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Combustion flame geometry calculation is a critical task in the design and analysis of combustion engine chamber. Combustion flame directly influences the fuel economy, engine performance and efficiency. Currently, many of the flame geometry calculation methods assume certain specific chamber and piston top shapes and make some approximations to them. Even further, most methods can not handle multiple spark plug set-ups. Consequently, most of the current flame geometry calculation methods do not give accurate results and have some built-in limitations. They are particularly poor for adapting to any kind of new chamber geometry and spark plug set-up design. This report presents a novel methodology which allows the accurate calculation of flame geometry regardless of the chamber geometry and the number of spark plugs. In this methodology, solid models are used to represent the components within the chamber and unique attributes (colors) are attached respectively to these components.

Ignition stability was studied in an optical spray guided spark ignition direct injection engine. The impact of intake air dilution with nitrogen, spark plug orientation, ignition system dwell time, and fuel injector targeting was addressed. Crank angle resolved fuel distributions were measured with a high-speed planar laser-induced fluorescence technique for hundreds of consecutive cycles. IMEP, COV of IMEP, burn rates and spark energy delivered to the gas were examined and used in conjunction with the imaging data to identify potential reasons for misfires.

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.

In this paper, the available correlations proposed in the literature for the gas-side heat transfer in the intake and exhaust system of a spark-ignition internal combustion engine were surveyed. It was noticed that these only by empirically fitted constants. This similarity provided the impetus for the authors to explore if a universal correlation could be developed. Based on a scaling approach using microscales of turbulence, the authors have fixed the exponential factor on the Reynolds number and thus reduced the number of adjustable coefficients to just one; the latter can be determined from a least squares curve-fit of available experimental data. Using intake and exhaust side data, it was shown that the universal correlation The correlation coefficient of this proposed heat transfer model with all available experimental data is 0.845 for the intake side and 0.800 for the exhaust side.

A formulation that accounts for manufacturing variability in the analysis of structural/acoustic systems is presented. The methodology incorporates the concept of fast probability integration with finite element (FEA) and boundary element analysis (BEA) for producing the probabilistic acoustic response of a structural/acoustic system. The advanced mean value method is used for integrating the system probability density function. FEA and BEA are combined for producing the acoustic response that constitutes the performance function. The probabilistic acoustic response is calculated in terms of a cumulative distribution function. The new methodology is used to illustrate the difference between the results from a probabilistic analysis that accounts for manufacturing uncertainty, and an equivalent deterministic simulation through applications. The probabilistic computations are validated by comparison to Monte Carlo simulations.

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.

The greatest demand facing the automotive industry has been to provide safer vehicles with high fuel efficiency at minimum cost. Current automotive vehicle structures have one fundamental handicap: a short crumple zone for crash energy absorption. This leaves limited room for further safety improvement, especially for high-speed crashes. Breakthrough technologies are needed. One potential breakthrough is to use active devices instead of conventional passive devices. An innovative inflatable bumper concept [1], called the “I-bumper,” is being developed by the authors for crashworthiness and safety of military and commercial vehicles. The proposed I-bumper has several active structural components, including a morphing mechanism, a movable bumper, two explosive airbags, and a morphing lattice structure with a locking mechanism that provides desired rigidity and energy absorption capability during a vehicular crash.

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.

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.

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.

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.

The spatial and temporal formation of nitric oxide in an optical engine operated with iso-octane fuel under spray-guided direct-injection conditions was studied with a combination of laser-induced fluorescence imaging, UV-chemiluminescence, and cycle resolved NO exhaust gas analysis. NO formation during early and late (homogeneous vs. stratified) injection conditions were compared. Strong spatial preferences and cyclic variations in the NO formation were observed depending on engine operating conditions. While engine-out NO levels are substantially lower for stratified engine operation, cyclic variations of NO formation are substantially higher than for homogeneous, stoichiometric operation.

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.

This paper presents a general control module to control the speed of an electric vehicle (EV). This module consists of a microprocessor and several C-programmable micro-controllers. It uses an identification algorithm to estimate the system parameters on-line. With the estimated parameters, control gains are calculated via pole-placement. In order to compensate for the internal errors, a cross-coupling control algorithm is included. To estimate the true velocity and acceleration from measurements, a discrete-time Kalman filter was utilized. The experimental results validate the general control module for EVs.

A combination of imaging techniques for investigations of highly transient processes and cyclic variations in internal combustion engines is presented. The single high-speed camera setup uses a CMOS camera combined with a two-stage image-intensifier and two excimer lasers. Fuel mixing, ignition and combustion were monitored via planar laser induced fluorescence imaging of toluene as a tracer that was added to iso-octane in combination with the simultaneous recording of light emission from the spark plasma and OH* chemiluminescence of the developing flame. Image frame rates of 12 kHz for hundreds of cycles were achieved. Application to misfire events in a spray-guided gasoline direct-injection engine is described to illustrate the merits of the technique.

A potential correlation between OH* chemiluminescence and exhaust NO concentration is investigated to pursue a simple diagnostic technique for measurements of NO cycle-to-cycle fluctuations. Previous investigations of NO formation in a direct-injection gasoline engine have indicated that there may be a correlation between the concentration of NO and OH* chemiluminescence. Shortcomings of this work, namely phase-locked measurements, were overcome in the present study by using highspeed imaging capability to obtain chemiluminescence within the entire engine cycle and from entire engine cylinder volume. Cycle-resolved NO exhaust gas detection were performed synchronously with the chemiluminescence measurements on an optical spark-ignited engine with spray-guided direct-injection. A quartz cylinder liner, head and piston windows provide optical access for a highspeed CMOS camera and image intensifier to capture OH* images.

A summary of the design and development process for a Formula SAE engine is described. The focus is on three fundamental elements on which the entire engine package is based. The first is engine layout and displacement, second is the fuel type, and third is the air induction method. These decisions lead to a design around a 4-cylinder 600cc motorcycle engine, utilizing a turbocharger and ethanol E-85 fuel. Concerns and constraints involved with vehicle integration are also highlighted. The final design was then tested on an engine dynamometer, and finally in the 2007 M-Racing FSAE racecar.

A regenerative braking model for a parallel Hybrid Electric Vehicle (HEV) is developed in this work. This model computes the line and pad pressures for the front and rear brakes, the amount of generator use depending on the state of deceleration (i.e. the brake pedal position), and includes a wheel lock-up avoidance algorithm. The regenerative braking model has been developed in the symbolic programming environment of MATLAB/SIMULINK/STATEFLOW for downloadability to an actual HEV's control system. The regenerative braking model has been incorporated in NREL's HEV system simulation called ADVISOR. Code modules that have been changed to implement the new regenerative model are described. Resulting outputs are compared to the baseline regenerative braking model in the parent code. The behavior of the HEV system (battery state of charge, overall fuel economy, and emissions characteristics) with the baseline and the proposed regenerative braking strategy are first compared.

Engine models with fully coupled dynamic effects of the engine components can be constructed through the use of commercial multibody dynamics codes, such as ADAMS and DADS. These commercial codes provide a modeling platform for very general mechanical systems and the time and effort required to learn how to use them may preclude their use for some engine designers. In this paper, we review an alternative and specialized modeling platform that functions as a template for engine design. Relative to commercial codes, this engine design template employs a recursive formulation of multibody dynamics, and thus it leads directly to the minimum number of equations of motion describing the dynamic response of the engine by a priori satisfaction of kinematic constraints. This is achieved by employing relative coordinates in lieu of the absolute coordinates adopted in commercial multibody dynamics codes. This engine modeling tool requires only minimal information for the input data.

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.