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Back in the first two decades of automobile development, electric propulsion was a serious competitor for the internal combustion engine. Electrically-propelled vehicles, however, soon proved unable to satisfy users' increasing performance demands in terms of range, acceleration, top speed and hill-climbing, together with such factors as operating life, initial purchase price, running costs and reliability. Engineers investigating electric propulsion today face precisely the same unwelcome legacy as their predecessors, despite many and varied attempts in the meantime to improve the components of the electric vehicle's drive system (energy storage device, motors, controller). Progress in battery development, particularly in the case of the NaS system, has nevertheless enabled us at least partly to overcome the previous problems associated with electric drive systems, though it cannot be claimed that all obstacles to its commercial application have been eliminated as yet.

In order to study the soot formation and oxidation phenomena during the combustion process of Gasoline Direct Injection (GDI) engines, soot volume fraction measurements were performed in an optical GDI engine by combined Laser-Induced Incandescence (LII) and Laser Extinction Method (LEM). The coupling of these two diagnostics takes advantages of their complementary characteristics. LII provides a two-dimensional image of the soot distribution while LEM is used to calibrate the LII image in order to obtain soot volume fraction fields. The LII diagnostic was performed through a quartz cylinder liner in order to obtain a vertical plane of soot concentration distribution. LEM was simultaneously performed along a line of sight that was coplanar with the LII plane, in order to carry out quantitative measurements of path-length-averaged soot volume fraction. The LII images were calibrated along the same path as that of the LEM measurement.

Over the next decades to come, fossil fuel powered Internal Combustion Engines (ICE) will still constitute the major powertrains for land transport. Therefore, their impact on the global and local pollution and on the use of natural resources should be minimized. To this end, an extensive fundamental and practical study was performed to evaluate the potential benefits of simultaneously co-optimizing the system fuel-and-engine using diesel as an example. It will be clearly shown that the still unused co-optimizing of the system fuel-and-engine (including advanced exhaust after-treatment) as a single entity is a must for enabling cleaner future road transport by cleaner fuels since there are large, still unexploited potentials for improvements in road fuels which will provide major reductions in pollutant emissions both in vehicles already in the field and even more so in future dedicated vehicles.

In order to avoid the undesired side effect of water condensation occurring under special environment conditions in modern xenon lamps several modifications of the serial automotive headlamps were suggested. The suggestions consist of a) desired leakage in the cover, b) anti-fog coating and c) integrated ventilation tube. These strategies were tested using two types of serial head lamps applying a condensation cycle for the simulation of the urban condition. During this condensation cycle the thermodynamic parameters, like relative air humidity and temperature, were measured at different places in the head lamp and as function of time. The modification with the integrated ventilation tube is able to improve the serial head lamp significantly. The improvement in terms of water condensation for the modification using anti-fog coating depends from the number of cooling cycles.

In-cylinder absorption and desorption of fuel by lubricating oil films is assumed to be among the main sources of unburned hydrocarbon emissions from spark ignition engines. As this phenomenon is mainly conditioned by the solubility of fuel in lubricant, differences in hydrocarbon emission levels were measured running an automotive engine, with various couples of singular constituent fuels and lubricants. In this way it was found that lowering the solubility by a factor of 40 caused an average HC emission reduction of 30%. It was found too that with commercial unleaded fuels the lubricant constitution had little influence on the emissions. As this fact was difficult to explain, and because the gasoline solubility values are not available, a single cylinder engine with an extended piston was specially designed to run with or without oil between the cylinder liner and the piston rings. The experimental method has been validated using an insoluble gaseous fuel (propane).

This paper is the third in the series of documents designed to record the progress on the SAE Plug-in Electric Vehicle (PEV) communication task force. The initial paper (2010-01-0837) introduced utility communications (J2836/1™ & J2847/1) and how the SAE task force interfaced with other organizations. The second paper (2011-01-0866) focused on the next steps of the utility requirements and added DC charging (J2836/2™ & J2847/2) along with initial effort for Reverse Power Flow (J2836/3™ & J2847/3). This paper continues with the following: 1. Completion of DC charging's 1st step publication of J2836/2™ & J2847/2. 2. Completion of 1st step of communication requirements as it relates to PowerLine Carrier (PLC) captured in J2931/1. This leads to testing of PLC products for Utility and DC charging messages using EPRI's test plan and schedule. 3. Progress for PEV communications interoperability in J2953/1.

Automatic Crash Notification (ACN) technology provides an opportunity to rapidly transmit crash characteristics to emergency care providers in order to improve timeliness and quality of care provided to occupants in the post crash phase. This study evaluated the relative value of crash attributes in providing useful information to assist in the identification of crashes where occupants may be seriously injured. This identification includes an indication of whether a crash is likely to require a level of emergency response with higher priority than is needed for most crashes reported by ACN Systems. The ability to predict serious injury using groupings of variables has been determined. In this way, the consequence of not transmitting each variable can be estimated. In addition, the incremental benefit of voice communication is shown.

Laboratory experiments were conducted to evaluate a commercial Pd/Rh three-way catalyst as regards its effectiveness in the catalytic oxidation of hydrocarbons (HC) under conditions encountered in spark ignition engine exhaust (air/fuel ratio = 14.7). These tests aimed to determine light-off temperatures (50 % conversion temperatures) for HC, CO and NO in mixtures containing CO2, H2O, H2, CO, NO, O2, N2 and one hydrocarbon. First, the effect of the concentration of different compounds (H2O, H2, CO, NO) on the catalytic oxidation of propane was studied. The oxidation of the most important HC species, i.e. alkanes (C1 to C7), alkenes (C2 to C6), alkenes (C2 to C6) and aromatics (C6 to C9), was then investigated. The results were compared to those obtained with a Pt/Rh catalyst. The inhibiting effect of hydrocarbons as concerns CO oxidation and NO reduction was finally examined.

The implementation of the IFP developed Compressed Air Assisted Fuel Injection Process (named IAPAC) in a two-stroke engine allows the introduction of the fuel separately from the scavenging air, which in consequence minimizes fuel short-circuiting. The inherent mechanical principle of the IAPAC process which uses the crankcase compressed air to finely atomize the fuel, provides the advantages of direct injection but in addition uses conventional low pressure automotive type injection technology with commercially available gasoline injectors. In earlier work we showed an example of the application of this fuel injection technology to a PIAGGIO single cylinder 125 cc scooter two-stroke engine. In this paper, an update of the results obtained with this new engine is presented and confirms the ultra-low emissions capability for two-wheeler application.

The purpose of this study is to determine if inhomogeneous mixing of EGR and fresh air in the intake ports can lead to a specific spatial distribution of burnt gases in the combustion chamber before ignition. To achieve this goal, several three dimensional computations of a multi-valve, spark ignited engine with a dual intake ports are performed. We study the effect of engine speed (1500 and 3000 rpm), the effect of flow structure and turbulence (one and two operating intake valves) and the effect of the EGR intake technology (in the plenum or in each intake runner). Three dimensional computations are performed with a new version of the KMB code. Numerical improvements (iterative solver. convection scheme …), new sub-models (turbulence, beat transfer and law of the wall), as well as a multi-block strategy with mesh refinement algorithm were developed and implemented in the code. These improvements allow complicated geometries to be modeled.

The theory presented here allows forecasting of nitric oxide emissions in spark ignition engines. Following preliminary review of possibilities of obtaining the equilibrium state, as well as the basic concept of medium temperatures, the authors suggest using kinetic calculations for estimating the NO content of both unburned and burned mixtures. After good correlation is obtained, particularly for lean mixtures, the calculation is used to determine the best combustion process by simulation on a computer. Since experiments show an important effect of the fuel-air heterogeneity, complementary simulating work is conducted in order to define the best fuel stratification laws.

A study based on both three dimensional modelling of the internal flow and velocity measurements using Laser Doppler Velocimetry in a four-valve spark ignition engine was carried out. Two different optical arrangements, allowing three velocity component measurements, were used. The intake and the compression strokes were computed and comparisons between computations and experiments were performed for three intake configurations. In configuration for which two intake valves are opened, specific computational difficulties arise and no satisfactory agreement is achieved. However, when only one intake valve is opened, the computed and measured velocity profiles are found to agree relatively well. In the basic configuration, the internal flow is characterized by a tumbling motion. The combination with swirl in the two other configurations leads to the generation of complex flow structures which can be described as inclined tumble.

BMW has undertaken a comprehensive program including laboratory simulation rig tests, engine dynamometer and fleet evaluations to evaluate the influence of mechanical and fuel variables on induction system deposits in modern port fuel injected (PFI) spark ignition engines. The primary focus of the program has been the deposit buildup on intake valves (IVD) and associated driveability impacts. Initial investigations of engine modifications yielded only marginal improvements relative to deposit build-up and, therefore this led to investigations of the effect of gasolines and additives. Fuel quality, type, quantity of additives and alcohol content have all been found to be major contributing factors to intake valve deposition. In addition, intake valve deposit weight has been directly related to warm-up phase driveability concerns using a newly developed driveability procedure.

The idea of keeping a vehicle safe and secure throughout its whole life cycle, as well as having the opportunity to add functionality after initial delivery, is the key motivation behind automotive software updates. Today, safety or security issues that appear after vehicle delivery need to be resolved by starting a recall campaign. These campaigns require the vehicle user to visit a car repair workshop to get an update. Over The Air (OTA) software updates, being location-independent, can pave the way for higher update frequencies and more efficiency regarding customer satisfaction, resource consumption as well as safety and security. In this paper we analyze requirements for OTA software updates phrased in various standards and regulations as well as in existing development and type approval processes. Prevailing challenges for OTA updates are extracted to identify necessary activities and artifacts within the procedure.

This paper summarises the potential for the use of a gasoline direct injection engine for fuel economy benefits. Various engine technologies are compared for the greatest reduction in fuel consumption at the steady state point 2000rpm/2 bar. This is an important driving point in the EU cycle. The direct injection engine when used in an unthrottled lean stratified mode shows the greatest potential. Calculations show a fuel economy of a middle class vehicle can be increased by 12% using a DI over the EU cycle. The catalytic aftertreatment system is discussed and it is concluded that a close coupled pre-catalyst, a NOx trap and double injection are a good overall solution for the minimisation of exhaust gas emissions from a DI engine.

Interest has been growing in many countries in the potential use of diesel particulate filters (DPF). This type of after treatment technology has been shown to make very significant reductions in both the mass of particulate emitted in diesel exhaust gas, and also in the number of fine particulates, which have been linked in recent years with concerns for human health. Work carried out during a development programme investigating the capability of fuel soluble metallic additives to assist DPF regeneration, indicated superior performance from a novel combination of metals in fuel soluble form. Earlier work showed that a fuel soluble combination of organo-metallic additives based on sodium and strontium gave very effective regeneration characteristics, and was capable of burning out carbon at temperatures from about 160°C.

To reduce vehicle development cycles it is necessary to perform numerical durability analyses in an early development phase. Typically there is no physical prototype available at that time hence there are no measured data, either from the proving ground or from test rigs. This paper presents an alternative method to predict the required loads. Using Multi-Body Simulation (MBS), the loads prediction process is performed for an unconstrained vehicle, which means that vehicle body position and orientation are allowed to change. Of particular interest are the time series of the loads acting at components of the front-and the rear-suspension, as well as on the body structure of the vehicle. For the loads prediction BMW uses the so called Hybrid-Road-Approach developed by LMS. After an initial pilot project demonstrating that approach's feasibility and potential, the project presented below is the first run of that approach by BMW in their productive environment.