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With growing demands for better fuel economy and reduced carbon emissions there is a need for smaller and more fuel efficient engines. At the same time, to improve passenger comfort there are also demands placed on improved vehicle quietness [1]. A Homogeneous Charge Compression Ignition (HCCI) system or a higher compression ratio system can be used to obtain better fuel economy but the enhanced combustion rate causes an increase in engine vibration in the medium to high frequency range [2, 3]. To ensure vehicle quietness, this issue of structure-borne noise that is transmitted from the engine mounts to the body must be addressed. In this paper a simple anti-vibration active mount system is introduced that can significantly reduce structure-borne noise at medium to high frequencies. This is achieved by adding mass to the insulator which leads to resonance at lower frequencies, in order to obtain double anti-vibration performance.

This paper describes the performance evolution and key breakthroughs of the world's first one-motor two-clutch (1M2CL) parallel full hybrid system without a torque converter that was developed and implemented on a hybrid luxury sedan in November 2010. The high potential of this hybrid system was brought out further to improve fuel economy without sacrificing acceleration performance. The resultant second generation of the 1M2CL parallel full hybrid system was applied to a hybrid premium sports sedan in August 2013. In order to improve these performance attributes, the following key technical measures were adopted: 1 Motor torque during the EV mode was increased to expand the EV drive region. 2 Maximum motor torque and battery power at engine startup were boosted to reduce the engine start time. 3 Integrated control of the motor and clutches was improved. 4 Mechanical efficiencies were improved for higher fuel economy.

A new highly biofidelic side impact dummy, the WorldSID 50th percentile male, has been developed under the supervision of the International Organization for Standardization in order to harmonize a number of existing side impact dummies in one single dummy. Momentum is growing for using the WorldSID in safety tests in the EU and the US. In the present study, two Euro-NCAP pole side impact tests were conducted to compare ES-2 and WorldSID responses in a mid-size SUV with respective seating positions as stipulated in the Euro-NCAP test conditions and fitted with the same side airbag. It was found that, compared with ES-2, the chest, abdomen and pelvis accelerations of WorldSID are more sensitive to variation in the applied external load transmitted by the deployed side airbag and door intrusion.

Implementation of appropriate safety measures, either from the viewpoint of a vehicle or the society or the infra-structure, it is an important issue to clearly understand the multi-dimension complicated real world accident scenarios. This study proposes a new method to easily capture and to extract the essence of such complicated multi-dimension mutual relationship by visualizing the results of SOM (Self Organizing Map). The FARS data from 2010 is used to generate a dataset comprised of 16,180 fatal passenger car drivers and 48 variables. The 16,180 fatal drivers were clustered using hierarchy cluster analysis method and mapped into a two-dimensional square with one dot representing one fatal driver using SOM.

This paper presents a combined experimental and numerical study of a modified Cooperative Fuel Research (CFR) engine that allows both the Research and Motor octane numbers (RON and MON) of any arbitrary Liquefied Petroleum Gas (LPG) mixture to be determined. The design of the modified engine incorporates modern hardware that enables accurate metering of different LPG mixtures, together with measurement of the in-cylinder pressure, the air-fuel ratio and the engine-out emissions. The modified CFR engine is first used to measure the octane numbers of different LPG mixtures. The measured octane numbers are shown to be similar to the limited data acquired using the now withdrawn Motor (LP) test method (ASTM D2623). The volumetric efficiency, engine-out emissions and combustion efficiency for twelve alternative LPG mixtures are then compared with equivalent data acquired with the standard CFR engine operating on a liquid fuel. Finally, the modified CFR engine is modelled using GT-Power.

We compare, with respect to vehicle characteristics (design, performance, fuel economy) and infrastructure requirements (cost of producing, transporting and delivering fuel), four possible energy carrier options for use with fuel cell vehicles: compressed hydrogen gas methanol with onboard steam reforming gasoline with onboard partial oxidation synthetic middle distillates (SMD) derived from natural gas with onboard partial oxidation. Our simulations indicate that hydrogen is the preferred fuel for fuel cell vehicles in terms of vehicle weight, simplicity, first cost and fuel economy. The total capital cost for equipment to bring hydrogen to the fuel cell (including both onboard fuel processors and off-vehicle fuel infrastructure) is comparable for methanol, gasoline and SMD, and lower for hydrogen.

A three-dimensional combustion model for a direct-injection stratified-charge rotary engine is used to identify modifications to the engine that should lead to better indicated efficiency. The engine has a single spark plug positioned alongside a single-hole pilot injector in a cavity located after the minor axis and a five-hole main injector that is located before the minor axis. It is predicted that a second ignition source located upstream of the main injector will lead to an increase in indicated efficiency of 6-8% if it ignites the mixture consistently. The computations were made at high and low engine speeds and loads, covering a significant part of the practical operating range of the engine. It is also predicted that the gain in efficiency of the engine with two ignition sources would be 7-10%, instead of 6-8%, if a two-hole pilot injector is also used instead of the one-hole pilot.

High-voltage nanosecond gas discharge has been shown to be an efficient way to ignite ultra-lean fuel air mixtures in a bulk volume, thanks to its ability to produce both high temperature and radical concentration in a large discharge zone. Recently, a feasibility study has been carried out to study plasma-assisted ignition under high-pressure high-temperature conditions similar to those inside an internal combustion engine. Ignition delay times were measured during the tests, and were shown to be decreasing under high-voltage plasma excitation. The discharge allowed instant control of ignition, and specific electrode geometry designs enabled volumetric ignition even at high-pressure conditions.

A correct prediction of the initial stages of the combustion process in SI engines is of great importance to understand how local flow conditions, fuel properties, mixture stratification and ignition affect the in-cylinder pressure development and pollutant formation. However, flame kernel growth is governed by many interacting processes including energy transfer from the electrical circuit to the gas phase, interaction between the plasma channel and the flow field, transition between different combustion regimes and gas expansion at very high temperatures. In this work, the authors intend to present a comprehensive, multi-dimensional model that can be used to predict the initial combustion stages in SI engines. In particular, the spark channel is represented by a set of Lagrangian particles where each one of them acts as a single flame kernel.

This paper describes a newly developed electrified powertrain that incorporates various energy-saving improvements and is intended for use on a 2013 model year EV. Based on a 2011 model year EV that was specifically designed and engineered as a mass-produced EV, this powertrain integrates the traction motor, inverter and charging unit to achieve a smaller, lighter package for expanding application to more vehicles. Integration of the motor and inverter in particular reduced the part count for enhanced assembly ease, in addition to reducing heat transfer, noise and vibration. The specific features described in the paper are the three points below. Improving the layout of the inverter parts in order to downsize and integrate the inverter with the motor. Reducing the transfer of heat from the motor to the inverter. Reducing the excitation forces of the motor and optimizing the inverter for noise and vibration.

A three-dimensional model for a direct injection stratified-charge rotary engine has been employed to study two modifications to the pocket geometry of the engine. In one modification, a pocket is located towards the leading edge of the rotor and is shown to produce recirculation within the pocket and faster burning. In the second modification, a two pocket rotor with two injectors and two spark plugs is studied. It appears that this should result in better utilization of the chamber air. It also appears that both modifications rhould result in higher efficiency of the direct-injected stratifiedcharge rotary engine. However extensive computations are required before a final conclusion is reached and before specific recommendations can be made.

Lateral control of a simulated vehicle in a simulated highway driving environment is explored. Three modules are used: a driving simulator, a visual preprocessor, and a neural network. The driving simulator, called RoadWay, is a three-dimensional computer graphics environment which supports interactive highway design and driving capabilities. The visual preprocessor, RoadVision, receives images from RoadWay, which represent forward-looking views from the cockpit of the simulated vehicle, and encodes these images using a family of oriented two-dimensional Gabor filters. Two Adaptive Resonance Theory neural network architectures, ART2 and ARTMAP, constituting the RoadBrain module, are employed to learn mappings between the visual encodings and emergent image categories, and then to associate these image categories with appropriate steering decisions.

Results are presented of two-dimensional computations of air-assist fuel injection into engines with bowl-in-piston and bowl-in-head, with and without swirl and for early and late injection but without combustion. The general finding is that swirl tends to destroy the head vortex of the air/fuel jet and results in a faster collapse of the spray cone toward its axis. Faster collapse is also promoted by high density of the chamber gas (e.g. late injection) and bowl-in-head design (limited availability of chamber gas around the spray, presence of walls and delayed influence of squish by the injector). With enhanced collapse, fuel-rich regions are formed around the axis and away from the injector. With reduced collapse, the radial distribution of the fuel is more uniform. Thus swirl tends to lead to both slower vaporization and richer vapor mixtures. Also, with strong swirl the rich mixtures tend to end up by the injector; without swirl, by the piston.

Results are presented of 3-D computations of direct injection of gaseous methane and of liquid tetradecane through a multi-hole injector into a Diesel engine. The study focusses on the distribution of fuel/air ratio within the resulting gas and spray jets under typical Diesel conditions prior to ignition. It is shown that for a significant time after start of injection, the fraction of the vapor fuel which is in richer-than-flammable mixtures is greater in gas jets than in sprays. For methane injection, it is also shown that changing some of the flow conditions in the engine or going to a poppet-type injector, does not result in improved mixing. An explanation of these results is provided also through an analysis of the self-similar gas jet and 2-D computations of gas and spray jets into constant pressure gas. A scaling for time and axial distance in the self-similar gas jet also clarifies the results.

Results of experiments performed on a direct-injection two-stroke engine using an air-assisted injector are presented. Pressure measurements in both the engine cylinder and injector body coupled with backlit photographs of the spray provide a qualitative understanding of the spray dynamics from the oscillating poppet system. The temporal evolution of the spatial distribution of both liquid and vapor fuel were measured within the cylinder using the Exciplex technique with a new dopant which is suitable for tracing gasoline. However, a temperature dependence of the vapor phase fluorescence was found that limits the direct quantitative interpretation of the images. Investigation of a number of realizations of the vapor field at a time typical of ignition for a stratified-charge engine shows a high degree of cycle to cycle variability with some cycles exhibiting a high level of charge stratification.

Efforts are reported to reproduce the distribution of liquid and vapor fuel from a pulsating hollow-cone liquid-only injector measured by the planar exciplex technique within the head cup of a motored ported single-cylinder engine operated at 1600 rpm with high swirl and a squish ratio of 75%. The injector, cup and cylinder were coaxial. The measurements show that shortly after the beginning of the injection the maximum liquid and vapor fuel concentrations are along the axis but also that the spray achieves substantial radial and axial penetrations. The engine flowfield without injection had previously been characterized by LDV and PIV and so had been the injector and its spray in constant pressure environments so that little arbitrariness was left in reproducing the spray in the engine. Two spray models were used. In one the large drops produced by the break up of the liquid sheet were introduced into the numerical field at the injector exit nearly with the poppet seat angle.

A second effort is reported to reproduce the distribution of fuel from a pulsating hollow-cone liquid-only poppet injector measured by the planar exciplex technique within the head cup of a motored ported single-cylinder engine operated at 1600 rpm with high swirl and a squish ratio of 75%. The injector, cup and cylinder were coaxial. The engine flowfield without injection had previously been characterized by LDV and PIV and so had been the injector and its spray in constant pressure environments. In a previous effort, the injector was assume to generate drop and the computed collapse of the spray was found to be too slow. In this work, the injector is assumed to generate liquid sheets that change shape and produce drops from their leading edges and surfaces as they propagate through the gas.

Simultaneous fuel distribution images (by shadowgraph and laser-induced fluorescence) and cylinder pressure measurements are reported for a combusting stratified-charge engine with a square cup in the head at 800 RPM and light load for two spark locations with and without swirl. Air-assisted direct-injection occurred from 130°-150° after bottom dead center (ABDC) and ignition was at 148° ABDC. The engine is ported and injection and combustion take place every 6th cycle. The complicated interaction of the squish, fuel/air jet, square cup, spark plug geometry and weak tumble gives rise to a weak crossflow toward the intake side of the engine with no swirl, but toward the exhaust side in the presence of strong swirl, skewing the spray slightly to that side.

Laser induced fluorescence from a dye contained in Unocal RF-A gasoline was excited using 355nm light and the resulting fluorescence imaged (λ>420nm). In order to minimize the changes to the intake geometry the fluorescence was collected by a fiberoptic probe with an articulatible tip. The collected light was imaged onto an intensified CCD camera synchronized with the laser, which was timed to illuminate the intake port after the completion of injection. Cold-starts from 20°C were conducted on an engine dynamometer test stand with two fuel systems: pintle-type port fuel injection, and air-forced port fuel injection. When the injection timing and initial enrichment were optimized the transient emissions from the air-forced system were significantly reduced compared with the conventional system.

Engine-out, cold-start (from 20°C) UHC emissions from a contemporary 2.0 4-cylinder engine with swirl control were measured with FID and FT-IR. The steady-state, end of test operation was 1500 rpm, 2.6 bar BMEP (25% load) and stoichiometric mixture. Four fuel systems were employed pintle-type port-injected gasoline, air-forced port-injected gasoline, port-injected propane, and premixed propane. These fuel systems were chosen to separate effects of fuel atomization, vaporization, and fuel-air mixing. Each system was optimized with respect to injector targeting, injection timing, mixture enrichment, and spark advance. Open-valve injection timing increased UHC emissions more with the pintle-type injector than with the air-forced, system. UHC emissions with propane injection were minimized with open valve injection.