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The aim of the paper is the comparison of the injection process with different fuels, i.e. a standard diesel fuel and a pure biodiesel. Multiphase cavitating flows inside diesel nozzles are analyzed by means of unsteady CFD simulations using a two-fluid approach with consideration of bubble dynamics, on moving grids from needle opening to closure. Two five-hole nozzles with cylindrical and conical holes are studied and their behaviors are discussed taking into account the different properties of the two fuels. Extent of cavitation regions is not much affected by the fuel type. Biodiesel leads to significantly higher mass flow only if the nozzle design induces significant cavitation which extends up to the outlet section and if the injector needle is at high lift. If the internal hole shaping is able to suppress cavitation, the stabilized mass flows are very similar with both fuels.

Existing gasoline DI injection equipment has been modified to generate single hole pulsed gas jets. Injection experiments have been performed at combinations of 3 different pressure ratios (2 of which supercritical) respectively 3 different hole geometries (i.e. length to diameter ratios). Injection was into a pressure chamber with optical access. Injection pressures and injector hole geometry were selected to be representative of current and near-future DI natural gas engines. Each injector hole design has been characterized by measuring its discharge coefficient for different Re-levels. Transient jets produced by these injectors have been visualized using planar laser sheet Mie scattering (PLMS). For this the injected gas was seeded with small oil droplets. The corresponding flow field was measured using particle image velocimetry (PIV) laser diagnostics.

Simultaneous crank-angle-resolved measurements of gasoline concentration and gas temperature were made with two-color mid-infrared (mid-IR) laser absorption in a production spark-ignition engine (Nissan MR20DE, 2.0L, 4 cyl, MPI with premium gasoline). The mid-IR light was coupled into and out of the cylinder using fiber optics incorporated into a modified spark plug. The absorption line-of-sight was a 5.3 mm optical path located closely adjacent to the ignition spark providing spatially resolved absorption. Two sensor wavelengths were selected in the strong bands associated with the carbon-hydrogen (C-H) stretching vibration near 3.4 μm, which have an absorption ratio that is strongly temperature dependent. Fuel concentration and temperature were determined simultaneously from the absorption at these two wavelengths.

This study investigates the impact of mid-high biodiesel blends on the criteria and PAH emissions from a modern pick-up diesel vehicle. The vehicle was a Euro 4 (category N1, subclass III) compliant common-rail light-duty goods pick-up truck fitted with a diesel oxidation catalyst. Emission and fuel consumption measurements were performed on a chassis dynamometer equipped with CVS, following the European regulations. All measurements were conducted over the certification New European Driving Cycle (NEDC) and the real traffic-based Artemis driving cycles. Aiming to evaluate the fuel impact on emissions, a soy-based biodiesel, a palm-based biodiesel, and an oxidized biodiesel obtained from used frying oils were blended with a typical automotive ultra-low-sulfur diesel at proportions of 30, 50 and 80% by volume. The experimental results revealed that CO₂ emissions and fuel consumption exhibited an increase with biodiesel over all driving conditions.

Conventional diesel fuel has been in the market for decades and used successfully to run diesel engines of all sizes in many applications. In order to reduce emissions and to foster energy source diversity, new fuels such as alternative and renewable, as well as new fuel formulations have entered the market. These include biodiesel, gas-to-liquid, and alternative formulations by states such as California. Performance variations in fuel economy, emissions, and compatibility for these fuels have been evaluated and debated. In some cases contradictory views have surfaced. “Sustainable”, “Renewable”, and “Clean” designations have been interchanged. Adding to the confusion, results from one fuel in one type of engine such as an older heavy-duty engine, is at times compared to that of another type such as a modern light-duty. This study was an attempt to compare the performance of several fuels in an identical environment, using the same engine, for direct comparison.

Turbulent Jet Ignition is an advanced spark-initiated pre-chamber combustion system for an otherwise standard spark ignition engine found in current on-road vehicles. This next-generation pre-chamber design simply replaces the spark plug in a conventional spark ignition engine. Turbulent Jet Ignition enables very fast burn rates due to the ignition system producing multiple, widely distributed ignition sites, which consume the main charge rapidly. This high energy ignition system results from the partially combusted (reacting) pre-chamber products initiating main chamber combustion. The fast burn rates allow for increased levels of dilution (lean burn and/or EGR) when compared to conventional spark ignition combustion, with dilution levels being comparable to other low temperature combustion technologies (HCCI) without the complex control drawbacks.

Lean NOx Trap (LNT) catalysts can effectively reduce NOx from lean engine exhaust. Significant research for LNTs in diesel engine applications has been performed and has led to commercialization of the technology. For lean gasoline engine applications, advanced direct injection engines have led to a renewed interest in the potential for lean gasoline vehicles and, thereby, a renewed demand for lean NOx control. To understand the gasoline-based reductant chemistry during regeneration, a BMW lean gasoline vehicle has been studied on a chassis dynamometer. Exhaust samples were collected and analyzed for key reductant species such as H₂, CO, NH₃, and hydrocarbons during transient drive cycles. The relation of the reductant species to LNT performance will be discussed. Furthermore, the challenges of NOx storage in the lean gasoline application are reviewed.

The application of accelerated catalyst aging procedures on an engine dynamometer test bed for the purpose of demonstrating catalyst durability is examined. A proof-of-principle approach is followed using catalysts from vehicles certified to U.S. Tier 2 Bin 4 and California SULEV 2 levels. Accelerated durability demonstration methods based upon conventional fuel cut cycles were employed to age catalysts to levels predicted by quantification of thermal catalyst bed severity on the Standard Road Cycle (SRC) relative to the fuel cut aging cycle using the Bench Aging Time (BAT) equation. Emissions deterioration on the accelerated aging cycle is compared to the automobile manufacturers' certification values and to whole vehicle emissions performance results from several different in-use vehicle fleets. The influence of technology on whole vehicle emissions levels and deterioration characteristics is also evaluated.

Electric vehicle development is at a crossroads. Consumers want vehicles that offer the same size, performance, range, reliability and cost as their current vehicles. OEMs must make a profit, and the government requires compliance with emissions standards. The result - low volume, compromised vehicles that consumers don't want, with questionable longevity and minimal profitability. In-wheel motor technology offers a solution to these problems; providing power equivalent to ICE alternatives in a package that does not invade chassis, passenger and cargo space. At the same time in-wheel motors can reduce vehicle part count, complexity and cost, feature integrated power electronics, give complete design freedom and the potential for increased regenerative braking (reducing battery size and cost, or increasing range).

In recognizing the potential for large, damaging impacts from climate change, California enacted Executive Order S-03-05, requiring a reduction in statewide greenhouse gas (GHG) emissions to 80% below 1990 levels by 2050. Given that the transportation light-duty vehicle (LDV) segment accounts for 28% of the state's GHG emissions today, it will be difficult to meet the 2050 goal unless a portfolio of near-zero carbon transportation solutions is pursued. Because it takes decades for a new propulsion system to capture a large fraction of the passenger vehicle market due to vehicle fleet turn-over rates, it is important to accelerate the introduction of these alternatives to ensure markets enter into early commercial volumes (10,000s) between 2015 and 2020. This report summarizes the results and conclusions of a modeling exercise that simulated GHG emissions from the LDV sector to 2050 in California.

After the turn of the century, growing social attention has been paid to environmental concerns, especially the reduction of greenhouse gas emissions and it comes down to a personal daily life concern which will affect the purchasing decision of vehicles in the future. Among all the sources of greenhouse gas emissions, the transportation industry is the primary target of reduction and almost every automotive company pours unprecedented amounts of money to reengineer the vehicle technologies for better fuel efficiency and reduced CO2 emission. Besides those efforts paid for sheer improvements of genuine vehicle technologies, NISSAN testified that “connectivity” with outside servers contributed a lot to reduce fuel consumption, thus the less emission of GHG, with two major factors; 1. detouring the traffic congestions with the support of probe-based real-time traffic information and 2. providing Eco-driving advices for the better driving behavior to prompt the better usage of energy.

For a series plug-in hybrid electric vehicle (PHEV), it is critical that batteries be sized to maximize vehicle performance variables, such as fuel efficiency, gasoline savings, and zero emission capability. The wide range of design choices and the cost of prototype vehicles calls for a development process to quickly and systematically determine the design characteristics of the battery pack, including its size, and vehicle-level control parameters that maximize the net present value (NPV) of a vehicle during the planning stage. Argonne National Laboratory has developed Autonomie, a modeling and simulation framework. With support from The MathWorks, Argonne has integrated an optimization algorithm and parallel computing tools to enable the aforementioned development process. This paper presents a study that utilized the development process, where the NPV is the present value of all the future expenses and savings associated with the vehicle.

In 2005, the growing emphasis on fuel efficiency coupled with the long-recognized negative effects of viscous friction caused by engine hydrodynamic lubrication, led to considerations of the benefits of lower viscosity engine oils by the SAE Engine Oil Viscosity Classification (EOVC) Task Force. More recently these considerations were given further impetus by OEM enquiry regarding modification of the SAE Viscosity Classification System to include oils of lower viscosity specification than that of SAE 20. For the EOVC Task Force, such considerations of commercially available, significantly lower viscosity engine oils, also produced a need to reassess the precision of high shear rate viscometry of such engine oils as presently practiced at 150°C - as well as interest in temperatures such as 100° and 120°C believed more representative of engine operating conditions.

Today's automotive and electronics technologies are evolving so rapidly that educators and industry are both challenged to re-educate the technological workforce in the new area before they are replaced with yet another generation. In early November 2009 Ford's Product Development senior management formally approved a proposal by the University of Detroit Mercy to transform 125 of Ford's “IC Engine Automotive Engineers” into “Advanced Electric Vehicle Automotive Engineers.” Two months later, the first course of the Advanced Electric Vehicle Program began in Dearborn. UDM's response to Ford's needs (and those of other OEM's and suppliers) was not only at the rate of “academic light speed,” but it involved direct collaboration of Ford's electric vehicle leaders and subject matter experts and the UDM AEV Program faculty.

This paper discusses the fundamentals of architecting a major human spaceflight program and some of the lessons that can be learned from NASA's Constellation Program. This paper describes the Constellation program, whose primary objective focuses on development of a new generation of vehicles and systems to enable human exploration beyond Earth orbit. Constellation is made up of seven projects that are highly interdependent and is referred to in the NASA management system as a “tightly coupled” program. This paper will discuss the driving architectural priorities and characteristics for human exploration missions beyond earth orbit and how its building blocks are developed through initial capability missions to the International Space Station. The systems engineering challenges of simultaneously defining and developing systems that are interdependent will be discussed.

FlexRay is a time triggered automotive communication protocol that connects ECUs (Electronic Control Units) on which distributed automotive applications are executed. If exact agreement (e.g. on physical values measured by redundant sensors on different ECUs) must be reached in the presence of asymmetric communication faults, a byzantine agreement protocol like Signed Messages (SM) can be utilized. This paper gives examples of how byzantine faults can emerge in a FlexRay-based system and proposes optimizations for a FlexRay-specific implementation of the SM protocol. The protocol modifications allow for a reduction in the number of protocol messages under a slightly relaxed fault model, as well as for a reduction in the number of messages to be temporarily stored by the ECUs.

Driver distraction is a topic of considerable interest, with the public debate centering on the use of cell phones and texting while driving. However, the driver distraction/overload issue is really much larger. It concerns specific tasks such as entering destinations on navigation systems, retrieving songs on MP3 players, accessing web pages, checking stocks, editing spreadsheets, and performing other tasks on smart phones, as well as, more generally, using in-vehicle information systems. Five major problems related to distraction/overload research and engineering and their solutions are addressed in this paper.

A brief explanation of the design iterations and philosophy used to integrate the pilot into the F-35 Lightning II cockpit to achieve optimum Pilot Vehicle Interface (PVI), manageable single seat workload, and superior situation awareness.

The recent interest in IntelliDrive(SM) and vehicle connectivity has gone past previous notions of automatic collision notification, internet browsing and off board navigation. Now, in addition to applying the 5.9 GHz ITS band for cooperative collision avoidance, other applications using connectivity between the vehicle and signalized intersections have emerged. Contemporary applications enhancing fuel economy and reducing green house gases (GHG) are the subject of current research and development. Cooperation between vehicle electronics and intelligent traffic management systems could change the landscape for addressing future ECO (economical and ecological) requirements. This manuscript will outline development within one automotive supplier targeted at using connectivity as an enabling technology for sustaining the vision of smart and green transportation systems.

Electrification of the automobile is a growing trend and will create both challenges and opportunities for the vehicle manufacturer, road network infrastructure and driver. In addition to innovative fundamental battery and power transfer technologies, electric vehicles will integrate unique driver interfaces, road intelligence, traffic awareness and wireless data communication to provide a complete support system. This networked vehicle will improve efficiency, increase cruising range and contribute to the overall driving enjoyment of an electric or plug-in hybrid-electric vehicle. Through tailored applications created by content and service providers the driver will identify the most efficient travel routes, learn efficient driving behaviors, avoid energy-wasting situations, locate charging stations and have confidence in reaching a destination and returning home.