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Technical Paper

A Research Design to Collect Data for a Second Generation Eyellipse

Current automotive design practices related to driver visibility are based on static laboratory studies of mostly straight ahead viewing that were conducted by Meldrum and others beginning in 1962. These individual studies have never been replicated either in the lab or in actual driving situations to determine the validity of their procedures. After a thorough review of the literature related to driver eye location and a statistical analysis of previous static eye location data, an experimental design is proposed to determine dynamic eye location distribution characteristics. This design will provide information on: (a) the relationship of static anthropometric measurements to dynamic eye location; (b) the difference between dynamic on-the-road eye location versus static in-the-lab eye location distributions: (c) the effect of different types of vehicle seating package parameters on eye location; and, (d) a validation of previous static eye location studies.
Technical Paper

A Survey of Alcohol as a Motor Fuel

Alcohol has been promoted and used as a motor fuel for more than 50 years. However, United States ethyl alcohol production is small compared with gasoline production. High latent heat of vaporization of alcohol makes possible some increase of power over gasoline. The heating value of alcohol is low and energy content of alcohol blends is less than that of gasoline; fuel consumption of blends is therefore increased. The ability of ethanol to improve the octane number of gasoline has diminished as the octane number of gasoline has improved. There is no published evidence that alcohols can appreciably reduce air pollution problems.
Technical Paper

Absorption and Fluorescence Data of Acetone, 3-Pentanone, Biacetyl, and Toluene at Engine-Specific Combinations of Temperature and Pressure

Quantitative planar laser-induced fluorescence measurements of fuel/air mixing in engines are usually based on the use of fluorescence tracers. The strength of the signals often depends on temperature, pressure and mixture composition. This complicates a quantitative analysis. The use of a small-bore optical engine for fundamental studies of absorption and fluorescence properties of fluorescence tracers is described. The temperature, pressure and composition dependence of the spectra of toluene, acetone, 3-pentanone, and biacetyl are examined under motored conditions to extend the experimental data base for the development of comprehensive models that predict the strength of fluorescence signals for a given condition.
Technical Paper

Algorithmic Maintenance of a Diesel Engine Electronic Fuel Feed Controller by Criterion of the Content of Soot in Exhaust Gas

The feature of offered algorithm is that it allows, without record and analysis of the display diagram, to estimate a running cycle of a diesel engine parameters which characterize ecological and economic performances. The mathematical model described in report allows to determine connection of coefficient of filling, pressure and temperature of air boost, factor of excess of air with effectiveness ratio of combustion and contents of soot in exhaust gas and to take into account this connection at a choice initial data for control fuel feed or for elaboration of diesel engine dynamic model. The algorithm incorporated, for example, in the microcontroller of an electronic fuel feed controller allows analyzing the sensors data and theoretically determine of smoke amount in the exhaust gases for chosen cycle of fuel feed. The restriction of smoke is possible by criterion dD/dGT, where D - contents of soot in exhaust gas and GT - fuel cycle submission under the program-adaptive schema.
Technical Paper

An Investigation of Catalytic Converter Performances during Cold Starts

Automotive exhaust emission regulations are becoming progressively stricter due to increasing awareness of the hazardous effects of exhaust emissions. The main challenge to meet the regulations is to reduce the emissions during cold starts, because catalytic converters are ineffective until they reach a light-off temperature. It has been found that 50% to 80% of the regulated hydrocarbon and carbon monoxide emissions are emitted from the automotive tailpipe during the cold starts. Therefore, understanding the catalytic converter characteristics during the cold starts is important for the improvement of the cold start performances This paper describes a mathematical model that simulates transient performances of catalytic converters. The model considers the effect of heat transfer and catalyst chemical reactions as exhaust gases flow through the catalyst. The heat transfer model includes the heat loss by conduction and convection.
Technical Paper

Anatomy and Physiology of the Respiratory System

The anatomy of the human respiratory system is detailed. The function of the entire system is shown from inspiration to expiration. Equations are given to illustrate flow-pressure relationships in the airways. Specifics of gas transfer are shown. All these details of physiology and function are necessary for an understanding of the effects of air pollution upon the human respiratory system.
Technical Paper

Assessing the Fuel Economy Potential of Light-Duty Vehicles

This paper assesses the potential for car and light truck fuel economy improvements by 2010-15. We examine a range of refinements to body systems and powertrain, reflecting current best practice as well as emerging technologies such as advanced engine and transmission, lightweight materials, integrated starter-generators, and hybrid drive. Engine options are restricted to those already known to meet upcoming California emissions standards. Our approach is to apply a state-of-art vehicle system simulation model to assess vehicle fuel economy gains and performance levels. We select a set of baseline vehicles representing five major classes - Small and Standard Cars, Pickup Trucks, SUVs and Minivans - and analyze design changes likely to be commercially viable within the coming decade. Results vary by vehicle type.
Technical Paper

Assessment of Alternative Strategies for Reducing Hydrocarbon and Carbon Monoxide Emissions from Small Two-Stroke Engines

Five small two-stroke engine designs were tested at different air/fuel ratios, under steady state and transient cycles. The effects of combustion chamber design, carburetor design, lean burning, and fuel composition on performance, hydrocarbon and carbon monoxide emissions were studied. All tested engines had been designed to run richer than stoichiometric in order to obtain satisfactory cooling and higher power. While hydrocarbon and carbon monoxide emissions could be greatly reduced with lean burning, engine durability would be worsened. However, it was shown that the use of a catalytic converter with acceptably lean combustion was an effective method of reducing emissions. Replacing carburetion with in-cylinder fuel injection in one of the engines resulted in a significant reduction of hydrocarbon and carbon monoxide emissions.
Technical Paper

Automobile Demand and the Policy Forecast

Mathematical models of the automotive system play a valuable role in forecasting and policy analysis, especially in the public sector. However, poor documentation, lack of adequate model evaluation and unfamiliarity with the data and structural limitations of models suggest the possibility of misuse in such policy applications as fuel economy standards and regulatory impact assessments. Findings are illustrated by analysis of two models: the Wharton EFA Automobile Demand Model and the Sweeney Passenger Car Gasoline Demand Model. In addition, 40 world sector models and studies representing more than 75 countries are summarized.
Technical Paper

Automotive Air Conditioning Systems with Absorption Refrigeration

An automotive absorption air conditioning system would use engine-rejected heat as its energy source. Three possible cycles were studied, based on using water-lithium bromide, ammonia-water, and refrigerant 22-dimethyl ether of tetraethylene glycol as the refrigerant-absorbent pairs. Heat balances were calculated for the cycles and for a comparable vapor compression cycle. Energy input requirements, cooling capacities, coefficients of performance, and pressures and temperatures at various points in the cycle are given. Energy input requirements are compared with test data on the heat rejection from a 390 cu in. displacement production engine.
Technical Paper

Basic Physiology of Carbon Monoxide

The physiology of carbon monoxide is discussed in the human respiratory system. The details of the relationship of carbon monoxide and hemoglobin are outlined, and the effects of specific concentrations of CO are shown. Acute and chronic exposures to CO create certain effects on the various bodily systems, and these are described in detail.
Technical Paper

Cam-phasing Optimization Using Artificial Neural Networks as Surrogate Models-Fuel Consumption and NOx Emissions

Cam-phasing is increasingly considered as a feasible Variable Valve Timing (VVT) technology for production engines. Additional independent control variables in a dual-independent VVT engine increase the complexity of the system, and achieving its full benefit depends critically on devising an optimum control strategy. A traditional approach relying on hardware experiments to generate set-point maps for all independent control variables leads to an exponential increase in the number of required tests and prohibitive cost. Instead, this work formulates the task of defining actuator set-points as an optimization problem. In our previous study, an optimization framework was developed and demonstrated with the objective of maximizing torque at full load. This study extends the technique and uses the optimization framework to minimize fuel consumption of a VVT engine at part load.
Technical Paper

Comparison of Diesel Oxidation Catalyst Performance on an Engine and a Gas Flow Reactor

This paper analyzes and compares reactor and engine behavior of a diesel oxidation catalyst (DOC) in the presence of conventional diesel exhaust and low temperature premixed compression ignition (PCI) diesel exhaust. Surrogate exhaust mixtures of n-undecane (C11H24), ethene (C2H4), CO, O2, H2O, NO and N2 are defined for conventional and PCI combustion and used in the gas flow reactor tests. Both engine and reactor tests use a DOC containing platinum, palladium and a hydrocarbon storage component (zeolite). On both the engine and reactor, the composition of PCI exhaust increases light-off temperature relative to conventional combustion. However, while nominal conditions are similar, the catalyst behaves differently on the two experimental setups. The engine DOC shows higher initial apparent HC conversion efficiencies because the engine exhaust contains a higher fraction of trappable (i.e., high boiling point) HC.
Technical Paper

Correlation of Spray Cone Angle and Fuel Line Pressure in a Pressure-Swirl Injector Spray

The transient cone angle of a pressure swirl spray from an injector for gasoline direct injection engines was measured from 2D Mie scattering images. Iso-octane was used as the fluid that was delivered at room temperature for two different static pressures, 5MPa and 8.5MPa. The iso-octane was injected into a chamber at room temperature and ambient pressure. After a rapid initial increase, the cone angle oscillates before stabilizing to a steady-state value very close to the nominal cone angle. The period of the oscillation was found to correlate well with oscillations measured in the fuel line pressure.
Technical Paper

Driving with HID Headlamps: A Review of Research Findings

High-intensity discharge (HID) headlamps have several advantages over tungsten-halogen headlamps, including greater light efficiency (lumens per watt) and longer life. However, from the safety point of view, the primary attraction of HID headlamps is that, because they produce more total light, they have the potential to provide more useful illumination to the driver. At the same time, there are concerns with the effects of HID illumination on perception of the colors of important objects and glare to oncoming traffic. This paper reviews research evidence that we have accumulated over the past 14 years concerning the potential benefits and drawbacks associated with the use of HID headlighting. We conclude that the evidence strongly supports the use of well-designed HID headlamps.
Technical Paper

Experimental Investigation of Plasticized Polyvinylchloride using the Split Hopkinson Pressure Bar Technique

Characterization of materials used in the automotive industry is often done via component testing. A strict regimen of tests is conducted on a component to determine material parameters for numerical simulations of more complicated loading conditions. Separation of material constants and geometrically- or experimentallyinduced effects is difficult with this method of characterization. Well-controlled experiments that determine the material response in basic deformations allow material properties to be determined. In this paper low strain rate and high strain rate experimental responses of dummy skin material (i.e. plasticized polyvinyl chloride) are presented. Details of the experimental procedures used to acquire the data are also included. In addition, a rate-dependent constitutive model for the plasticized material is developed, and its simulated results are compared with low strain rate results.
Technical Paper

Factors Influencing Spark Behavior in a Spray-Guided Direct-Injected Engine

The spark process has previously been shown to heavily influence ignition stability, particularly in direct-injected gasoline engines. Despite this influence, few studies have addressed spark behavior in direct-injected engines. This study examines the role of environmental factors on the behavior of the spark. Through measurement of the spark duration, by way of the ignition current trace, several observations are made on the influence of external factors on the behavior of the spark. Changing the level of nitrogen in the cylinder (to simulate EGR), the level of wetting and velocity imparted by the spray, the ignition dwell time and the orientation of the ground strap, observations are made as to which conditions are likely to produce unfavorable (shorter) spark durations. Through collection of a statistically significant number of sample spark lengths under each condition, histograms have been assembled and compared under each case.
Technical Paper

Failure Mechanisms of Sandwich Specimens With Epoxy Foam Cores Under Bending Conditions

Sandwich specimens with DP590 steel face sheets and structural epoxy foam cores are investigated under three-point bending conditions. Experimental results indicate that the maximum loads correspond to extensive cracking in the foam cores. Finite element simulations of the bending tests are also performed to understand the failure mechanisms of the epoxy foams. In these simulations, the plastic behavior of the steel face sheets is modeled by the Mises yield criterion with consideration of plastic strain hardening. A pressure sensitive yield criterion is used to model the plastic behavior of the epoxy foam cores. The epoxy foams are idealized to follow an elastic perfectly plastic behavior. The simulation results indicate that the load-displacement responses of some sandwich specimens agree with the experimental results.
Technical Paper

Health Aspects of Atmospheric Exposure to Lead

The paper discusses how atmospheric exposure to lead affects health. Sources of lead in the atmosphere are explored, lead aerosol is described, and the importance of lead in the diet is discussed. Methods of detecting lead in the human system are detailed. The paper suggests that a threshold limit of atmospheric lead be firmly established.
Technical Paper

Hydrocarbon Emission Sequence Related to Cylinder Mal-Distribution in a L-Head Engine

The distribution of fuel-air mixtures in many L-head engines is not homogeneous. If local mixture is too rich or lean, incomplete combustion occurs. This can play a major role in unburned hydrocarbon and carbon monoxide emissions. Fuel-air mixture distribution depends on in-cylinder swirl and turbulence and is directly related to intake manifold configuration, fuel delivery system design and combustion chamber shape. Understanding the spatial mixture distribution may help improve the design of these aforementioned components. Consequently, a more complete combustion process may result, and emissions reduced. A method that measures the emission of CH and C2 radicals via the use of an optical fiber bundle was used in this research to map the mixture uniformity in the combustion chamber. The intensity ratio (IC2/ICH) was correlated to the fuel-air equivalence ratio. The mixture distribution measured was then correlated with the hydrocarbon emission sequence.