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A constant volume combustion chamber (CVCC) was used to measure the flame speeds for various kinds of liquid hydrocarbon fuels, and an engine test was also carried out to obtain the relationship between combustion characteristics on the CVCC and the engine performance in an SI engine. In the engine test, it was confirmed that the fuel composition significantly affected the combustion stability under lean-burn conditions. From the relationship between the flame speed in the CVCC and the combustion duration in the test engine, we could find out the possibility of various kinds of fuels as the future fuel base.

Direct injection (DI) and jet ignition (JI), plus assisted turbocharging, have been demonstrated to deliver high efficiency, high power density positive ignition (PI) internal combustion engines (ICEs) with gasoline. Peak efficiency above 50% and power density of 340 kW/liter at the 15,000 rpm revolution limiter working overall λ=1.45 have been report-ed. Here we explore the further improvement in power density that may be obtained by replacing gasoline with ethanol or methanol, thanks to the higher octane number and the larger latent heat of vaporization, which translates in an increased resistance to knock, and permits to have larger compression ratios. Results of simulations are proposed for a numerical engine that uses rotary valves rather than poppet valves, while also using mechanical, rather than electric, assisted turbocharging. While with gasoline, the power density is 410-420 kW/liter, the use of oxygenates permits to achieve up to 475 kW/liter working with methanol.

Dielectric barrier discharges offer the advantage to excite molecules to reaction processes on a low temperature level in an O2 containing exhaust gas of gasoline or diesel engines. With the aim of a flexible coaxial reactor and a compact and efficient generator the influence of geometric and electric parameters on the reduction of exhaust gas components was determined. Geometric parameters studied were gap width, length, contour of the reactor. Electric parameters were: voltage curve, voltage height, frequency and electric power. Using the advantage of low temperature reactions it was possible to reduce the HC emission of a gasoline engine by about 35% within an electric power of 1000 W.

The NOx reduction performance under lean conditions over γ-alumina was evaluated using a micro-reactor system and a non-thermal plasma-equipped bench test system. Various alumina samples were obtained from alumina manufacturers to assess commercial alumina materials. In addition, γ-alumina samples were synthesized at Caterpillar with a sol-gel technique in order to control alumina properties. The deNOx performances of the alumina samples were compared. The alumina samples were characterized with analytical techniques such as inductively coupled plasma (ICP) emission spectroscopy, temperature programmed desorption (TPD) and surface area measurements (BET) to understand physical and chemical properties. The information derived from these techniques was correlated with the NOx reduction performance to identify key parameters of γ-alumina for optimizing materials for lean-NOx and plasma assisted catalysis.

Automotive manufacturers relentlessly explore engine technology combinations to achieve reduced fuel consumption under continued regulatory, societal and economic pressures. For example, technologies enabling advanced combustion modes, increased expansion to effective compression ratio and reduced parasitics continue to be developed and integrated within conventional and hybrid propulsion strategies across the industry. A high-efficiency gasoline engine capable for use in conventional or hybrid electric vehicle platforms is highly desirable. This paper is the second of two papers describing the multi-cylinder integration of a technology package combining lean-stratified combustion with Miller cycle for downsized boosted applications. The first paper describes the design, analysis and single-cylinder testing conducted to down-select the combustion system deployed to the multi-cylinder engine.

Automotive manufacturers relentlessly explore engine technology combinations to achieve reduced fuel consumption under continued regulatory, societal and economic pressures. For example, technologies enabling advanced combustion modes, increased expansion to effective compression ratio, and reduced parasitics continue to be developed and integrated within conventional and hybrid propulsion strategies across the industry. A high-efficiency gasoline engine capable for use in conventional or hybrid electric vehicle platforms is highly desirable. This paper is the first to two papers describing the development of a combustion system combining lean-stratified combustion with Miller cycle for downsized boosted applications. The work was completed under a multi-year US DOE project. The goal was to define a light-duty engine package capable of achieving a 35% fuel economy improvement at US Tier 3 emission standards over a naturally aspirated stoichiometric baseline vehicle.

Analysis of the thermodynamic cycle of IC engine from the point of view of economy and emissions was carried out. From this analysis potential capability of engine development was derived. This potential capability is lean-burn engine fueled with homogeneous mixture with λ ≥ 1,4. Several different modes of fueling were proposed and tested on one-cylinder test engine from the point of view of extending lean operating limit of the engine, emissions and fuel economy. Among them were: fueling with evaporated preheated gasoline, with gas (LPG evaporated) and with liquid butane. From these modes, fueling with liquid butane injected to inlet port was selected and finally tested. This novel system of fueling offered better than standard engine performances and emissions at lean operating limit. These results were validated on full-scale, two-cylinder engine.

Leaner lifted-flame combustion (LLFC) is a mixing-controlled combustion strategy for compression-ignition (CI) engines that does not produce soot because the equivalence ratio at the lift-off length is less than or equal to approximately two. In addition to completely preventing soot formation, LLFC can simultaneously control emissions of nitrogen oxides because it is tolerant to the use of exhaust-gas recirculation for lowering in-cylinder temperatures. Experiments were conducted in a heavy-duty CI engine that has been modified to provide optical access to the combustion chamber, to study whether LLFC is facilitated by an oxygenated fuel blend (T50) comprising a 1:1 mixture by volume of tri-propylene glycol mono-methyl ether with an ultra-low-sulfur #2 diesel emissions-certification fuel (CFA). Results from the T50 experiments are compared against baseline results using the CFA fuel without the oxygenate.

The car manufacturing process benefits from a competition between different materials that have to fulfil such demands as lightweight, comfort and safety. For ecological and economical reasons low vehicle weights minimise the energy consumption necessary for transportation. High strength steels enable to lower body weight by reducing sheet thickness and increase car safety by excellent crash behaviour. A very important contribution to vehicle safety and value maintenance during the whole life cycle is the use of galvanised steel sheets to prevent corrosion and premature failure of crash relevant body components. Up to date the high standards in corrosion protection and appearance of the exposed car body in the automotive industry are verified by extensive surface coating processes, applied to the body in white by batch processes. Continuous coil coating of galvanised sheet steel is an extremely efficient alternative to the currently used surface finishing processes.

The effective implementation of a lean supply chain, focusing on the key issues that ensure success. These include the ‘softer’ issues of involving logistics thinking in pre-production activities that have now become as important as the traditional ‘hard’ issues surrounding product delivery.

An aircraft propulsion system for Mach .6 flight is being developed which utilizes two turboshaft engines driving a pusher propeller through driveshafts and a combining gearbox. This system will provide greater operational safety as well as improved aircraft efficiency. This report describes design features, installation considerations, and operational characteristics of the system, and reviews methods of system analysis.

Flight certification for steep approach and landing at the increasingly popular London City Airport (LCY) offers commercial advantages for a business aircraft. The combined requirements of demonstrating 7.5° approach angle with a sink rate of less than 3 feet per second at touch down and the short runway present a special challenge to the certification team. Learjet's efforts to certify the M45 to the JAA NPA25-267 are described. It is shown that the M45 can meet the stringent requirements of the NPA with simple changes in the operational procedures, no aerodynamic modification, and increased level of safety compared to the more common approach seen with other business jets of landing with spoilers deployed. Suggestions on harmonization of steep approach guidance between the JAA/EASA, FAA, and TCCA are also provided.

Partially Premixed Combustion (PPC) has shown to be a promising advanced combustion mode for future engines in terms of efficiency and emission levels. The combustion timing should be suitably phased to realize high efficiency. However, a simple constant model based predictive controller is not sufficient for controlling the combustion during transient operation. This article proposed one learning based model predictive control (LBMPC) approach to achieve controllability and feasibility. A learning model was developed to capture combustion variation. Since PPC engines could have unacceptably high pressure-rise rates at different operation points, triple injection is applied as a solvent, with the use of two pilot fuel injections. The LBMPC controller utilizes the main injection timing to manage the combustion timing. The cylinder pressure is used as the combustion feedback. The method is validated in a multi-cylinder heavy-duty PPC engine for transient control.

The complex task of Vehicle Development (VD) has been a major challenge for automobile developers since its inception. The current approach to development is primarily resource based planning and execution. General Motors' Vehicle Engineering, with the help of MCA, has developed a fresh new approach to Vehicle Development. The new approach is a planning and execution philosophy that is focused on learning and prioritizing the learning. This approach has been applied to the development of vehicle performance attributes. In this paper, the authors will explain the fundamental philosophical and technical differences between the two approaches and illustrate the advantages of the new approach. The new approach relies heavily on usage of: 1 Zero Based Learning 2 Risk Prioritization and Sequencing 3 Mathematical Models and Problem Solving 4 Rapid Learning Cycles 5 Rapid Engineering Prototyping This paper will describe the scientific application of Learning Based Total Vehicle Development.

FOR a number of years the aircraft industry has employed a very worth-while tool in dealing with labor costs. This tool is popularly known as the “learning curve.” The learning curve traces the reduction in labor hours required for consecutive units produced. This paper discusses the various factors affecting production labor expenditure that determine the pattern of these curves, the mathematics of learning curves, and how learning curves can be used for estimating costs, forecasting labor requirements, predetermining production trends for control, and analyzing actual hour variations and trends. While these curves are based on aircraft experience, the author believes that the factors involved, and therefore the application of the theory, might well be adapted to any type of production.

In today’s race for improved fuel economy and lower emissions from gasoline engines, precise metering of delivered fuel is essential. Gasoline Direct Injection fuel systems provide the means for improved combustion efficiency through mixture preparation and better atomization. These improvements can be achieved from both increasing fuel pressure and using multiple injection events, which significantly reduce the required energizing time per injection, and in a number of cases, force the injector to operate at less than full stroke. When the injector operates in this condition, the influence of variation in injector dynamics account for a large percentage of the delivered fuel and require compensation to ensure accurate fuel delivery. Injector dynamics such as opening delay and closing time are influenced by operating conditions such as fuel pressure, energizing time, and temperature.

This work studied the control technique for the engine clutch engagement at launch for the TMED parallel HEV for the improved drivability and dynamic performance. Analysis are done on the speed synchronization of the clutch plates, the speed control using the starter motor (ISG), and the fluid pressure control for the clutch. Possible external factors such as changes in the friction coefficient of transmission fluid, temperature variation, auxiliary power and pressure losses are identified and their effects on the targeted dynamic performance are examined. The targeted system performance was achieved with a learning control technique using fluid pressure as the only control input. This involves the compensation for the effect of external factors on the fluid pressure profile and this effect is memorized for the subsequent slip-launch application.

This paper highlights a distinctive, highly-innovative, and project-based approach to supplying cutting-edge, market-driven and industry-focused education courses, at post-graduate level, in key motorsports engineering, business, and management subjects, using a highly-flexible, supported distance learning format. Such courses aim to deliver high-quality, usable knowledge to engineers, managers, and even drivers, with minimum disruption to their normal work patterns.

We are seeking to test and adapt successful devices for child crash protection from outside the United States not now used here. Test results and possible problems are presented for a transverse infant bed, a toddler backward facing seat, and an older child booster seat with back and head supports (from Kilppan, Sweden), and the Australian “Sit-Safe” design, an inexpensive belt to go between the shoulder strap and the lap belt to insure that the shoulder belt does not touch the child's neck. We have also tested an inflated pad alternative to the upper back of the front seat bulge passive restraint of DeRampe (France) to reduce knee contact - leg straightening - body vaulting which contributes to ejection of unrestrained people from the back seat. And we are testing plastic coated side glass to explore extending the anti-lacerative glazing advance of Saint-Gobain Vitrage (France) to the even more significant potential reduction of ejection.

Despite public expectations that autonomous vehicles should be able to avoid most accidents, the existing fleet of autonomous test vehicles has demonstrated this is simply not the case. An explanation for some of these accidents has been that these vehicles do not drive like humans and therefore do not exhibit certain driving patterns expected by human drivers. With the high likelihood of a gradual integration of autonomous vehicles into our traffic system in the future, there will be a need for such vehicles to adapt to, and mimic, human driving. Although much work has been done to understand human behavior and performance in driving, it has been mostly geared towards defining human capabilities and limitations. Little work has been done on the interactions between human-driven and autonomous vehicles.