, an artificial neural network (ANN) is developed on the basis of the experimental data. Engine load and eucalyptus biodiesel/diesel fuel blend are the input layer, while the six parameters of the dual Wiebe function are the output layer.

During recent years, all major North American and European commercial vehicle OEMs have introduced predictive functionalities based on an electronic horizon for their on-highway fleets. This is a system concept that lets vehicles know what is happening on the road ahead and allows them to react to that information without driver involvement. When an electronic horizon is used in heavy-duty trucks, a significant reduction in fuel consumption is possible as a key application. This is achieved by optimizing the algorithms in the engine control unit, the transmission control device or other control units in the vehicle. There is a clear business case for the vehicle owners. In this paper we review the long development from early navigation technologies to an in-vehicle sensor, called an electronic horizon. We present an overview of different architectures from several perspectives as well as multiple use cases for commercial vehicles.

Beside the fuel consumption reduction the emission reduction is one of the main development objectives. The oncoming increasingly stringent emission limits demand improvements to the emission level especially in the cold start and engine warm-up phase when the catalyst is still inactivate. In this phase it is necessary to produce raw emissions on a very low level and to reach the catalyst light-off temperature as fast as possible using a suitable injection strategy. In this paper the potentials and risks of injection strategies for efficient catalyst heating (lean warm-up without secondary-air pump) with piezo and solenoid GDI combustion systems, in side and central mounting position, are introduced. The main emphasis is to obtain low HC emissions and high exhaust heat flow with acceptable engine smoothness by deriving suitable tuning parameters. During the investigations the various degrees of freedom of the applied GDI Engine were used in the best possible way.

The crude oil depletion, as well as aspects related to environmental pollution and global warming has caused researchers to seek alternative fuels. Biogas is one of the most attractive available fuels. It is of great interest both economically and ecologically. However, it faces problems that may compromise its industrial use. The dual-fuel engines have been investigated as a technique for the recovery of these gases and finding solutions to these problems. In the present work, performance and emissions of a direct injection diesel engine were first evaluated in conventional mode and dual fuel mode. The effect of biogas composition, based on methane content, is then examined. Also, dual fuel operation with regard to knock is investigated. The results show that, up to 95% of engine full load, the brake thermal efficiency (BTE) is lower in dual fuel mode. In terms of the specific consumption, although at high load the gap is much less, it is more significant in case of dual fuel mode.

Steel-made components of modern fuel injection systems are designed for pressure amplitudes of ≥300 bar (gasoline engines) and 2200 bar (diesel engines), respectively. In order to evaluate the risk of field failure, for example, for a service life of 300 000 miles, Wöhler pulsation tests are conducted at very high-pressure levels far beyond the service pressure. In a standard procedure, the results of these high-cycle fatigue (HCF) tests with an ultimate number of cycles of 5∙106 are extrapolated down to real-life load amplitudes, assuming that there is a unique function for the dependency of failure probability PA on pressure amplitude Δp, regardless of the different failure mechanisms and crack initiation sites, like surface imperfections, internal defects, etc.

The aim of this paper is the assessment of the possible impacts of eco-friendly fuels on injection systems by conducting tribological model tests. In this regard, lubricity (High-Frequency Reciprocating Rig, HFRR), scuffing load at different temperatures, and oxidation stability of different fuels B7, R33, pure HVO, and commercial-grade HVO diesel fuel have been deeply investigated. As a result of our study, the HFRR wear scar diameter (WSD) shows no distinct temperature dependence for both fossil-based diesel fuels (B7 and R33). In contrast, vegetable-based ones (pure HVO and commercially available HVO-based fuel) reveal lower lubricity with a trend to higher HFRR value when the temperature is increased. The commercial HVO fuel shows, compared to the pure HVO, better HFRR values at all tested temperatures. Nevertheless, all HFRR values still stay within the limits set by the relevant fuel standards EN 590 and ASTM D975.

Near-term advances in spark ignition (SI) engine technology (e.g., variable value lift [VVL], gasoline direct injection [GDI], cylinder deactivation, turbo downsizing) for passenger vehicles hold promise of delivering significant fuel savings for vehicles of the immediate future. Similarly, trends in transmissions indicate higher (8-speed, 9-speed) gear numbers, higher spans, and a focus on downspeeding to improve engine efficiency. Dual-clutch transmissions, which exhibit higher efficiency in lower gears, than the traditional automatics, and are being introduced in the light-duty vehicle segment worldwide. Another development requiring low investment and delivering immediate benefits has been the adaptation of start-stop (micro hybrids or idle engine stop technology) technology in vehicles today.

CHP power plants, supplied by natural gas, have a great interest due to more and more stringent environmental regulations. Natural gas has a low C/H ratio resulting in low CO2 emissions in spark ignition engines. For economical reasons, CHP gas engines are normally designed to operate under their optimal settings. Small variations in the composition of the supplied gas can then lead to knock occurrence. In this paper, a preventive knock device is developed for CHP power plants. It is based on the instantaneous measure of the Methane Number (MN) of the supplied gas. The measure is performed through an online MN gas sensor (it measures as well Wobbe index and the calorific value of the supplied gas). Prediction of knock, following the MN of the gas is developed in previous works. Correction of knock is performed through an engine map, established thanks to numerical simulations.

This paper focuses on the prediction of thermal losses and indicated performance in modern automotive engines. In a previous study, a complete simulation software was developed in order to both predict the car cabin blown air temperature and simulate the fluid circuits temperature. The two-zone, 0-dimensionnal combustion model presented in this paper aims to enhance this software. Theoretical overview reveals that thermal losses can be deduced from a predictive correlation of indicated performance. This correlation is established with a statistical tool and empirical coefficients are proposed. As a result of this study, the simulation software becomes a real-time computing tool that considers variable parameters previously neglected.

In modern passenger car diesel engines, multiple injection, MI, and rate shaping are measures, which in conjunction with others help to achieve the emissions legislation EU6 and US Tier2 Bin5. However, where hitherto mainly pollutant emissions where considered, CO2 output - i.e. fuel consumption - becomes increasingly important. Also, off cycle emissions may have to be regarded in the future. Additionally engine noise and drivability need consideration. The complexity and effect of an applied injection strategy is defined by the overall engine concept including the after treatment system, and also by the vehicle inertia. Additionally a modern fuel injection system not only has to allow for the necessary injection strategies but at the same time needs to offer robust performance over life time.

In modern passenger car diesel engines, multiple injection, MI, and rate shaping are measures, which in conjunction with others help to achieve the emissions legislation EU6 and US Tier2 Bin5. However, where hitherto mainly pollutant emissions where considered, CO2 output - i.e. fuel consumption - becomes increasingly important. Also, off cycle emissions may have to be regarded in the future. Additionally engine noise and drivability need consideration. The complexity and effect of an applied injection strategy is defined by the overall engine concept including the after treatment system, and also by the vehicle inertia. Additionally a modern fuel injection system not only has to allow for the necessary injection strategies but at the same time needs to offer robust performance over life time.

To reduce atmospheric CO2 emissions as well as crude oil consumption, several countries have started to increase the ethanol content in gasoline. Brazil is unique in this respect, where pure ethanol fuel (E100) is offered on the market, however the use of pure ethanol as a fuel, significantly affects engine oil dilution. High oil dilution directly affects the injection system, during the fuel evaporation process. The evaporation behaviour is mainly characterized by the chemical composition of the fuel accumulated in the oil, as well as the engine warm-up behaviour. A high proportion of the accumulated hydrocarbons in the engine oil evaporates, as engine oil temperature increases. There can be dramatic effects on systems that are not designed to consider the evaporated hydrocarbons. Effects such as misfire or engine stall are well known phenomena of unconsidered fuel evaporation.

A concept presented in this talk describes a preview of the digital map which can be used by other vehicle systems. The eHorizon Box (for electronic horizon) constantly sends small data packages via the vehicles data network (CAN bus). These packages contain information about the stretch of road ahead as well as topographic information. With this information, the engine control unit, the transmission control device or the driver assistance systems can optimize their respective functions. When eHorizon is used in commercial vehicles and passenger cars, Continental expects a reduction in fuel consumption, greater traffic safety and enhanced ride comfort. The eHorizon has numerous possible applications. Current engine management functions primarily use the available sensor data of the vehicle and for sure the individual driver impact. Based upon eHorizon's digital map data, the stretch of road ahead and its topography can be integrated in the strategy of the engine management.