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In the field of passenger car engines, recent research advances have proven the effectiveness of downsized, turbocharged and direct injection concepts, applied to gasoline combustion systems, to reduce the overall fuel consumption while respecting particularly stringent exhaust emissions limits. Knock and turbocharger control are two of the most critical factors that influence the achievement of maximum efficiency and satisfactory drivability, for this new generation of engines. The sound emitted from an engine encloses many information related to its operating condition. In particular, the turbocharger whistle and the knock clink are unmistakable sounds. This paper presents the development of real-time control functions, based on direct measurement of the engine acoustic emission, captured by an innovative and low cost acoustic sensor, implemented on a platform suitable for on-board application.

It is well known that mufflers attenuate the engine noise essentially through dissipative and reflective effects. There is however another alternative technique for noise attenuation that has not been deeply explored, i.e. thermal acoustics. In fact the temperature of the gas influences the acoustic behaviour of the exhaust system; reducing the exhaust gas temperature, the sound pressure of the acoustic waves is reduced. This phenomenum could be used to improve the sound attenuation. We propose an experimental study of this phenomenum and of how it could be used to reduce the exhaust noise. We measured that, using in underfloor position passive heat exchangers like corrugated pipes, the exhaust gas quickly exchanges heat with the external environment and arrives to the rear muffler significantly colder. We observe about 2 dB decrease of the OA dB value when the gas temperature decreases of about 100°C.

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.

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.

The paper presents the main reasons for the increasing market share of vehicles with the capacity to run on random bio fuel blends. It describes the philosophy and basic layout of current integral flex mixture preparation systems. The paper demonstrates the necessity to introduce a series of new high-performance analysis tools for further improvement of the mixture preparation system and in particular the fuel injector performance. The paper continues with a discussion of the basic structure of the interactive Virtual Engine Model approach applied to fuel injector atomizer optimization. Test results obtained by application of the new tools to two different series production flex engines are presented. The impact of the improved spray formation capability of the optimized fuel injector atomizers is explained and experimental vehicle FTP-cycle data are reported and discussed.

This paper documents an extensive study aimed at a better understanding of the peculiarities and performance of crankshaft mounted gerotor pumps for IC engines lubrication. At different extents, the modelling, simulation and testing of a specific unit are all considered. More emphasis, at the modelling phase, is dedicated to the physical and mathematical description of the flow losses mechanisms; the often intricate aspects of kinematics being deliberately left aside. The pressure relief valve is analysed at a considerable extent as is the modelling of the working fluid, a typically aerated subsystem in such applications. Simulation is grounded on AMESim, a relatively novel tool in the fluid power domain, that proves effective and compliant with user deeds and objectives. Testing, at steady-state conditions, forms the basis for the pro!gressive tuning of the simulation model and provides significant insight into this type of volumetric pump.

A unique differential assembly was needed for the Lawrence Technological University (LTU) SAE Formula race car. Specifically, a differential was required that had torque sensing capabilities, perfect reliability, high strength, light weight, the ability to withstand inertia and shock loading, a small package, no leaks, the ability to support numerous components. In that regard, an existing differential was selected that had the torque sensing capabilities, but had deficiencies that needed to be fixed. Those deficiencies included the following: Differential unit was over 4 kg unmounted, with no housing. This was considered too heavy, when housed properly. Bearing surface was provided on only one end of the carrier. This design provides insufficient bearing surface to support either the differential housing or half-shafts The internal drive splines integral to the case are not optimized for a perpendicular drive/axle arrangement, such as, a chain drive.

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.

Proper design of the combustion phase has always been crucial for Diesel engine control systems. Modern engine control strategies' growing complexity, mainly due to the increasing request to reduce pollutant emissions, requires on-board estimation of a growing number of quantities. In order to feedback a control strategy for optimal combustion positioning, one of the most important parameters to estimate on-board is the angular position where 50% of fuel mass burned over an engine cycle is reached (MFB50), because it provides important information about combustion effectiveness (a key factor, for example, in HCCI combustion control). In modern Diesel engines, injection patterns are designed with many degrees of freedom, such as the position and the duration of each injection, rail pressure or EGR rate. In this work a model of the combustion process has been developed in order to evaluate the energy release within the cylinder as a function of the injection parameters.

People make judgements of the sound produced by vehicles in a variety of situations and contexts. The most common type of assessment is an overall judgement of sound quality like pleasantness and sportiveness. From the car manufacturer''s point of view it is important to note that subjective judgements of sound influence the buyer''s opinion of the performance and value of the vehicle. Consequently, there is a need to quantify the subjective perception of the sound quality associated with a vehicle. This paper presents a study of the sound quality of vehicle exhaust noise based on the correlation between the subjective perception associated with this type of sound and measured psycho-acoustic parameters such as loudness, sharpness and roughness. The tailpipe noise of a selection of representative vehicles was recorded using an artificial head. A subjective evaluation of these sound recordings was made by a jury using standard relative techniques.

Experimental measurements and numerical computations were made to characterize a spray generated by a high-pressure swirl injector. The Phase Doppler technique was applied to get information on droplet sizes (d10) and axial velocities at defined distances from the injector tip. Global spray visualization was also made. Computations were carried out using a modified version of KIVA 3V. In particular, the break-up length of the sheet and its dimension were computed from a semi-empirical correlation related to the wave instability theory suggested by Dombrowski, including the modifications introduced by Han and Reitz. Two different approaches were used to describe the initial spray conditions. According to the first, discrete particles with a characteristic size equal to the thickness of the sheet are injected. The second approach assumes, that the particles having a SMD computed by a semi-empirical correlation are injected according to a statistical distribution.

The first part of the paper gives an overview of the results obtained with European GDI-powered vehicles launched on the market. Thereafter, a discussion of in-vehicle limitations due to the exhaust gas after-treatment system requirements is given. The paper continues with a description of the current development status of European lean stratified direct injection system layouts. A detailed presentation is made of the mixture preparation system key components, basic control algorithms and the necessary new high-level experimental and analytical development tools. Particularly the topic of the multi-purpose use of 3-D numerical simulation is addressed both in the development and the engine control strategy calibration phases. The development of a small 1.6 liter lean stratified engine project is taken as example to demonstrate the dual application capability of the 3D simulation tool.

The paper reports on the optical investigation of a multiple spark ignition system carried out in a closed vessel in inert gas, and in an optical access engine in firing condition. The ignition system features a plug-top ignition coil with integrated electronics which is capable of multi-spark discharges (MSD) with short dwell time. First, the ignition system has been characterized in constant ambient conditions, at different pressure levels. The profile of the energy released by the spark and the cumulated value has been determined by measuring the fundamental electrical parameters. A high speed camera has been used to visualize the time evolution of the electric arc discharge to highlight its shape and position variability. The multiple spark system has then been mounted on an optical access engine with port fuel injection (PFI) to study the combustion characteristics in lean conditions with single and multiple discharges.

The development of suspension systems has seen substantial improvements in the last years due to the use of variable dampers. Furthermore, the efficiency increase in the subsystems within the automotive chassis has led to the use of regenerative solutions, in which electric machines can be employed as generators to recover part of the energy otherwise dissipated. However, the harvesting capability of regenerative suspensions is often limited by friction and inertial phenomena. The former ones waste mechanical energy into heat, while the latter ones hamper the shock absorption by locking the suspension when subject to dynamic excitation. Besides a suitable design and sizing of components, recent research works highlight the use of the so-called motion rectifier to improve energy recovery by constraining the motion of the electric motor to a single sense of rotation.

An exhaust system comprises at least one muffler, the back pressure generated by the muffler exponentially grows as the engine speed increases. Accordingly, fuel consumption and direct CO2 emissions are penalized due to the back pressure generated by the muffling body in order to reduce noise emissions. To obviate this, it has been suggested to construct an exhaust system with two differentiated paths according to the engine speed, so that at low speeds the exhaust gases follow a first high acoustic attenuation (high back pressure) path, while at high speeds (high exhaust gas pressure), the exhaust gases follow a second low acoustic attenuation (low back pressure) path. Simulation and experimental analysis will be presented. A control valve is provided to alternatively direct the exhaust gases along the desired path according to the engine speed. These control valves usually include an electric or electro-pneumatic actuator, but are heavy, large in size and expensive.

In modern Diesel engine control strategies the guideline is to perform an efficient combustion control, mainly due to the increasing request to reduce pollutant emissions. Innovative control algorithms for optimal combustion positioning require the on-board evaluation of a large number of quantities. In order to perform closed-loop combustion control, one of the most important parameters to estimate on-board is MFB50, i.e. the angular position in which 50% of fuel mass burned within an engine cycle is reached. Furthermore, MFB50 allows determining the kind of combustion that takes place in the combustion chamber, therefore knowing such quantity is crucial for newly developed low temperature combustion applications (such as HCCI, HCLI, distinguished by very low NOx emissions). The aim of this work is to develop a virtual combustion sensor, that provides MFB50 estimated value as a function of quantities that can be monitored real-time by the Electronic Control Unit (ECU).

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.

The paper presents a study made to define the optimal parameter configuration, which enables the mixture preparation, and ignition systems to perform a low-temperature engine start by pure ethanol fuelling without misfiring or failure. A numerical virtual engine, simulating the behavior of a real small displacement 8 valves passenger car engine, is set up to describe and understand the physical phenomena of mixture preparation, spatial and temporal in-cylinder mixture distribution and the ignition/combustion events. The complex phenomena, which govern the gas flow patterns and mixture formation in the intake port and the combustion chamber are particularly analyzed during low-temperature engine cranking. Furthermore is discussed the influence of open and closed valve injection modes.

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.