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Viewing 181 to 210 of 108154
2010-10-25
Journal Article
2010-01-2124
Dongkun Lee, John B. Heywood
An experimental study was performed to develop a more fundamental understanding of the effects of secondary air injection (SAI) on exhaust gas emissions and catalyst light-off characteristics during cold start of a modern SI engine. The effects of engine operating parameters and various secondary air injection strategies such as spark retardation, fuel enrichment, secondary air injection location and air flow rate were investigated to understand the mixing, heat loss, and thermal and catalytic oxidation processes associated with SAI. Time-resolved HC, CO and CO₂ concentrations were tracked from the cylinder exit to the catalytic converter outlet and converted to time-resolved mass emissions by applying an instantaneous exhaust mass flow rate model. A phenomenological model of exhaust heat transfer combined with the gas composition analysis was also developed to define the thermal and chemical energy state of the exhaust gas with SAI.
2010-10-25
Technical Paper
2010-01-2123
Simone Malaguti, Stefano Fontanesi, Elena Severi
The paper investigates the low-temperature cranking operation of a current production automotive Gasoline Direct Injected (GDI) by means of 3D-CFD simulations. Particular care is devoted to the analysis of the hollow cone spray evolution within the combustion chamber and to the formation of fuel film deposits on the combustion chamber walls. Due to the high injected fuel amount and the strongly reduced fuel vaporization, wall wetting is a critical issue and plays a fundamental role on both the early combustion stages and the amount of unburnt hydrocarbons formation. In fact, it is commonly recognized that most of the unburnt hydrocarbon emissions from 4-stroke gasoline engines occur during cold start operations, when fuel film in the cylinder vaporize slowly and fuel can persist until the exhaust stroke.
2010-10-25
Technical Paper
2010-01-2122
Stephen Samuel, Ahmed Hassaneen, Denise Morrey
This work aimed to study nano-scale particulate matter originating from gasoline direct injection engine during cold start and warm up operating conditions and to identify the role of the three-way catalytic converter on nano-scale particulate during cold-start and warm-up operating conditions. This work used a 4-stroke, 1.6 litre, wall guided gasoline direct injected, turbocharged and intercooled SI engine equipped with a three-way catalytic converter for this investigation. It used a fast particle spectrometer for the measurement of exhaust nano-scale particles upto 1000 nm diameter.
2010-10-25
Technical Paper
2010-01-2121
Senthil Kumar Masimalai
Methyl esters were prepared from the mixture of unrefined palm oil (URPO) and D-Limonene oil (DLO) and evaluated for their properties to be used as fuel in a diesel engine. DLO was blended with URPO in different proportions (such as 10%, 15% and 20% by mass) before transesterification to reduce viscosity of the URPO. 15% of DLO and 85% of URPO by mass was found as the optimum based on the optimum yield. Reaction influential factors, such as amount of alcohol, temperature for reaction, reaction time and amount of catalyst have been investigated for the methyl ester of 15% of DLO and 85% of URPO mixture (PODLO15). In the second phase of work, tests were conducted on a single cylinder, air cooled diesel to analyze the performance, emission and combustion characteristics of the methyl ester of PODLO15. Engine tests results indicated reduced brake thermal efficiency with neat URPO as compared to neat diesel. Methyl ester of PODLO15 showed improvement in brake thermal efficiency.
2010-10-25
Journal Article
2010-01-2120
Kapila Wadumesthrige, Nicholas Johnson, Mark Winston-Galant, Haiying Tang, K. Y. Simon Ng, Steven O. Salley
Biodiesel has been widely accepted as an alternative for fossil-derived diesel fuel for use in compression ignition (CI) engines. Poor oxidative stability and cold flow properties restrict the use of biodiesel beyond current B20 blend levels (20% biodiesel in 80% ULSD) for vehicle applications. Maintaining the properties of B20 as specified by ASTM D7476-08 is important because, once out of spec, B20 may cause injector coke formation, fuel filter plugging, increased exhaust emissions, and overall loss of engine performance. While the properties of fresh B20 may be within the specifications, under engine operating and longer storage conditions B20 could deteriorate. In a diesel engine, the fuel that goes to the injector and does not enter the cylinder is recycled back to the fuel tank. The re-circulated fuel returns to the fuel tank at an elevate temperature, which can cause thermal oxidation.
2010-10-25
Technical Paper
2010-01-2119
Andreas Janssen, Martin Muether, Andreas Kolbeck, Matthias Lamping, Stefan Pischinger
Within the Cluster of Excellence “Tailor-Made Fuels from Biomass” at RWTH Aachen University, the Institute for Combustion Engines carried out an investigation program to explore the potential of future biofuel components in Diesel blends. In this paper, thermodynamic single cylinder engine results of today's and future biofuel components are presented with respect to their engine-out emissions and engine efficiency. The investigations were divided into two phases: In the first phase, investigations were performed with rapeseed oil methyl ester (B100) and an Ethanol-Gasoline blend (E85). In order to analyze the impact of different fuel blends, mixtures with 10 vol-% of B100 or E85 and 90 vol-% of standardized EN590 Diesel were investigated. Due to the low cetane number of E85, it cannot be used purely in a Diesel engine.
2010-10-05
Technical Paper
2010-01-2034
Kambiz Rezapour, Kambiz M. Ebrahimi, Alastair S. Wood, Abolfath Nikranjbar
The strict regulation of environmental laws, the oil price and restricted resources has made the vehicle manufacturers to use other energy resources instead of fuel oil. Iran is recognized as the second holder of gas reservoirs in the world and can use hydrocarbon gases broadly in particular compressed natural gas (CNG) as the fuel for vehicles specifically in its public transportation fleet and thereby reduce the consumption of diesel fuel and gasoline. This will bring about the reduction of environmental pollutants and reduce the economic costs of transportation sector. With regard to the climatic situation of Iran and concerning the existence of broad network of gas distribution, CNG is a suitable alternative for other fuels. Therefore, developing bi-fuel engine (gasoline and CNG) in the short and middle term strategy for achieving this important subject will be necessary.
2010-10-05
Technical Paper
2010-01-2027
Satya Panigrahi
A new direction in biocomposite manufacturing is to integrate natural fibers and recycled polymers for manufacturing of some innovative products for various industrial uses including automotive under hood parts. The performance of these new materials are comparable to existing ones even with the replacement of synthetic fiber with biodegradable natural fiber from agricultural residue and with the shift from pure polymer to recycled polymer. Thermoplastic are reinforced with flax fiber mostly used to develop biocomppsite. Most of the research reviewed indicated that very limited work had been done on using flax fiber with recycled post consumer thermoplastic to make biocomposite. The goal of this research is to develop recycled biocomposite material by using flax fiber as a reinforcement and recycled post consumer thermoplastic as matrix and streamline the manufacturing process with optimal processing condition and fiber percentage.
2010-10-05
Technical Paper
2010-01-2028
Satya Panigrahi
This article summarizes an experimental study on the mechanical and thermal properties of high density polyethylene (HDPE) compression molding jute biocomposites. Various type of chemical treatment such as NaOH, silane treatment etc are performed to improve the adhesion between the fibers and the HDPE matrix. Variations in fiber percentage, fiber size are maintained as a function of mechanical properties and thermal properties are studied. Mechanical strength of composite shows that composites with silane and NaOH treated exhibit more mechanical strength than untreated composites. Mechanical properties are assessed by tensile, flexural and hardness test and thermal properties are assessed by melting temperature. From the result obtained, thermal characteristics of the composites can be conclude that composites made with NaOH and silane treatment of fiber exhibit more melting temperature compare to untreated one but not significantly.
2010-10-05
Technical Paper
2010-01-2019
William Schaudt, Darrell Bowman, Walter Wierwille, Richard Hanowski, Chris Flanigan
Rear-end crashes involving heavy trucks occur with sufficient frequency that they are a cause of concern within regulatory agencies. In 2006, there were approximately 23,500 rear-end crashes involving heavy trucks which resulted in 135 fatalities. As part of the Federal Motor Carrier Safety Administration's (FMCSA) goal of reducing the overall number of truck crashes, the Enhanced Rear Signaling (ERS) for Heavy Trucks project was developed to investigate methods to reduce or mitigate those crashes where a heavy truck has been struck from behind by another vehicle. Researchers also utilized what had been learned in the rear-end crash avoidance work with light vehicles that was conducted by the National Highway Traffic Safety Administration (NHTSA) with Virginia Tech Transportation Institute (VTTI) serving as the prime research organization. ERS crash countermeasures investigated included passive conspicuity markings, visual signals, and auditory signals.
2010-10-05
Technical Paper
2010-01-2018
Zhu Wang, Ales Alajbegovic, Jaehoon Han, Tristan Donley, Kevin Horrigan, David Bloch, Melinda Pell, Andrew Holz
A newly developed simulation methodology for a long term, transient tractor cabin cool-down is presented in this paper. The air flow was simulated using a Lattice-Boltzmann Equation (LBE) based 3-dimensional flow solver. The conduction and radiation effects on the solid parts as well as the average cabin air temperature evolution were solved by the thermal solver, which also includes a human comfort model. The simulation results were compared with the measured experimental test data and good agreement was observed validating the developed simulation approach. The developed methodology can be applied to all other ground vehicles cabin comfort applications.
2010-10-05
Technical Paper
2010-01-2017
Abhijit Vishnu Londhe, Suhas Kangde
The ECE R-14, AIS015 safety standard specifies the requirements of the safety belt anchorages namely, minimum numbers, their locations, static strength to reduce the possibility of their failure during accidental crashes for effective occupant restraint and the test procedures. This standard applies to the anchorages of safety belts for adult occupants of forward facing or rearward facing seats in vehicles of categories M and N. ECE R14 ensures the passenger safety during sudden acceleration/retardation and accidents. Early simulations revealed some structural short falls that demanded cabin improvements in order to fulfill regulation requirements for the seal belt anchorage test. This paper describes the innovative design modifications done to meet the seat belt anchorage test. Good correlation with the test is achieved in terms of deformations. These simulation methods helped in reducing the number of intermediate physical tests during the design process.
2010-10-05
Technical Paper
2010-01-2016
Mohamed Khalil
In this paper the study is directed to a condition-based predictive maintenance concept as an alternative policy to determine a fleet's health, for increasing the fleet availability and to reduce the operating cost. The concept is based on predicting the system degradation by using an expert system. Therefore, the decision-maker can calculate the remaining lifetime for any mechanical system. These calculations help the decision-maker in making a repair or replacement decision in a suitable time. An application is presented herein on the cylinder kit components (piston, piston rings and liner) to illustrate the effectiveness of this technique. The results indicate that knowing the wear between the cylinder kit components in automotive engines is very important to plan the maintenance for making the repair or replacement decision in a suitable time.
2010-10-05
Technical Paper
2010-01-2021
Zhixin Liu, Hong Chen, Yongwan Shi, Xiaolong Zhang
Although the chance that occupant's upper limbs were injured is decreased significantly in frontal crash with the popularization of safety belt and airbag, the injury problem of occupant's chest is still most frequent and fatal in traffic accidents. 37 groups of data of C-NCAP crash tests including full frontal crash and offset frontal crash tests were investigated in this paper. The chest injury distributing characteristic of drivers and passengers in these two kinds of crash configurations were obtained, and the effect rules of characteristic parameters on chest injury were summarized.
2010-10-05
Technical Paper
2010-01-2020
Gregory Fitch, Myra Blanco, Richard Hanowski, Paul Rau, Chris Flanigan
On-board Camera/Video Imaging Systems (C/VISs) for heavy vehicles display live images to the driver of selected areas to the sides, and in back of the truck's exterior using displays inside the truck cabin. They provide a countermeasure to blind-spot related crashes by allowing drivers to see objects not ordinarily visible by a typical mirror configuration, and to better judge the clearance between the trailer and an adjacent vehicle when changing lanes. The Virginia Tech Transportation Institute is currently investigating commercial motor vehicle (CMV) driver performance with C/VISs through a technology field demonstration sponsored by the National Highway Traffic Safety Administration (NHTSA) and the Federal Motor Carrier Safety Administration (FMCSA). Data collection, which consists of recording twelve CMV drivers performing their daily employment duties with and without a C/VIS for four months, is currently underway.
2010-10-05
Technical Paper
2010-01-2008
Yang Yang, Benjamin Morris, William Liou
Recent studies have shown that hydraulic hybrid drivelines can significantly improve fuel savings for medium weight vehicles on stop-start drive cycles. In a series hydraulic hybrid (SHH) architecture, the conventional mechanical driveline is replaced with a hydraulic driveline that decouples vehicle speed from engine speed. In an effort to increase the design space, this paper explores the use of a fixed displacement checkball piston pump in an SHH driveline. This paper identifies the potential life-limiting components of a fixed displacement checkball piston pump and examines the likelihood of surface fatigue in the check valves themselves. Numerical analysis in ABAQUS software suggests that under worst case operating conditions, cyclic pressure loading will result in low-cycle plastic deformation of check valve surfaces.
2010-10-05
Technical Paper
2010-01-2014
Chris Merkle, Lisa Kennedy
Manufacturers have engineered high voltage batteries and highly efficient electric motors that have been combined with an internal combustion engine (ICE) or in some cases, replaced the engine altogether. While this advancement is beneficial in many ways, service technicians are faced with new challenges in servicing high voltage vehicle systems. Although highly trained in many areas, today's automotive and commercial vehicle service technicians traditionally have not been trained to work with high voltage (HV). To ensure proper and safe HV service, information and training is critical. This paper will highlight some typical safety precautions and service procedures directed by manufacturers, such as the use of high voltage insulation gloves, proper tools needed and the practices of performing HV disabling procedures including zero voltage checks.
2010-10-05
Technical Paper
2010-01-2013
Marius-Dorin Surcel, Jan Michaelsen, Jean-Sebastien Foisy
The experience with the implementation of IV-ITS (In-vehicle Intelligent Transportation Systems, also know as EOBR or electronic onboard recorders) type tools and services in previous projects showed that there is an opportunity to standardize an infrastructure that would increase a project's rate of success. As such, a project that defined, streamlined and standardized a tech transfer approach to IV-ITS products and services was initiated. Therefore, the objective of the project was to develop a standard procedure based on technology transfer best practices and defining the steps and actions required to increase the rate of success and the optimization of the implementation of IV-ITS products and services. A literature review was conducted to identify technology transfer and implementation best practices and to assist in defining a survey for measuring the success of the implementation of participants in IV-ITS implementation projects.
2010-10-25
Technical Paper
2010-01-2236
Randy P. Hessel, Richard Steeper, Russell Fitzgerald, Salvador Aceves, Daniel Flowers
Recently experiments were conducted on an automotive homogeneous-charge-compression-ignition (HCCI) research engine with a negative-valve-overlap (NVO) cam. In the study two sets of experiments were run. One set injected a small quantity of fuel (HPLC-grade iso-octane) during NVO in varying amounts and timings followed by a larger injection during the intake stroke. The other set of experiments was similar, but did not include an NVO injection. By comparing both sets of results researchers were able to investigate the use of NVO fuel injection to control main combustion phasing under light-load conditions. For this paper a subset of these experiments are modeled with the computational-fluid-dynamics (CFD) code KIVA3V [ 6 ] using a multi-zone combustion model. The computational domain includes the combustion chamber, and intake and exhaust valves, ports, and runners. Multiple cycles are run to minimize the influence of initial conditions on final simulated results.
2010-10-25
Technical Paper
2010-01-2237
Tobias Joelsson, Rixin Yu, Xue-Song Bai, Noriyuki Takada, Ichiro Sakata, Hiromichi Yanagihara, Johannes Lindén, Mattias Richter, Marcus Alden, Bengt Johansson
Temperature stratification plays an important role in HCCI combustion. The onsets of auto-ignition and combustion duration are sensitive to the temperature field in the engine cylinder. Numerical simulations of HCCI engine combustion are affected by the use of wall boundary conditions, especially the temperature condition at the cylinder and piston walls. This paper reports on numerical studies and experiments of the temperature field in an optical experimental engine in motored run conditions aiming at improved understanding of the evolution of temperature stratification in the cylinder. The simulations were based on Large-Eddy-Simulation approach which resolves the unsteady energetic large eddy and large scale swirl and tumble structures. Two dimensional temperature experiments were carried out using laser induced phosphorescence with thermographic phosphors seeded to the gas in the cylinder.
2010-10-25
Technical Paper
2010-01-2234
Abdurrahman Imren, Valeri Golovitchev, Cem Sorusbay, Gerardo Valentino
With the advent of the KIVA-4 code which employs an unstructured mesh to represent the engine geometry, the gap in flexibility between commercial and research modeling software becomes more narrow. In this study, we tried to perform a full cycle simulation of a 4-stroke HD diesel engine represented by a highly boosted research IF (Isotta Fraschini) engine using the KIVA-4 code. The engine mesh including the combustion chamber, intake and exhaust valves and helical manifolds was constructed using optional O-Grids catching a complex geometry of the engine parts with the help of the ANSYS ICEM CFD software. The KIVA-4 mesh input was obtained by a homemade mesh converter which can read STAR-CD and CFX outputs. The simulations were performed on a full 360 deg mesh consisting of 300,000 unstructured hexahedral cells at BDC. The physical properties of the liquid fuel were taken corresponding to those of real diesel #2 oil.
2010-10-25
Technical Paper
2010-01-2235
Tobias Joelsson, Rixin Yu, Johan Sjöholm, Per Tunestal, Xue-Song Bai
This paper presents a computational study of the effects of fuel and thermal stratifications on homogenous charge compression ignition (HCCI) combustion process in a personal car sized internal combustion engine. Stratified HCCI conditions are generated using a negative valve overlap (NVO) technique. The aims of this study are to improve the understanding of the flow dynamics, the heat and mass transfer process and the onset of auto-ignition in stratified charges under different internal EGR rate and NVO conditions. The fuel is ethanol supplied through port-fuel injection; the fuel/air mixture is assumed to be homogenous before discharging to the cylinder. Large eddy simulation (LES) is used to resolve in detailed level the flow structures, and the mixing and heat transfer between the residual gas and fresh fuel/air mixtures in the intake and compression strokes.
2010-10-25
Technical Paper
2010-01-2232
Kim Berglund, Pär Marklund, Roland Larsson, Mayte Pach, Richard Olsson
In the competitive market of the car industry today, companies need to continuously strive to optimize the performance, price and environmental properties of their products in order to survive. Wet clutches, as parts of transmission components of passenger cars are no exception. An understanding of how the wet clutch system functions and fails is necessary to optimize price and service life. The friction characteristics of the wet clutch system are determined by lubricant-surface interactions in the contact between the friction discs. Wet clutch failure can often be associated with the deterioration of friction characteristics which eventually leads to stick-slip or shudder. Consequently, knowledge of why and of how friction characteristics change over time is of the outermost significance to enable the understanding and prediction of wet clutch performance. As the lubricant is an essential component of the wet clutch system, lubricant ageing is a factor of importance.
2010-10-25
Journal Article
2010-01-2245
Michele Battistoni, Carlo Nazareno Grimaldi
The aim of the paper is the comparison of the injection process with different fuels, i.e. a standard diesel fuel and a pure biodiesel. Multiphase cavitating flows inside diesel nozzles are analyzed by means of unsteady CFD simulations using a two-fluid approach with consideration of bubble dynamics, on moving grids from needle opening to closure. Two five-hole nozzles with cylindrical and conical holes are studied and their behaviors are discussed taking into account the different properties of the two fuels. Extent of cavitation regions is not much affected by the fuel type. Biodiesel leads to significantly higher mass flow only if the nozzle design induces significant cavitation which extends up to the outlet section and if the injector needle is at high lift. If the internal hole shaping is able to suppress cavitation, the stabilized mass flows are very similar with both fuels.
2010-10-25
Technical Paper
2010-01-2246
Kevin R. Sholes, Kiyotaka Shouji, Tomohiro Chaya, Jay B. Jeffries, Jason M. Porter, Sung Hyun Pyun, Ronald K. Hanson
Simultaneous crank-angle-resolved measurements of gasoline vapor concentration, gas temperature, and liquid fuel droplet scattering were made with three-color infrared absorption in a direct-injection spark-ignition engine with premium gasoline. The infrared light was coupled into and out of the cylinder using fiber optics incorporated into a modified spark plug, allowing measurement at a location adjacent to the spark plug electrode. Two mid-infrared (mid-IR) laser wavelengths were simultaneously produced by difference-frequency-generation in periodically poled lithium niobate (PPLN) using one signal and two pump lasers operating in the near-infrared (near-IR). A portion of the near-IR signal laser residual provided a simultaneous third, non-resonant, wavelength for liquid droplet detection. This non-resonant signal was used to subtract the influence of droplet scattering from the resonant mid-IR signals to obtain vapor absorption signals in the presence of droplet extinction.
2010-10-25
Technical Paper
2010-01-2243
Jim Barker, G John Langley, Paul Richards
The need to meet the US 2007 emissions legislation has necessitated a change in Diesel engine technology, particularly to the fuel injection equipment (FIE). At the same time as these engine technology changes, legislation has dictated a reduction in fuel sulphur levels and there has also been increased use of fatty acid methyl esters (FAME) or biodiesel as a fuel blending component. The combination of changes to the engine and the fuel has apparently led to a sharp rise in the number of reports of field problems resulting from deposits within the FIE. The problem is usually manifested as a significant loss of power or the engine failing to start. These symptoms are often due to deposits to be found within the fuel injectors or to severe fouling of the fuel filter. The characteristics of the deposits found within different parts of the fuel system can be noticeably different.
2010-10-25
Technical Paper
2010-01-2244
Lucio Postrioti, Michele Battistoni
In the present paper, a detailed numerical and experimental analysis of a spray momentum flux measurement device capability is presented. Particular attention is devoted to transient, engine-like injection events in terms of spray momentum flux measurement. The measurement of spray momentum flux in steady flow conditions, coupled with knowledge of the injection rate, is steadily used to estimate the flow mean velocity at the nozzle exit and the extent of flow cavitation inside the nozzle in terms of a velocity reduction coefficient and a flow section reduction coefficient. In the present study, the problem of analyzing spray evolution in short injection events by means of jet momentum flux measurement was approached. The present research was based on CFD-3D analysis of the spray-target interaction in a momentum measurement device.
2010-10-25
Technical Paper
2010-01-2240
Maria Cárdenas, Diana Martin, Reinhold Kneer
An experimental study on the interaction of sprays from clustered orifices is presented. Droplet size and velocity information has been gained by means of Phase Doppler Anemometry for different nozzle configurations varying the diverging opening angle between clustered sprays from 0° to 15°. These nozzles were investigated under high-pressure (50 bar) and high-temperature (800 K) conditions in a pressure chamber and the results are compared to two standard nozzles with flow rates corresponding either to the flow rate of the cluster nozzle configuration or half of the flow rate of this configuration. Two injection pressures, 600 bar and 1100 bar, were used to investigate all nozzles. This investigation completes the characterization of sprays from the cluster nozzles presented in an earlier work. Findings obtained therein were used to choose the measurement procedure for the present investigation and also to determine the spray width in order to obtain the spray angle.
2010-10-25
Technical Paper
2010-01-2238
Yongli Qi, Hao Liu, Kenneth Midkiff, Paulius Puzinauskas
Today's engine and combustion process development is closely related to the intake port layout. Combustion, performance and emissions are coupled to the intensity of turbulence, the quality of mixture formation and the distribution of residual gas, all of which depend on the in-cylinder charge motion, which is mainly determined by the intake port and cylinder head design. Additionally, an increasing level of volumetric efficiency is demanded for a high power output. Most optimization efforts on typical homogeneous charge spark ignition (HCSI) engines have been at low loads because that is all that is required for a vehicle to make it through the FTP cycle. However, due to pumping losses, this is where such engines are least efficient, so it would be good to find strategies to allow the engine to operate at higher loads.
2010-10-25
Journal Article
2010-01-2242
Scott D. Schwab, Joshua J. Bennett, Steven J. Dell, Julie M. Galante-Fox, Alexander M. Kulinowski, Keith T. Miller
To meet increasingly stringent diesel exhaust emissions requirements, original equipment manufacturers (OEMs) have introduced common rail fuel injection systems that develop pressures of up to 2000 bar (30,000 psi). In addition, fuel delivery schemes have become more complicated, often involving multiple injections per cycle. Containing higher pressures and allowing for precise metering of fuel requires very tight tolerances within the injector. These changes have made injectors more sensitive to fuel particulate contamination. Recently, problems caused by internal diesel injector deposits have been widely reported. In this paper, the results of an investigation into the chemical nature and probable sources of these deposits are discussed. Using an array of techniques, internal deposits were analyzed from on a number of sticking injectors from the field and from OEM test stands in North America.
Viewing 181 to 210 of 108154

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