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Technical Paper

2000 University of Maryland FutureTruck Design Description

The University of Maryland team converted a model year 2000 Chevrolet Suburban to an ethanol-fueled hybrid-electric vehicle (HEV) and tied for first place overall in the 2000 FutureTruck competition. Competition goals include a two-thirds reduction of greenhouse gas (GHG) emissions, a reduction of exhaust emissions to meet California ultra-low emissions vehicle (ULEV) Tier II standards, and an increase in fuel economy. These goals must be met without compromising the performance, amenities, safety, or ease of manufacture of the stock Suburban. The University of Maryland FutureTruck, Proteus, addresses the competition goals with a powertrain consisting of a General Motors 3.8-L V6 engine, a 75-kW (100 hp) SatCon electric motor, and a 336-V battery pack. Additionally, Proteus incorporates several emissions-reducing and energy-saving modifications; an advanced control strategy that is implemented through use of an on-board computer and an innovative hybrid-electric drive train.

2050 aircraft engine designs go radical, part 2

In part two of a two-part series, Richard Gardner discusses various aerospace propulsion innovations and continued work by aerospace engineers and scientists to advance aircraft engine technologies to increase efficiency and lower emissions.
Technical Paper

21 Development of a Small Displacement Gasoline Direct Injection Engine

We have developed a small-displacement gasoline direct-injection engine (1.3L). Gasoline direct-injection engines rely on ultra-lean stratified combustion to deliver significantly better fuel economy, and are already used in many practical applications. When gasoline direct-injection is applied to a small-displacement engine, however, the amount of wall wetting of fuel on the piston surface will increase because the traveled length of the fuel spray is short. This may result in problems such as smoke production, high emissions of unburned HC, and poor combustion efficiency.
Technical Paper

24 Noise, Emissions and Fuel Economy Investigation on a Small DI Diesel Using Taguchi Methods

To provide optimal performance of a small DI diesel in relation to noise, emissions and fuel economy, an experimental investigation was carried out using Taguchi methods. A single cylinder 3.5 kW diesel was selected for performance test at different engine speeds, loads and static injection timings. These controlled parameters were varied at three levels and the resulting changes in response variables viz. engine noise, smoke, HC, NOx, CO, CO2 emissions and fuel economy (b.s.f.c) were observed. The levels for low noise, smoke, emissions and b.s.f.c could be predicted and relevant combination of controlled parameters specified. Confirmation engine runs were carried out and the results showed good agreement with the predicted optimized quantities of interest based on Taguchi analysis. The effect of engine parameters to the above responses was evaluated in terms of percent contributions by using analysis of variance.
Technical Paper

25W HID Headlamp - First Series Production in Hybrid Vehicle

Due to the general requirements in the automotive industry to reduce the power consumption, fuel consumption rate and CO2 emission a new HID (High Intensity Discharge) bulb with only 25W is under development for front lighting systems. A first headlamp integrated in a hybrid vehicle is now launched as a first application in the market. The current regulation in ECE allows to get rid of the mandatory headlamp cleaning system and the automatic leveling requirement once the 25W HID bulb is applied. The reason for this is the objective luminous flux of the 25W HID bulb, which emits less than 2000 lm, a boundary defined in the regulation, where a headlamp cleaning and an automatic leveling is requested. That simplifies especially the integration in smaller vehicles and electric and hybrid vehicles. The paper describes the special design of the headlamp, the projector unit, the light performance, packaging advantages and future outlook of further applications in the near future.
Journal Article

25cc HCCI Engine Fuelled with DEE

This paper describes the set-up and testing of a single cylinder 25cc, air cooled, 4-stroke Spark Ignition (SI) engine converted to run in Homogeneous Charge Compression Ignition (HCCI) mode with the aid of various combustion control systems. The combustion control systems were investigated regarding their effects on combustion stability and heat release phasing. Engine operation was compared with unique findings from previous work done on a very small 2-stroke HCCI engine. HCCI engine operation was possible between 1000 - 4000 rpm when using Diethyl Ether (DEE) as the test fuel. Maximum operational fuel-air equivalence ratio (Φ) was 0.75 when operating without Exhaust Gas Recirculation (EGR). This relatively high equivalence ratio was attainable due to thermal gradients induced by the high surface area to volume ratio of the small engine combustion chamber, resulting in high chamber heat transfer.
Technical Paper

2D Residual Gas Visualization in an Optical Direct Injection Spark Ignition Engine with IR Laser Absorption

The spatial distribution of internal exhaust gas recirculation (EGR) is evaluated in an optically accessible direct injection spark ignition engine using near infrared laser absorption to visualize the distribution of the H2O molecule. The obtained overall internal exhaust gas recirculation compares well to gas-exchange cycle calculations and the spatial distributions are consistent with those measured with inverse LIF. The experimental procedures described in this report are designed to be simple and rapidly implemented without the need to resort to unusual optical components. The necessary spectral data of the selected absorption line is obtained from the HITEMP database and is validated with prior experiments carried out in a reference cell. Laser speckle in the images is effectively reduced using a ballistic diffuser.
Technical Paper

2D-Simulation of Ignition Induced by Electrical Discharges

Growing interest in pollutant emission reduction has increased the importance of numerical simulations of spark ignition as a first step in IC engine combustion. In this work, we present simulations involving the coupling of flow, chemical reactions and molecular transport with the discharge processes. The main focus hereby is to investigate the early stages of the formation of a flame kernel in a two-dimensional, cylindrical geometry with electrodes. The computational results shown here include the initial shock-determined phase after the breakdown of the channel, but also the transition to flame propagation for a methane-air mixture.
Technical Paper

3 - Valve Stratified Charge Engines: Evolvement, Analysis and Progression

A historical review of the patents and literature pertaining to 3-valve stratified charge engines is presented in this paper. This very old invention appears to be a practical approach for the “clean engine” being sought for vehicular use since it has the intrinsic capability of simultaneously giving good fuel economy and producing minimal objectionable exhaust emissions. The prime requisites of this engine are a rich prechamber charge and a very lean main chamber charge regardless of prechamber volume, nozzle diameter, valving and spark plug location. Fuel-air equivalence ratios of the charges in the two combustion chambers are significantly important in order to achieve the proper optimization. These ratios should be about 15% rich for the prechamber and 15 to 30% lean for the main chamber at the moment of ignition.
Technical Paper

3 Wet Technology - A Novel Approach for Greener, Efficient, Smart Practice in Automotive Paint Application

The upcoming latest 3-wet Technology is the most ideal design for a Green field project as well as for a brown field facility which provides the best of both worlds. The foremost take away for a brown field project emanates from this technology which demands a smaller foot prints & hence could accommodates a capacity higher than what was perceived during the green field project planning thus saving millions of dollar of investment & giving that extra capacity which today the BRIC countries are thriving for. Apart from making the ideal investment choice, 3 Wet Technology provides impetus to business case in terms of reduction of VOC emission, Energy consumption, Material and labor cost and gaining on Green Environment front as well as leading to smart and Efficient-Paint-Process. The paper depicts the journey of roll out of 3-Wet process in Ford India and creating the bench mark in terms of product quality and process standards and manufacturing practices.
Journal Article

3-Cylinder Turbocharged Gasoline Direct Injection: A High Value Solution for Low CO2 and NOx Emissions

Today turbo-diesel powertrains offering low fuel consumption and good low-end torque comprise a significant fraction of the light-duty vehicle market in Europe. Global CO₂ regulation and customer fuel prices are expected to continue providing pressure for powertrain fuel efficiency. However, regulated emissions for NO and particulate matter have the potential to further expand the incremental cost of diesel powertrain applications. Vehicle segments with the most cost sensitivity like compacts under 1400 kg weight look for alternatives to meet the CO₂ challenge but maintain an attractive customer offering. In this paper the concepts of downsizing and downspeeding gasoline engines are explored while meeting performance needs through increased BMEP to maintain good driveability and vehicle launch dynamics. A critical enabler for the solution is adoption of gasoline direct injection (GDi) fuel systems.
Technical Paper

3-D CFD Analysis of CO Formation in Diesel Combustion - The use of intake air throttling to create reducing atmospheres for NSR catalysts -

The efficiency of the NOx Storage and Reduction (NSR) catalysts used in the aftertreatment of diesel engine exhaust gases can potentially be increased by using reactive reductants such as CO and H₂ that are formed during in-cylinder combustion. In this study, a multi-dimensional computational fluid dynamics (CFD) code coupled with complex chemical analysis was used to study combustion with various fuel after-injection patterns. The results obtained will be useful in designing fuel injection strategies for the efficient formation of CO.
Technical Paper

3-D Catalytic Regeneration and Stress Modeling of Diesel Particulate Filters by ABAQUS FEM Software

The design of reliable DPF systems has proved a complex and demanding task that is increasingly being assisted by modeling. 1-D but also 2-D (axisymmetric) modeling has already been applied in design optimization case studies, with varying degrees of success. The introduction of advanced technology SiC and cordierite filters with modular structure and the need to accurately model transient temperature and stress fields in low space velocity scenarios, made necessary the shift to 3-D modeling. In this paper, 3-D modeling is carried out in an effective and reliable way, by interfacing a well-documented and validated 1-D model with the ABAQUS commercial FEM software. The new modeling methodology proves a powerful tool in the hands of the filter and diesel exhaust system design engineer.
Technical Paper

3-D Diesel Spray Simulations Using a New Detailed Chemistry Turbulent Combustion Model

Until recently, the application of the detailed chemistry approach as a predictive tool for engine modeling has been sort of a “taboo” for different reasons, mainly because of an exaggerated rigor to the chemistry/turbulence interaction modeling. In terms of this ideology, if the interaction cannot be simulated properly, the detailed chemistry approach makes no sense. The novelty of the proposed methodology is the coupling of a generalized partially stirred reactor, PaSR, model with the high efficiency numerics to treat detailed oxidation kinetics of hydrocarbon fuels. In terms of this approach, chemical processes are assumed to proceed in two successive steps: the reaction follows after the micro-mixing is completed on a sub-grid scale.
Technical Paper

3-D Modeling of Diesel Engine Intake Flow, Combustion and Emissions

Manufacturers of heavy-duty diesel engines are facing increasingly stringent, emission standards. These standards have motivated new research efforts towards improving the performance of diesel engines. The objective of the present program is to develop a comprehensive analytical model of the diesel combustion process that can be used to explore the influence of design changes. This will enable industry to predict the effect of these changes on engine performance and emissions. A major benefit of the successful implementation of such models is that engine development time and costs would be reduced through their use. The computer model is based on the three-dimensional KIVA-II code, with state-of-the-art submodels for spray atomization, drop breakup / coalescence, multi-component fuel vaporization, spray/wall interaction, ignition and combustion, wall heat transfer, unburned HC and NOx formation, and soot and radiation.
Technical Paper

3-D Numerical Study of Effect of Injection Parameters Upon the Uniformity of Ammonia in Urea-SCR

Nowadays, due to the stringent engine emission norms, an efficient technique is required to reduce oxides of nitrogen (NOx) from automobiles especially from the lean burn engines. Selective Catalytic Reduction (SCR) is found to be an efficient after treatment method used to reduce oxides of nitrogen (NOx) from the exhaust. However, for light duty vehicles, because of the limited size of the catalysts, ammonia slip nullifies its advantages. Lack of uniformity of ammonia at the SCR monolith entrance causes ammonia slip. This study addresses the effect of injection parameters, location of injector and shape of injector upon the flow parameters, exhaust gas temperature and flow rate. The results obtained from this study provide useful guidelines for optimizing the injection parameters to avoid the ammonia slip. The evaporation of Urea Water Solution (UWS) is also investigated.
Technical Paper

3-D Numerical Study of Flow Mixing in Front of SCR for Different Injection Systems

The urea Selective Catalytic Reduction (SCR) exhaust system has been proved to be the reliable aftertreatment device with the capability of reducing tail pipe NOx emission by 75% to 90%, HC by 50% and Particulate Matter (PM) by 30%. Constrained by increasingly stringent packaging envelope, flow mixing in front of substrate is becoming one of the major concerns to achieve ideal performance of higher NOx conversion and lower ammonia (NH3) slip. Three dimensional CFD simulations are performed in current study to investigate flow mixing phenomenon in a SCR system. First, for a traditional tube injector with single or multiple nozzles, the effects of mass flow rates of injected NH3 and exhaust gas on flow mixing and pressure loss are investigated. Then, a concept of ring shape injector with multiple nozzles are initiated and built for 3-D CFD simulations. The comparisons of flow mixing index and injection pressure are made between two type injectors.
Technical Paper

3-D Numerical Study of Mixing Characteristics of NH3 in Front of SCR

The Urea Selective Catalytic Reduction (SCR) technology is one of the major mature exhaust aftertreatment technologies which are demonstrated to be able to lower tail pipe NOx emission by 90%. The system consists of a urea injection at upstream pipe and a downstream SCR converter. A well mixed flow (exhaust gas and NH3) in front of SCR substrate, which is usually constrained by tight design packaging, is very critical to ensure the desired performance. Current paper addresses the geometrical effects on flow mixing by using three dimensional Computational Fluid Dynamics (CFD) tool. The mixing enhancement is achieved by adding flow mixer. The shapes and locations of flow mixers, as well as the number of blades inside mixer are investigated to show the effect on fluid mixing in downstream along the flow direction. Results show great improvement of flow mixing by adding a delta wing mixer.
Technical Paper

3-D PIV Analysis of Structural Behavior of D.I. Gasoline Spray

Three-dimensional behaviors of direct injection (D.I.) gasoline sprays were investigated using 2-D and 3-D particle image velocimetry (PIV) techniques. The fuel was injected with a swirl type injector for D.I. gasoline engines into a constant volume chamber in which ambient pressure was varied from 0.1 to 0.4 MPa at room temperature. The spray was illuminated by a laser light sheet generated by a double-pulsed Nd:YAG laser (wave length: 532 nm) and the succeeding two tomograms of the spray were taken by a high-resolution CCD camera. The 2-D and 3-D velocity distributions of the droplet cloud in the spray were calculated from these tomograms by using the PIV technique. The effects of the swirl groove flows in the injector and the ambient pressure on the structural behavior of the droplet cloud in the spray were also examined.
Technical Paper

3-D Ultrasound for Medical Imaging in Space

Ultrasound is attractive for medical imaging in space because scanners can be small, lightweight, low power, and have minimal electromagnetic emissions. In addition, unlike conventional 2-D ultrasound. 3-D ultrasound allows an operator with no diagnostic skills to collect high-quality scans that can be interpreted by a remote expert. This allows 3-D ultrasound to be used effectively in remote locations. These capabilities are illustrated by the MUSTPAC-1, a portable 3-D ultrasound telemedicine system recently developed for the U.S. military. Design, implementation, and field experiences with the MUSTPAC-1 are discussed, and extensions for use in space are proposed.