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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.

A zero-dimensional heat release model was developed for compression ignition engines. This type of model can be utilized for parametric studies, off-line optimization to reduce experimental efforts as well as model-based control strategies. In this particular case, the combustion model, in a simpler form, will be used in future efforts to control the combustion in compression ignition engines operating on gasoline-like fuels. To allow for a realistic representation of the in-cylinder combustion process, a spray model has been employed to allow for the quantification of fuel distribution as well as turbulent kinetic energy within the injection spray. The combustion model framework is capable of reflecting premixed as well as mixing controlled combustion. Fuel is assigned to various combustion events based on the air-fuel mixture within the spray.

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 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.

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.

Virtual NVH Engineering is going to be reviewed in this paper for the development of FIE (fuel injection equipment) components. Some examples based on high pressure pumps and SCR air cooling injectors will illustrate the explanation. The use of a 3D FEM vibro-acoustic model is essential to support virtual NVH Engineering. Therefore, a review of techniques to study components is done first. Model correlation is also an important topic which will be discussed and which makes any NVH engineer confident in using a model instead of real HW. It is quite challenging to establish these models, as they must mimic the entire physical phenomenon of real structure borne hardware sound in the whole audible frequency range. Limitations of models are also identified and allow answering one true question: Should we stay considering only each component separately or as an assembly of parts of a larger system in the development process?

Heat loss through wall boundaries play a dominant role in the overall performance and efficiency of internal combustion engines. Typical engine simulations use constant temperature wall boundary conditions [1, 2, 3]. These boundary conditions cannot be estimated accurately from experiments due to the complexities involved with engine combustion. As a result, they introduce a large uncertainty in engine simulations and serve as a tuning parameter. Modeling the process of heat transfer through the solid walls in an unsteady engine computational fluid dynamics (CFD) simulation can lead to the development of higher fidelity engine models. These models can be used to study the impact of heat loss on engine efficiency and explore new design methodologies that can reduce heat losses. In this work, a single cylinder diesel engine is modeled along with the solid piston coupled to the fluid domain.

Durability assessments of modern engines often require accurate modeling of thermal stresses in critical regions such as cylinder head firedecks under severe cyclic thermal loading conditions. A new methodology has been developed and experimentally validated in which transient temperature distributions on cylinder head, crankcase and other components are determined using a Conjugate Heat Transfer (CHT) CFD model and a thermal finite element analysis solution. In the first stage, cycle-averaged gas side boundary conditions are calculated from heat transfer modeling in a transient in-cylinder simulation. In the second stage, a steady-state CHT-CFD analysis of the full engine block is performed. Volume temperatures and surface heat transfer data are subsequently transferred to a thermal finite element model and steady state solutions are obtained which are validated against CFD and experimental results.

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.

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.

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 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.

Diesel aided by gasoline low temperature combustion offers low NOx and low soot emissions, and further provides the potential to expand engine load range and improve engine efficiency. The diesel-gasoline operation however yields high unburned hydrocarbons (UHC) and carbon monoxide (CO) emissions. This study aims to correlate the chemical origins of the key hydrocarbon species detected in the engine exhaust under diesel-gasoline operation. It further aims to help develop strategies to lower the hydrocarbon emissions while retaining the low NOx, low soot, and efficiency benefits. A single-cylinder research engine was used to conduct the engine experiments at a constant engine load of 10 bar nIMEP with a fixed engine speed of 1600 rpm. Engine exhaust was sampled with a FTIR analyzer for speciation investigation.

Powertrain Systems development is entering a period of unprecedented challenge driven by the convergence of many factors: increasing government regulations for both tailpipe emissions and fuel economy, increased competition, reduced workforce, and tighter program budgets. This has resulted in timing compression and resource reduction that stress a typical Design-Build-Test development practice. The application of telematics and information technology to engineering development can provide the efficiency gains required for engineers to deliver a robust powertrain system in a timely manner. By automating the evaluation of a system's robustness, engineers can focus their time on problem areas during their normal development process and launch with quality. This paper will detail how this methodology was jointly applied by Control-Tec and Navistar to identify and improve system performance before production.

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.

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.

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.

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.