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Viewing 1 to 30 of 98
2015-04-14
Technical Paper
2015-01-0497
Monika Filiposka, Ana M. Djuric
Gantry robots are mainly employed for applications, where large workspace is required and with limited higher manipulability to one direction than the others. The Gantries offer very good mechanical stiffness and constant positioning accuracy, but low dexterity. Common gantries are CNC machines with three translational joints XYZ (3DOF) and usually with an attached wrist (+3DOF). The translational joints are used to move the tool in any position of the 3D workspace. The wrist is used to orient the tool by rotation about X, Y and Z axis. This standard kinematic structure (3T3R) produce the rectangular workspace. In this paper full kinematic model of 6DOF general CNC machine is presented, along with the Jacobian matrix and singularity analysis. Using Denavit-Hartenberg convention, firstly, the general kinematic structure is presented, in order to assign frames at each link. The forward kinematic problem is solved using Maple 17 software.
2015-04-14
Technical Paper
2015-01-1714
Usman Asad, Jimi Tjong
Exhaust gas recirculation (EGR) is the most widely used and effective NOx control strategy in modern diesel engines. The authors have previously demonstrated that the intake dilution provides a reliable and quantitative measure of the EGR effectiveness in reducing NOx emissions (SAE 2014-01-1092). With highly boosted (turbocharged) diesel engines and the lean nature of diesel combustion, the real-time estimation of the intake dilution (intake oxygen) becomes a challenging task since the established relationship between the intake dilution and the EGR rate for naturally aspirated engines becomes invalid. The intake charge dilution at any EGR ratio is a function of engine load and intake pressure, and typically changes during transient events.
2015-04-14
Technical Paper
2015-01-0851
Philip Zoldak, Andrzej Sobiesiak, David Wickman, Michael Bergin
The increased availability of natural gas (NG) in the U.S. has renewed interest in the application of compressed natural gas (CNG) to heavy-duty (HD) diesel engines in order to realize fuel cost savings and reduce pollutant emissions, while increasing fuel economy. Reactivity controlled compression ignition (RCCI) combustion employs two fuels with a large difference in auto-ignition properties that are injected at different times to generate a spatial gradient of fuel-air mixtures and reactivity. Typically, the high octane fuel is premixed followed by injection of a high cetane fuel late in the compression stroke, resulting in a stratified mixture. Researchers have shown that natural gas and diesel RCCI offers improved fuel efficiency and lower NOx and Soot exhaust emissions when compared to conventional diesel diffusion combustion. However natural gas and diesel RCCI engines are load limited by excessively high pressure rise rates and high peak cylinder pressure (>200bar).
2015-04-14
Technical Paper
2015-01-0803
Marko Jeftić, Jimi Tjong, Graham Reader, Meiping Wang, Ming Zheng
Experimental testing was done with a modern compression ignition engine to study the effect of the engine load and the effect of different fuels on the post injection characteristics. Two different fuels were utilized; ultra-low sulphur diesel and n-butanol. The results showed that a post injection can be an effective method for increasing the operating range of the engine load. Engine operation at high load can be limited by the peak cylinder pressure but the test results showed that an early post injection can increase the engine load without increasing the peak in-cylinder pressure. Neat butanol combustion may have a very high peak in-cylinder pressure and a very high peak pressure rise rate even at low load conditions. The test results showed that a butanol post injection can contribute to engine power without significantly affecting the peak pressure rise rate and the peak in-cylinder pressure.
2015-04-14
Technical Paper
2015-01-0808
Tadanori Yanai, Shouvik Dev, Xiaoye Han, Ming Zheng, Jimi Tjong
Neat n-butanol combustion and emissions characteristics were investigated in a compression ignition engine by comparing two fuelling techniques. The engine tests were conducted on a single-cylinder diesel engine with a compression ratio of 18.2 : 1. n-Butanol port fuel injection (PI) system was installed to study Homogeneous Charge Compression Ignition (HCCI) combustion characteristics. An in-house common-rail fuel injection system was used to conduct the direct injection (DI) tests for comparative studies. In the DI case, the ignition timing could be controlled by injection timing even with long ignition delay. The pressure rise rate of the DI could be lowered to less than that of the PI case by retarding the injection timing at the same operating condition without using EGR. The NOx of the DI was higher than that of the PI. However, by using EGR, the NOx was reduced to around 20 ppm, similar to the PI level.
2015-04-14
Technical Paper
2015-01-0687
Guang Wang, Xueyuan Nie, Jimi Tjong
In order to reduce the weight of an automotive engine, an aluminum alloy engine block without cast iron liner has been successfully used to replace the gray cast iron engine. However, the low surface hardness of the aluminum alloy may cause high wear and friction on the aluminum cylinders. To overcome these drawbacks, a few surface processing technologies are used to protect the surface of cylinders. Among them, plasma transferred wire arc (PTWA) thermal spraying coating is becoming popular. Plasma electrolytic oxidation (PEO) coating is also proposed for increasing the wear resistance of aluminum alloy and reducing the friction between the cylinder and piston. In this work, a PEO coating with a thickness of 15 um was prepared, and a high speed pin-on-disc tribometer was used to study the tribological behavior of the coating at oil lubricant conditions. Different surface roughness of the coating and a large range of the sliding speeds were employed for the tests.
2015-03-10
Technical Paper
2015-01-0001
Xiaoye Han, Meiping Wang, Ming Zheng
Alcohol fuels that can be produced from biomass feed stocks offer advantages over petroleum in terms of energy sustainability and security. This work investigates the combustion characteristics and control strategies of HCCI combustion with an alcohol fuel, i.e. n-butanol, on a high compression ratio (18.2: 1) diesel engine. Unlike the majority of HCCI studies, this research utilizes the high compression ratio of the stock engine to enable high efficiency HCCI combustion without assistance from additional intake heating, negative valve overlap, or spark ignition. The research aims to address the challenges related to engine combustion and develop viable control strategies for n-butanol as a cleaner power source to replace conventional diesel fuels. Engine tests are performed under independent control of the intake boost and exhaust gas recirculation. The fuelling strategies for n-butanol include the low-pressure port injection and high-pressure direct injection.
2015-03-10
Technical Paper
2015-01-0003
Xiaoye Han, Meiping Wang, Ming Zheng
As one of the next generation bio-alcohol fuels, n-butanol attracts increasing attention for engine combustion applications. This study investigates neat n-butanol, as a cleaner power source, to directly replace conventional diesel fuels for enabling low temperature combustion on a modern common-rail diesel engine. Systematic engine experiments are carried out evaluate the impacts of the fuel change on the combustion characteristics and exhaust emissions. In correlation to n-butanol’s relatively high oxygen content and volatility but low reactivity, combustion control strategies are developed for enabling clean and efficient combustion. The engine tests are performed at medium engine loads (6~10 bar IMEP) under independent control over the intake boost and EGR. The injection strategies for n-butanol combustion include the single-shot injection and the near-TDC main injection with early pilot injections.
2014-04-01
Technical Paper
2014-01-1321
Philip Zoldak, Andrzej Sobiesiak, Michael Bergin, David D. Wickman
Abstract Reactivity controlled compression ignition (RCCI) combustion employs two fuels with a large difference in auto-ignition properties that are injected at different times to generate a spatial gradient of fuel-air mixtures and reactivity. Researchers have shown that RCCI offers improved fuel efficiency and lower NOx and Soot exhaust emissions when compared to conventional diesel diffusion combustion. The majority of previous research work has been focused on premixed gasoline or ethanol for the low reactivity fuel and diesel for the high reactivity fuel. The increased availability of natural gas (NG) in the U.S. has renewed interest in the application of compressed natural gas (CNG) to heavy-duty (HD) diesel engines in order to realize fuel cost savings and reduce pollutant emissions, while increasing fuel economy. Thus, RCCI using CNG and diesel fuel warrants consideration.
2014-04-01
Technical Paper
2014-01-1298
Tadanori Yanai, Xiaoye Han, Meiping Wang, Graham T. Reader, Ming Zheng, Jimi Tjong
Abstract The study investigated the characteristics of the combustion, the emissions and the thermal efficiency of a direct injection diesel engine fuelled with neat n-butanol. Engine tests were conducted on a single cylinder four-stroke direct injection diesel engine. The engine ran at 6.5 bar IMEP and 1500 rpm engine speed. The intake pressure was boosted to 1.0 bar (gauge), and the injection pressure was controlled at 60 or 90 MPa. The injection timing and the exhaust gas recirculation (EGR) rate were adjusted to investigate the engine performance. The effect of the engine load on the engine performance was also investigated. The test results showed that the n-butanol fuel had significantly longer ignition delay than that of diesel fuel. n-Butanol generally led to a rapid heat release pattern in a short period, which resulted in an excessively high pressure rise rate. The pressure rise rate could be moderated by retarding the injection timing and lowering the injection pressure.
2014-04-01
Technical Paper
2014-01-1294
Prasad Divekar, Xiaoye Han, Shui Yu, Xiang Chen, Ming Zheng
Abstract Conventionally, the diesel fuel ignites spontaneously following the injection event. The combustion and injection often overlap with a very short ignition delay. Diesel engines therefore offer superior combustion stability characterized by the low cycle-to-cycle variations. However, the enforcement of the stringent emission regulations necessitates the implementation of innovative diesel combustion concepts such as the low temperature combustion (LTC) to achieve ultra-low engine-out pollutants. In stark contrast to the conventional diesel combustion, the enabling of LTC requires enhanced air fuel mixing and hence a longer ignition delay is desired. Such a decoupling of the combustion events from the fuel injection can potentially cause ignition discrepancy and ultimately lead to combustion cyclic variations.
2014-04-01
Technical Paper
2014-01-0569
Ishika Zonina Towfic, Jennifer Johrendt
Abstract The development of a collision severity model can serve as an important tool in understanding the requirements for devising countermeasures to improve occupant safety and traffic safety. Collision type, weather conditions, and driver intoxication are some of the factors that may influence motor vehicle collisions. The objective of this study is to use artificial neural networks (ANNs) to identify the major determinants or contributors to fatal collisions based on various driver, vehicle, and environment characteristics obtained from collision data from Transport Canada. The developed model will have the capability to predict similar collision outcomes based on the variables analyzed in this study. A multilayer perceptron (MLP) neural network model with feed-forward back-propagation architecture is used to develop a generalized model for predicting collision severity.
2014-04-01
Technical Paper
2014-01-0734
Luv Aggarwal, Ruth Urbanic, Kush Aggarwal
Abstract Industrial robotic arms and manipulators are systems that offer technological advances in automation, production, and logistical processes. Therefore, it is vital to understand and analyze the reachability and dexterity of such manipulators. This paper presents a reconfigurable algorithm for evaluation and 3D visual representation of the total workspace and singularity space of two and three degrees of freedom open-ended kinematic chains. A manipulator's performance is greatly depreciated at or near singular regions which may occur as subset(s) in its complete workspace. It is therefore crucial to understand the functional workspace of a manipulator for an enhanced performance in an industrial setting. The implementation of this algorithm requires two inputs namely; the joint type(s), rotational (R) or translational (T), and the Denavit-Hartenberg (D-H) parameters of the manipulator.
2014-04-01
Technical Paper
2014-01-0957
Guang Wang, Xueyuan Nie
Abstract Aluminum engines have been successfully used to replace heavy gray cast engines to lighten the car's weight and reduce the fuel consumption. To overcome the aluminum alloys' poor wear resistance, cast iron liners and thermal spraying coatings were used as cylinder bore materials for wear protection. A plasma electrolytic oxidation (PEO) technique had also been proposed to produce an oxide coating on aluminum cylinder bore. The oxide coating can have a low coefficient of friction (COF) and minimum wear shown in the lab tests. To conserve more fuel, the stopping and restarting system was introduced when the vehicle was forced to stop immediately for a short time. When the engine was forced to stop and restart, the reciprocating speed of the piston was very slow, and the friction between the piston and the cylinder was high. In this research, a pin-on-disc tribometer was used to investigate tribological behavior of the oxide coating on an aluminum alloy.
2014-04-01
Journal Article
2014-01-1092
Usman Asad, Jimi Tjong
Abstract Modern diesel engines employ a multitude of strategies for oxides of nitrogen (NOx) emission abatement, with exhaust gas recirculation (EGR) being one of the most effective technique. The need for a precise control on the intake charge dilution (as a result of EGR) is paramount since small fluctuations in the intake charge dilution at high EGR rates may cause larger than acceptable spikes in NOx/soot emissions or deterioration in the combustion efficiency, especially at low to mid-engine loads. The control problem becomes more pronounced during transient engine operation; currently the trend is to momentarily close the EGR valve during tip-in or tip-out events. Therefore, there is a need to understand the transient EGR behaviour and its impact on the intake charge development especially under unstable combustion regimes such as low temperature combustion.
2014-04-01
Journal Article
2014-01-0737
Kush Aggarwal, Ruth Urbanic, Luv Aggarwal
Laser cladding is a method of material deposition through which a powdered or wire feedstock material is melted and consolidated by use of a laser to coat part of a substrate. Determining the parameters to fabricate the desired clad bead geometry for various configurations is problematic as it involves a significant investment of raw materials and time resources, and is challenging to develop a predictive model. The goal of this research is to develop an experimental methodology that minimizes the amount of data to be collected, and to develop a predictive model that is accurate, adaptable, and expandable. To develop the predictive model of the clad bead geometry, an integrated five-step approach is presented. From the experimental data, an artificial neural network model is developed along with multiple regression equations.
2014-01-15
Journal Article
2013-01-9095
Lindita Prendi, Allan King, Edwin Tam
Environmental concerns and rising fuel costs are driving Ontario's municipalities and fleet operators to consider alternative vehicle technologies. Elevated fuel consumption and air emissions are attributed to the unique operations of fleet vehicles and in particular, during idling. While drivers of passenger vehicles may have the option of simply not idling, fleet and emergency vehicle operators, may need to keep the vehicle operating to supply power to critical onboard equipment. These demands may be exacerbated during seasonal, temperature extremes. However, prolonged idling can impose significant environmental and economic burdens. Hybrid vehicles have yet to be utilized widely by Ontario's fleets, but there are other approaches to reduce emissions, including alternative “green” technologies to operate in-vehicle equipment and maintain fleet vehicle capabilities instead of idling.
2013-05-13
Technical Paper
2013-01-1953
Nikolina Samardzic, Colin Novak
This study provides an overview of a novel method for evaluating in-vehicle speech intelligibility using the Speech Intelligibility Index (SII). The approach presented is based on a measured speech signal evaluated at the sentence Speech Reception Threshold (sSRT) in a simulated driving environment. In this context, the impact of different band importance functions in the evaluation of the SII using the Hearing in Noise Test (HINT) in a driving simulator is investigated.
2013-04-08
Technical Paper
2013-01-0283
Usman Asad, Prasad Divekar, Ming Zheng, Jimi Tjong
Low temperature combustion (LTC) strategies such as homogeneous charge compression ignition (HCCI), smokeless rich combustion, and reactivity controlled compression ignition (RCCI) provide for cleaner combustion with ultra-low NOx and soot emissions from compression-ignition engines. However, these strategies vary significantly in their implementation requirements, combustion characteristics, operability limits as well as sensitivity to boundary conditions such as exhaust gas recirculation (EGR) and intake temperature. In this work, a detailed analysis of the aforementioned LTC strategies has been carried out on a high-compression ratio, single-cylinder diesel engine. The effects of intake boost, EGR quantity/temperature, engine speed, injection scheduling and injection pressure on the operability limits have been empirically determined and correlated with the combustion stability and performance metrics.
2013-04-08
Journal Article
2013-01-0173
Andrew D. Clark, Derek O. Northwood, Randy J. Bowers, Xichen Sun, Peter Bauerle
Carburized parts often see use in powertrain components for the automotive industry. These parts are commonly quenched and tempered after the carburizing process. The present study compared the austempering heat treatment to the traditional quench-and-temper process for carburized parts. Samples were produced from SAE 8620, 4320, and 8822 steels and heat treated across a range of conditions for austempering and for quench-and-tempering. Distortion was examined through the use of Navy C-Ring samples. Microstructure, hardness, and Charpy toughness were also examined. X-ray diffraction was used to compare the residual stress found in the case of the components after the quench-and-temper and the austempering heat treatments. Austempering samples showed less distortion and higher compressive residual stresses, while maintaining comparable hardness values in both case and core. Toughness measurements were also comparable between both processes.
2012-04-16
Technical Paper
2012-01-0683
William De Ojeda, Yu Zhang, Kelvin Xie, Xiaoye Han, Meiping Wang, Ming Zheng
Diesel aided by gasoline low temperature combustion offers low NOx and low soot emissions, and further provides the potential to expand engine load range and improve engine efficiency. The diesel-gasoline operation however yields high unburned hydrocarbons (UHC) and carbon monoxide (CO) emissions. This study aims to correlate the chemical origins of the key hydrocarbon species detected in the engine exhaust under diesel-gasoline operation. It further aims to help develop strategies to lower the hydrocarbon emissions while retaining the low NOx, low soot, and efficiency benefits. A single-cylinder research engine was used to conduct the engine experiments at a constant engine load of 10 bar nIMEP with a fixed engine speed of 1600 rpm. Engine exhaust was sampled with a FTIR analyzer for speciation investigation.
2012-04-16
Technical Paper
2012-01-0696
Kohei Fukuda, Abbas Ghasemi, Ronald Barron, Ram Balachandar
Clean diesel engines are one of the fuel efficient and low emission engines of interest in the automotive industry. The combustion chamber flow field and its effect on fuel spray characteristics plays an important role in improving the efficiency and reducing the pollutant emission in a direct injection diesel engine, in terms of influencing processes of breakup, evaporation mixture formation, ignition, combustion and pollutant formation. Ultra-high injection pressure fuel sprays have benefits in jet atomization, penetration and air entrainment, which promote better fuel-air mixture and combustion. CFD modeling is a valuable tool to acquire detailed information about these important processes. In this research, the characteristics of ultra-high injection pressure diesel fuel sprays are simulated and validated in a quiescent constant volume chamber. A profile function is utilized in order to apply variable velocity and mass flow rate at the nozzle exit.
2012-04-16
Technical Paper
2012-01-1112
Dale Edward Haggith, Andrzej Sobiesiak
Research regarding higher efficiency engines and renewable energy has lead to HCCI engine technology as a viable option with the ability to utilize a variety of fuels. With a larger focus on environmental effects the ability of HCCI engines to produce low levels of NOx and potentially other combustion products is another attractive feature of the technology. Biomass gas as a renewable primary fuel is becoming more predominant regarding internal combustion engine research. The simulated fuel in this study replicates compositions derived from real-world gasification processes; the focus in this work corresponds to fuel composition variations and their effects regarding combustion phasing and performance. There are three biomass gas fuel compositions investigated in this study. All compositions consisted of combustibles of CH₄, CO, and H₂ accompanied by CO₂ then balanced with N₂. The CH₄ and CO₂ constituents of each fuel mixture are held constant at 2% and 5% respectively.
2011-08-30
Technical Paper
2011-01-1817
Kelvin Xie, Xiaoye Han, Usman Asad, Graham T. Reader, Ming Zheng
Modern diesel engines were known for producing ultra-low levels of hydrogen and hydrocarbons. However, as emission control techniques such as exhaust gas recirculation (EGR) are implemented to meet stringent NOx standards, the resulting increase in partial-combustion products can be significant in quantity both as pollutants and sources of lost engine efficiency. In this work, a modern common-rail diesel engine was configured to investigate the EGR threshold for elevated carbon monoxide, hydrocarbon, and hydrogen emissions at fixed loads and fixed heat-release phasing. It is noted that increase in hydrocarbons, in particular light hydrocarbons (such as methane, ethylene, and acetylene) was concurrent with ultra-low NOx emissions. Hydrogen gas can be emitted in significant quantities with the application of very high EGR. Under ultra-low NOx production conditions for medium and high load conditions, the light hydrocarbon species can account for the majority of hydrocarbon emissions.
2011-08-30
Journal Article
2011-01-1814
Usman Asad, Xiaoye Han, Ming Zheng
In this work, engine tests were performed to realize EGR-enabled LTC on a single-cylinder common-rail diesel engine with three different compression ratios (17.5, 15 and 13:1). The engine performance was first investigated at 17.5:1 compression ratio to provide baseline results, against which all further testing was referenced. The intake boost and injection pressure were progressively increased to ascertain the limiting load conditions for the compression ratio. To extend the engine load range, the compression ratio was then lowered and EGR sweep tests were again carried out. The strength and homogeneity of the cylinder charge were enhanced by using intake boost up to 3 bar absolute and injection pressure up to 180 MPa. The combustion phasing was locked in a narrow crank angle window (5~10° ATDC), during all the tests.
2011-05-17
Technical Paper
2011-01-1681
Nikolina Samardzic, Colin Novak
Individuals with hearing impairments often report hearing difficulties within the driving environment. This is an ever growing issue given the increasing population of senior aged drivers. In this study, Speech Intelligibility Index (SII) is used to predict in-vehicle speech intelligibility of individuals having common hearing impairments. The effect of hearing threshold levels obtained from audiograms and the impact of vehicle background noise measured for various vehicle operating conditions, road surface types and talker and listener configurations are investigated. This is done by using measured and user-defined speech spectra as described by ANSI S3.5-1997 (Methods for Calculation of the Speech Intelligibility Index). The results demonstrate poor speech intelligibility for most situations considered and provide evidence for the need to improve automotive interior sound quality in terms of speech intelligibility for hearing impaired drivers including aged drivers.
2011-05-17
Technical Paper
2011-01-1660
Ienkaran Arasaratnam, Saeid Habibi, Christopher Kelly, Tony J. Fountaine, Jimi Tjong
Advanced engine test methods incorporate several different sensing and signal processing techniques for identifying and locating manufacturing or assembly defects of an engine. A successful engine test method therefore, requires advanced signal processing techniques. This paper introduces a novel signal processing technique to successfully detect a faulty internal combustion engine in a quantitative manner. Accelerometers are mounted on the cylinder head and lug surfaces while vibration signals are recorded during engine operation. Using the engine's cam angular position, the vibration signals are transformed from the time domain to the crank-angle domain. At the heart of the transformation lies interpolation. In this paper, linear, cubic spline and sinc interpolation methods are demonstrated for reconstructing vibration signals in the crank-angle domain.
2011-04-12
Journal Article
2011-01-0329
William De Ojeda, Tytus Bulicz, Xiaoye Han, Ming Zheng, Frederick Cornforth
Extensive empirical work indicates that exhaust gas recirculation (EGR) is effective to lower the flame temperature and thus the oxides of nitrogen (NOx) production in-cylinder in diesel engines. Soot emissions are reduced in-cylinder by improved fuel/air mixing. As engine load increases, higher levels of intake boost and fuel injection pressure are required to suppress soot production. The high EGR and improved fuel/air mixing is then critical to enable low temperature combustion (LTC) processes. The paper explores the properties of the Fuels for Advanced Combustion Engines (FACE) Diesel, which are statistically designed to examine fuel effects, on a 0.75L single cylinder engine across the full range of load, spanning up to 15 bar IMEP. The lower cetane number (CN) of the diesel fuel improved the mixing process by prolonging the ignition delay and the mixing duration leading to substantial reduction of soot at low to medium loads, improving the trade-off between NOx and soot.
2010-12-01
Technical Paper
2010-01-1582
Joseph Maiorana, Bruce P. Minaker
In this study the capabilities of a semi-active suspension and an active roll suspension are evaluated for comparison with a passive suspension. The vehicle used is a utility truck modeled as a multi-body system in ADAMS/Car while the ECU (electronic control unit) is built in Matlab/Simulink. Cosimulation is used in linking the vehicle model with the controller by exchanging the input and output values of each sub-system with one another. For the simulation models considered, results indicate that for a fish-hook cornering maneuver the semi-active suspension is limited in increasing vehicle performance while the active roll suspension significantly improves it. Further analysis is needed to confirm these findings.
2010-06-09
Article
Collegiate engineering students design and build open-wheel racecars with visions of demonstrating blazing speed on the acceleration pad, superior vehicle handling on the autocross course, and reliability in the endurance event. But safety overrides everything.
Viewing 1 to 30 of 98

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