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1. On page 111, the authors have described a method to assess driver distraction. In this method, participants maintained a white square size on a forward display by using a game gas pedal of like in car-following situation. The size of the white square is determined by calculating the distance to a virtual lead vehicle. The formulas to correct are used to explain variation of acceleration of the virtual lead vehicle. The authors inadvertently incorporated old formulas they had used previously. In the experiments discussed in the article, the corrected formulas were used. Therefore, there is no change in the results. The following from the article:

This paper presents a review on pedestrian impact reconstruction methodology and offers a comprehensive review of the literature. Several types of analyses are discussed which can be used to reconstruct the accident scenario using the facts collected from the scene. Inclusive in this review is the utilization of skid mark analysis, debris analysis, injury/damage match-up, trajectory analysis, nighttime visibility, and alcohol effects. The pedestrian impact reconstruction methodology is illustrated with a real world case example to point out different observations which can provide insight into the pedestrian/vehicle collision reconstruction approach. The literature review provides a broad foundation of information on pedestrian impact reconstruction and can be used to supplement the techniques presented in this paper in areas related to pedestrian impact. Research advances in the area of pedestrian impact reconstruction are also discussed in this paper.

A literature review was conducted to survey recent research on the effects of fuel properties on exhaust emissions from gasoline and diesel vehicles, on-road and off-road. Most of the literature has been published in SAE papers, although data have also been reported in other journals and government reports. A full report and database are available from the Coordinating Research Council (www.crcao.org). The review identified areas of agreement and disagreement in the literature and evaluated the adequacy of experimental design and analysis of results. Areas where additional research would be helpful in defining fuel effects are also identified. In many of the research programs carried out to evaluate the effect of new blendstocks, the fuel components were splash blended in fully formulated fuels. This approach makes it extremely difficult to determine the exact cause of the emissions benefit or debit.

The goal of this research is to investigate the physical parameters of stoichiometric operation of a diesel engine under a light load operating condition (6∼7 bar IMEP). This paper focuses on improving the fuel efficiency of stoichiometric operation, for which a fuel consumption penalty relative to standard diesel combustion was found to be 7% from a previous study. The objective is to keep NOx and soot emissions at reasonable levels such that a 3-way catalyst and DPF can be used in an aftertreatment combination to meet 2010 emissions regulation. The effects of intake conditions and the use of group-hole injector nozzles (GHN) on fuel consumption of stoichiometric diesel operation were investigated. Throttled intake conditions exhibited about a 30% fuel penalty compared to the best fuel economy case of high boost/EGR intake conditions. The higher CO emissions of throttled intake cases lead to the poor fuel economy.

How can car designers evaluate device’s position inside a car today? Today only subjective tests or “reachability” tests are made to assess if a generic user is able to reach devices, but it’s no longer enough. The aim of this study is to identify an instrument (index) that is able to provide a numerical information about the discomfort level connected with a posture that is kept inside a car to reach a device, by this instrument it should be possible not only judge a posture, but also compare different solutions and get rapid and accurate evaluations. In the state of the art there are many indexes developed to evaluate postural comfort (like RULA, REBA and LUBA [3, 4, 5]) but none of them has been realized to evaluate postures’ conditions that can be detected inside a car, so their evaluations cannot be acceptable.

A realistic modeling of the wall heat transfer is essential for an accurate analysis and simulation of the working cycle of internal combustion engines. Empirical heat transfer formulations still dominate the application in engine process simulations because of their simplicity. However, experiments have shown that existing correlations do not provide satisfactory results for all the possible operation modes of hydrogen internal combustion engines. This paper describes the application of a flow field-based heat transfer model according to Schubert et al. [1]. The models strength is a more realistic description of the required characteristic velocity; considering the influence of the injection on the global turbulence and on the in-cylinder flow field results in a better prediction of the wall heat transfer during the compression stroke and for operations with multiple injections. Further an empirical hypothesis on the turbulence generation during combustion is presented.

LCDs are effective to display abundant information in a compact space. Therefore, the use of TFT or DOT metric displays in dashboard instrument display is getting popular in recent years. However, it is important issue for car makers how to let users know information about vehicle functions or outside environment and manage plentiful information. In this paper, the Rapid Control Prototyping (RCP) tool is proposed to design and standardize HMI logic associated with display contents in TFT or dot type LCD applied to an instrument cluster. In addition, it is possible to estimate HMI logic in advance by using this RCP. By this process, we can minimize the design and validation time of the vehicle specific HMI logic and improve the quality. As a result, we can dramatically reduce the total period of developing an instrument cluster.

Because niobium-clad 304L stainless steel sheets are considered for use as bipolar plates in polymer electrolyte membrane (PEM) fuel cells, their mechanical behavior and failure mechanism are important to be examined. As-rolled and annealed specimens were tested in tension, bending and flattening. The effects of annealing temperature and time on the mechanical behavior and failure mechanism were investigated. Micrographic analyses of bent and flattened specimens showed that the as-rolled specimens have limited ductility and that the annealed specimens can develop an intermetallic layer of thickness of a few microns. The annealed specimens failed due to the breakage of intermetallic layer causing localized necking and the subsequent failure of Nb layer. The springback angles of the as-rolled and annealed specimens were also obtained from guided-bend tests.

Ford Motor Company is introducing “EcoBoost” gasoline turbocharged direct injection (GTDI) engine technology in the 2010 Lincoln MKS. A logical enhancement of EcoBoost technology is the use of E85 for knock mitigation. The subject of this paper is the optimal use of E85 by using two fuel systems in the same EcoBoost engine: port fuel injection (PFI) of gasoline and direct injection (DI) of E85. Gasoline PFI is used for starting and light-medium load operation, while E85 DI is used only as required during high load operation to avoid knock. Direct injection of E85 (a commercially available blend of ∼85% ethanol and ∼15% gasoline) is extremely effective in suppressing knock, due to ethanol's high inherent octane and its high heat of vaporization, which results in substantial cooling of the charge. As a result, the compression ratio (CR) can be increased and higher boost levels can be used.

The internal combustion engine and associated powertrain are likely to remain the mainstay of mobility over the next twenty years and to remain a significant portion of the portfolio of technologies employed over a much longer period of time. Efficient combustion of all fuels (petroleum based or alternative) requires copious amounts of air particularly with downsized engines. Turbocharging technology thus becomes an even more critical part of reducing both global warming gas and urban pollutant emissions from IC engines. Gasoline engine downsizing and turbocharging have been shown to improve fuel economy by ∼20% in production vehicles. In addition to data over a wide range of engines/vehicles, the results of a simple analysis done on vehicles/engines/drive cycles are presented to show the benefits of turbocharging and downsizing in a parametric variation of downsizing in combination with other technologies.

In order to detect degradation of engine oil lubricant, bench testing along with a number of diesel-powered Ford trucks were instruments and tested. The purpose of the bench testing was primarily to determine performance aspects such as repeatability, hysteresis effects and so on. Vehicle testing was conducted by designing and installing a separate oil reservoir along with a circulation system which was mounted in the vicinity of the oil pan. An innovative oil sensor was directly installed on the reservoir which can measure five (5) independent oil parameters (viscosity, density, permittivity, conductance, temperature). In addition, the concept is capable of detecting the oil level continuously during normal engine operation. The sensing system consists of an ultrasonic transducer for the oil level detection as well as a Tuning Fork mechanical resonator for the oil condition measurement.

The Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model incorporated fuel economy and electricity use of alternative fuel/vehicle systems simulated by the Powertrain System Analysis Toolkit (PSAT) to conduct a well-to-wheels (WTW) analysis of energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). Based on PSAT simulations of the blended charge depleting (CD) operation, grid electricity accounted for a share of the vehicle’s total energy use ranging from 6% for PHEV 10 to 24% for PHEV 40 based on CD vehicle mile traveled (VMT) shares of 23% and 63%, respectively. Besides fuel economy of PHEVs and type of on-board fuel, the type of electricity generation mix impacted the WTW results of PHEVs, especially GHG emissions.

Diesel injection parameters effect on liquid-phase diesel spray penetration after the end-of-injection (EOI) is investigated in a constant-volume chamber over a range of ambient and injector conditions typical of a diesel engine. Our past work showed that the maximum liquid penetration length of a diesel spray may recede towards the injector after EOI at some conditions. Analysis employing a transient jet entrainment model showed that increased fuel-ambient mixing occurs during the fuel-injection-rate ramp-down as increased ambient-entrainment rates progress downstream (i.e. the entrainment wave), permitting complete fuel vaporization at distances closer to the injector than the quasi-steady liquid length. To clarify the liquid-length recession process, in this study we report Mie-scatter imaging results near EOI over a range of injection pressure, nozzle size, fuel type, and rate-of-injection shape. We then use a transient jet entrainment model for detailed analysis.

The local equivalence ratio, Φ, was measured in fuel jets using laser-induced spontaneous Raman scattering in an optical heavy duty diesel engine. The measurements were performed at 1200 rpm and quarter load (6 bar IMEP). The objective was to study factors influencing soot formation, such as gas entrainment and lift-off position, and to find correlations with engine-out particulate matter (PM) levels. The effects of nozzle hole size, injection pressure, inlet oxygen concentration, and ambient density at TDC were studied. The position of the lift–off region was determined from OH chemiluminescence images of the flame. The liquid penetration length was measured with Mie scattering to ensure that the Raman measurement was performed in the gaseous part of the spray. The local Φ value was successfully measured inside a fuel jet. A surprisingly low correlation coefficient between engine-out PM and the local Φ in the reaction zone were observed.

Recent measurements in transient diesel jets have shown that fuel in the wake of the injection pulse mixes with ambient gases more rapidly than in a steady jet. This rapid mixing after the end of injection (EOI) can create fuel-lean regions near the fuel injector. These lean regions may not burn to completion for conditions where autoignition occurs after EOI, as is typical of low-temperature combustion (LTC) diesel engines. In this study, transient diesel jets are analyzed using a simple one-dimensional jet model. The model predicts that after EOI, a region of increased entrainment, termed the “entrainment wave,” travels downstream at twice the initial jet propagation rate. The entrainment wave increases mixing by up to a factor of three. This entrainment wave is not specific to LTC jets, but rather it is important for both conventional diesel combustion and LTC conditions.

Automotive engines are regularly utilized in the material handling market where LPG is often the primary fuel used. When compared to gasoline, the use of gaseous fuels (LPG and CNG) as well as alcohol based fuels, often result in significant increases in valve seat insert (VSI) and valve face wear. This phenomenon is widely recognized and the engine manufacturer is tasked to identify and incorporate appropriate valvetrain material and design features that can meet the ever increasing life expectations of the end-user. Alternate materials are often developed based on laboratory testing – testing that may not represent real world usage. The ultimate goal of the product engineer is to utilize accelerated lab test procedures that can be correlated to field life and field failure mechanisms, and then select appropriate materials/design features that meet the targeted life requirements.

In this work a detailed model to simulate the transient behavior of catalytic converters is presented. The model is able to predict the unsteady and reacting flows in the exhaust ducts, by solving the system of conservation equations of mass, momentum, energy and transport of reacting chemical species. The en-gine and the intake system have not been included in the simulation, imposing the measured values of mass flow, gas temperature and chemical composition as a boundary condition at the inlet of the exhaust system. A detailed analysis of the diffusion stage triggering is proposed along with simplifications of the physics, finalized to the reduction of the calculation time. Submodels for water condensation and its following evaporation on the monolith surface have been taken into account as well as oxygen storage promoted by ceria oxides.

A thorough understanding of vehicle exhaust aftertreatment system performance requires time-resolved emissions measurements that accurately follow driving transients, and that are correctly time-aligned with exhaust temperature and flow measurements. The transient response of conventional gas analyzers is characterized by both a time delay and an attenuation of high-frequency signal components. The distortion that this imposes on transient emissions measurements causes significant errors in instantaneous calculations of aftertreatment system efficiency, and thus in modal mass analysis. This creates difficulties in mathematical modeling of emissions system performance and in optimization of powertrain control strategies, leading to suboptimal aftertreatment system designs. A mathematical method is presented which improves the response time of emissions measurements. This begins with development of a model of gas transport and mixing within the sampling and measurement system.

The challenges of flex-fuel vehicle (FFV) emissions measurements have recently come to the forefront for the emissions testing community. The proliferation of ethanol blended gasoline in fractions as high as 85% has placed a new challenge in the path of accurate measures of NMHC and NMOG emissions. Test methods need modification to cope with excess amounts of water in the exhaust, assure transfer and capture of oxygenated compounds to integrated measurement systems (impinger and cartridge measurements) and provide modal emission rates of oxygenated species. Current test methods fall short of addressing these challenges. This presentation will discuss the challenges to FFV testing, modifications made to Ford Motor Company’s Vehicle Emissions Research Laboratory test cells, and demonstrate the improvements in recovery of oxygenated species from the vehicle exhaust system for both regulatory measurements and development measurements.

Quantitative planar laser-induced fluorescence (PLIF) of gaseous acetone as a fuel-tracer has been used in an optically accessible engine, fueled by direct hydrogen injection. The purpose of this article is to assess the accuracy and precision of the measurement and the associated data reduction procedures. A detailed description of the acetone seeding system is given as well. The key features of the experiment are a high-pressure bubbler saturating the hydrogen fuel with acetone vapor, direct injection into an optical engine, excitation of acetone fluorescence with an Nd:YAG laser at 266 nm, and detection of the resulting fluorescence by an unintensified camera. Key steps in the quantification of the single-shot imaging data are an in-situ calibration and a correction for the effect of local temperature on the fluorescence measurement.