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Article
2014-04-01
IMSA Tudor United SportsCar Championship promotes a variety of green technologies to link racing to the road.
Technical Paper
2014-04-01
Piotr Bielaczyc, Joseph Woodburn, Andrzej Szczotka
Direct injection gasoline engines have been gaining popularity for passenger car applications, particularly in the EU. It is well known that emissions of particulate matter are an inherent disadvantage of spark ignition engine with direct injection. Direct injection of gasoline can lead to the formation of substantial numbers of particulates, a proportion of which survive to be emitted from the vehicle's exhaust. EU legislation limits particle mass (PM) emissions; particle number (PN) is soon to be limited, although an opt-out means that dedicated filters will not be required immediately. A range of tests were conducted on a pool of Euro 5 passenger cars in BOSMAL's climate controlled emissions laboratory, using EU legislative test methodology. In addition, further measurements were performed (particle size distribution, tests at multiple ambient temperatures). Results were compared to legislative limits and order of magnitude comparisons were made with emissions from indirect injection gasoline and direct injection Diesel engines.
Technical Paper
2014-04-01
Donghui Qi, Chia-Fon Lee, Yilu Lin
Abstract Biodiesel is considered one of the most promising alternative fuels to petrol fuels. In this study, an attempt has been made to investigate and compare the effect of fuel injection pressure, injection timing, and exhaust gas recirculation (EGR) ratio on the particle size distributions and exhaust emissions of the diesel and biodiesel produced from waste cooking oil (WCO) used in a common rail direct injection (CRDI) diesel engine. The engine tests were conducted at two injection pressures (800 and 1600 bar), two injection timings (25 and 5 deg before top dead center (bTDC) and three EGR ratios (10%, 20% 30%) at a constant fuel injection energy per stroke and engine speed (1200 r/min). The results indicated that carbon monoxide (CO) and hydrocarbon (HC) emissions of biodiesel were slightly lower, but nitrogen oxide (NOx) emissions were slightly higher, than those of diesel fuel under most operating conditions. Biodiesel engine emitted lower soot particle concentration than diesel engine.
Technical Paper
2014-04-01
Gabriele Di Blasio, Mauro Viscardi, Michela Alfè, Valentina Gargiulo, Anna Ciajolo, Carlo Beatrice
Abstract Nowadays, alcohol fuels are of increasing interest as alternative transportation biofuels even in compression ignition engines because they are oxygenated and producible in a sustainable way. In this paper, the experimental research activity was conducted on a single cylinder research engine provided with a modern architecture and properly modified in a dual-fuel (DF) configuration. Looking at ethanol the as one of the future environmental friendly biofuels experimental campaign was aimed to evaluate in detail the effect of the use of the ethanol as port injected fuel in diesel engine on the size, morphology, reactivity and chemical features of the exhaust emitted soot particles. The engine tests were chosen properly in order to represent actual working conditions of an automotive light-duty diesel engine. A proper engine Dual-Fuel calibration was set-up respecting prefixed limits on in-cylinder peak firing pressure, cylinder pressure rise, fuel efficiency and gaseous emissions.
Technical Paper
2014-04-01
Benjamin Reuter, Daniel Gleyzes, Markus Lienkamp
Abstract In this analysis we assess the life cycle greenhouse gas (GHG) emissions of four types of vehicles which might play a role in achieving future emission reductions: vehicles using compressed natural gas (CNG), battery electric vehicles (BEVs), mild hybrid CNG vehicles and range extended BEVs. Our analysis covers the manufacturing processes of these vehicles and their use as a city taxi in Singapore. We also consider upstream emissions from fuel and electricity production. All necessary parameters are derived from an intensive literature review and the model for calculating the life cycle emissions is presented. The influence of data uncertainties is analyzed by parameter variations within different scenarios. The calculation results are found to be quite robust: The BEV and the mild hybrid CNG vehicle similarly show very low GHG emissions within all scenarios whereas the pure CNG vehicle always ranks the worst. In an additional scenario we also assessed the influence of an improved electricity generation with lower emissions in the future.
Technical Paper
2014-04-01
Yang Li, Jian Xue, Kent Johnson, Thomas Durbin, Mark Villela, Liem Pham, Seyedehsan Hosseini, Zhongqing Zheng, Daniel Short, George Karavalakis, Akua Asa-Awuku, Heejung Jung, Xiaoliang Wang, David Quiros, Shaohua Hu, Tao Huai, Alberto Ayala
Abstract This study provides one of the first evaluations of the integrated particle size distribution (IPSD) method in comparison with the current gravimetric method for measuring particulate matter (PM) emissions from light-duty vehicles. The IPSD method combines particle size distributions with size dependent particle effective density to determine mass concentrations of suspended particles. The method allows for simultaneous determination of particle mass, particle surface area, and particle number concentrations. It will provide a greater understanding of PM mass emissions at low levels, and therefore has the potential to complement the current gravimetric method at low PM emission levels. Six vehicles, including three gasoline direct injected (GDI) vehicles, two port fuel injected (PFI) vehicles, and one diesel vehicle, were tested over the Federal Test Procedure (FTP) driving cycle on a light-duty chassis dynamometer. PM mass emissions were determined by the gravimetric (MGravimetric) and IPSD (MIPSD) methods.
Technical Paper
2014-04-01
Justin E. Ketterer, James S. Wallace, Greg J. Evans
Abstract Biodiesel and other renewable fuels are of interest due to their impact on energy supplies as well as their potential for carbon emissions reductions. Waste animal fats from meat processing facilities, which would otherwise be sent to landfill, have been proposed as a feedstock for biodiesel production. Emissions from biodiesel fuels derived from vegetable oils have undergone intense study, but there remains a lack of data describing the emissions implications of using animal fats as a biodiesel feedstock. In this study, emissions of NOx, unburned hydrocarbons and particulate matter from a compression ignition engine were examined. The particulate matter emissions were characterized using gravimetric analysis, elemental carbon analysis and transmission electron microscopy. The emissions from an animal fat derived B20 blend were compared to those from petroleum diesel and a soy derived B20 blend. No statistically significant differences were observed between the fuels in the gaseous emissions.
Technical Paper
2014-04-01
Dimitrios Savvidis, Konstantinos Bounos, Christos Loakimidis
Abstract Real world engine emissions measurements were carried out from the University of Antwerp in Belgium and more than 600 passenger cars were measured when entering and leaving two different University campuses. All measurements were done according to the European Commission Directive 2010/48/EU on roadworthiness tests for motor vehicles and their trailers. A database, including a wide variety of vehicles with completely different engine specifications and technological characteristics (engine size, emissions standards exhaust after-treatment devices etc.) has been created and various parameters influencing emissions will be examined. The influence of various parameters on NOx emissions was considered and discussed in this paper. Important conclusions have been made for diesel vehicles and presented in this work. Cold and hot start engine emissions were taken and analyzed in order to determine the percentage that NOx emission increased over the years. A comparison of different generation of cars is also included in the research.
Technical Paper
2014-04-01
Keith Vertin, Aaron Reek
The U.S. EPA has proposed a Tier 3 rule to lower average NMOG+NOx emissions from new light duty vehicles by approximately 80% from 2017 to 2025. Early in this time period, gasoline-fueled vehicles are expected to use technologies similar to California SULEV-II/PZEV certified models currently in limited production. These late model vehicles feature engine control systems that promote rapid catalyst light-off and are designed for ultra-high catalyst conversion efficiency. To enable the use of advanced catalyst coatings and materials, the EPA is also proposing to limit the sulfur content of gasoline to an annual average of 10 ppm while optionally maintaining the current maximum cap of 80 ppm. Fuel sulfur is known to poison precious metal-based catalysts, and the impact on emissions is well understood for older technology vehicles. However, there is a lack of test data on the sensitivity and reversibility of late model vehicle emissions to sulfur. This study evaluated six late model vehicles to determine if the exhaust emissions effects caused by exposure to 80 ppm high sulfur fuel were reversible, after the vehicles were refueled with 10 ppm sulfur fuel.
Technical Paper
2014-04-01
Xu Chen, Ashok Kumar, David Klippstein, Randy Stafford, Changsheng Su, Ying Yuan, James Zokoe, Paul McGinn
Abstract Experimental evaluation of soot trapping and oxidation behaviors of various diesel particulate filters (DPF) has been traditionally hampered by several experimental difficulties, such as the deposition of soot particles with well-characterized and consistent properties, and the tracking of the soot oxidation rate in real time. In the present study, an integrated bench flow-reactor system with a soot generator has been developed and its capabilities were demonstrated with regards to: Consistently and controllably loading soot on DPF samples; Monitoring the exhaust gas composition by FTIR, including quantification of the soot oxidation rate using CO and CO2; Measuring soot oxidation characteristics of various DPF samples. Soot particles were produced from a laminar propane co-flow diffusion flame. The production rate of particulate matter (PM) of the soot generator, which is tunable by adjusting the air to fuel ratio of the propane flame, can be set within a range from tens of mg to 400 mg per hour.
Technical Paper
2014-04-01
Fernando Ortenzi, Giovanni Pede, Ennio Rossi
Abstract The adoption of composed (hybrid) lead acid battery-supercapacitor (SC) storage systems is able to improve performances (availability, durability, range) of an electric microcar. As a matter of fact, the supercapacitors extend the operation time not only by improving the energy efficiency (thanks to a higher contribution of regenerative braking), but also by reducing the power down caused by voltage drop at higher discharge rates. The integration of battery with supercapacitors requires careful analysis and calculation of the relationship between battery peak power and size of the SC bank, needed to have a balanced composition of the hybrid storage system. For this purpose, the optimization process, summarized here, is based on the combination of a conventional lead-acid battery and a commercial SC, with the vehicle running the ECE15 driving cycle. A Matlab/Simulink model has been developed in order to characterize the benefits of the adoption of such hybrid storage system and experimental tests have been used to calibrate it.
Technical Paper
2014-04-01
Gangfeng Tan, Ming Chen, Haobo Xu, Bing Luo, Jiameng Wang
Abstract Vacuum cleaning vehicle is the necessary equipment for the Municipal Sanitation Department to keep the road surface clean and the dust subsidence system is the heart unit for the proper function of the cleaning vehicle. The reasonable design of this system could increase the load capacity of the vehicle and be convenient for the garbage collecting and dumping. Meanwhile, the engine power could be relatively reduced and the influence on the environment duo to the dusty air in the outlet could be also effectively improved. In the study, the gravity dedusting principle is used firstly for structure design to reduce the flow rate of dust particles inside the lower part of the dust subsidence system. The ruleless collision loss among dust particles is reduced and thereby the fan power is saved. By means of a reasonable separated chamber design and the use of inertia baffle, the sort management for dust particles is developed and the work stress of the export filter is released observably.
Technical Paper
2014-04-01
Hassan Ali Khairallah, Umit Koylu
Abstract During the past decade, considerable efforts have been made to introduce alternative fuels for use in conventional diesel and gasoline engines. There is significant interest in adding hydrogen to a diesel engine to reduce emissions and improve efficiency. With the rapid increase in computational capabilities, computational fluid dynamics (CFD) codes have become essential tools for the design, control, and optimization of dual fuel engines. In the present study, a reduced chemical kinetics mechanism, consisting of 52 reactions and 29 chemical species for n-heptane fuel combustion, was incorporated with detailed chemical kinetics consisting of 29 reactions for hydrogen including additional nitrogen oxidation. This reaction mechanism was coupled with a 3D CFD model based on AVL FIRE software to investigate the performance and emission characteristics of a diesel engine with low amounts of hydrogen addition. The model was validated by the experimental results and then employed to examine important parameters that have significant effects on the engine performance.
Technical Paper
2014-04-01
Silvana Di Iorio, Paolo Sementa, Bianca Maria Vaglieco, Francesco Catapano
Abstract The use of methane as supplement to liquid fuel is one of the solution proposed for the reduction of the internal combustion engine pollutant emissions. Its intrinsic properties as the high knocking resistance and the low carbon content makes methane the most promising clean fuel. The dual fuel combustion mode allows improving the methane combustion acting mainly on the methane slow burning velocity and allowing lean burn combustion mode. An experimental investigation was carried out to study the methane-gasoline dual fuel combustion. Methane was injected in combustion chamber (DI fuel) while gasoline was injected in the intake manifold (PFI fuel). The measurements were carried out in an optically accessible small single-cylinder four-stroke engine. It was equipped with the cylinder head of a commercial 250 cc motorcycles engine representative of the most popular two-wheel vehicles in Europe. UV-visible spectroscopy measurements were performed to analyze the combustion process with high spatial and temporal resolution.
Technical Paper
2014-04-01
Valentin Soloiu, Alejandro Rivero-Castillo, Martin Muinos, Marvin Duggan, Spencer Harp, Wallace Peavy, Sven Wolter, Brian Vlcek
Abstract This study presents the combustion and emissions characteristics of Reactivity Controlled Combustion Ignition (RCCI) produced by early port fuel injection (PFI) of low reactivity n-butanol (normal butanol) coupled with in cylinder direct injection (DI) of cottonseed biodiesel in a diesel engine. The combustion and emissions characteristics were investigated at 5.5 bars IMEP at 1400 RPM. The baseline was taken from the combustion and emissions of ULSD #2 which had an ignition delay of 13° CAD or 1.5ms. The PFI of n-butanol and DI of cottonseed biodiesel strategy showed a shorter ignition delay of 12° CAD or 1.45ms, because of the higher CN of biodiesel. The combustion proceeded first by the ignition of the pilot (cottonseed biodiesel) BTDC that produced a premixed combustion phase, followed by the ignition of n-butanol that produced a second spike in heat release at 2° CAD ATDC. The addition of n-butanol into the cycle reduced the compression and peak temperature by 100K and resulted in 35% NOx and 90% soot reduction.
Technical Paper
2014-04-01
Yuwei Zhao, Ying Wang, Shenghua Liu
Abstract Premixed charge compression ignition (PCCI) combustion has been shown to be a promising combustion technique to improve the combustion process and simultaneously reduce both Nitrogen oxides (NOx) and particulate matter (PM) emissions. The combination of port dimethyl ether (DME) induction and in-cylinder diesel direct-injection compression ignition (DICI) combustion was studied in a YTR 2105 engine. The main purposes of this paper were to investigate the effects of DME introduction on the combustion and emission characteristics of a diesel engine. Results obtained revealed that PCCI combustion process was composed of the homogeneous charge compression ignition (HCCI) combustion and conventional diffusion combustion. As the DME quantity was increased, the start of combustion (SOC) was advanced. The peak values of in-cylinder pressure and mass averaged temperature increased as well as the maximum heat release rate of DME HCCI combustion. But the maximum heat release rate of diesel diffusion combustion decreased.
Technical Paper
2014-04-01
Debabrata Barik, Murugan Sivalingam
Abstract The present study was aimed to run the diesel engine only with two renewable fuels in a dual fuel mode. The karanja methyl ester (KME) derived from karanja oil was used as an injected fuel, and the biogas obtained from the anaerobic digestion of pongamia pinnata (Karanja) de-oiled cakes, was used as a secondary fuel in a single cylinder, four stroke, air cooled, direct injection (DI) diesel engine. Four different flow rates of biogas, viz., 0.3 kg/h, 0.6 kg/h, 0.9 kg/h and 1.2 kg/h were inducted along with the air in the suction of the engine. The results of the experiment were compared with those of diesel and KME operations. Biogas inducted at a flow rate of 0.9 kg/h was found to be the best among all the flow rates, in terms of the performance and emission of the engine. The dual fuel operation showed a higher BSEC than that of diesel operation at full load. In dual fuel operation, about 22% of KME replacement was possible with the biogas flow rate of 0.9 kg/h at full load.
Technical Paper
2014-04-01
Mohammed Moore Ojapah, Hua Zhao, Yan Zhang
Abstract In recent years, in order to develop more efficient and cleaner gasoline engines, a number of new engine operating strategies have been proposed and many have been studied on different engines but there is a lack of comparison between various operating strategies and alternative fuels at different SI modes. In this research, a single cylinder direct injection gasoline engine equipped with an electro-hydraulic valve train system has been commissioned and used to study and compare different engine operation modes. In this work, the fuel consumption, gaseous and particulate emissions of gasoline and its mixture with ethanol (E15 and E85) were measured and analysed when the engine was operated at the same load but with different load control methods by an intake throttle, reduced intake valve duration, and positive overlap.
Technical Paper
2014-04-01
Dai Liu, Hongming Xu, Ramadhas Arumugam Sakunthalai
Abstract Biodiesel is an oxygenated alternative fuel made from vegetable oils and animal fats via transesterification and the feedstock of biodiesel is diverse and varies between the local agriculture and market scenarios. Use of various feedstock for biodiesel production result in variations in the fuel properties of biodiesel. In this study, biodiesels produced from a variety of real world feedstock was examined to assess the performance and emissions in a light-duty engine. The objective was to understand the impact of biodiesel properties on engine performances and emissions. A group of six biodiesels produced from the most common feedstock blended with zero-sulphur diesel in 10%, 30% and 60% by volume are selected for the study. All the biodiesel blends were tested on a light-duty, twin-turbocharged common rail V6 engine. Their gaseous emissions (NOx, THC, CO and CO2) and smoke number were measured for the study. The emphasis of the investigation is the correlations of the fuel properties such as cetane number, fuel density, GHV (gross heat value) of combustion and oxygen content with the emissions of smoke, THC and NOx.
Technical Paper
2014-04-01
Harveer Singh Pali, Naveen Kumar, Chinmaya Mishra
Abstract In the present study, ethanol was added in lower proportions to non-edible vegetable oil “Schleichera oleosa” or “Kusum”, to evaluate various performance and emission characteristics of a single cylinder; diesel engine. For engine's trial, four samples were prepared with 5%, 10%, 15% and 20% ethanol in kusum oil (v/v) and the blends were named as E5K95, E10K90, E15K85 and E20K80 respectively. Neat Kusum oil was named as K100. The results indicated that brake thermal efficiency (BTE) was found to increase with increase in volume fraction of ethanol in the kusum oil. E5K95, E10K90, E15K85 and E20K80 test fuels exhibited maximum BTE of 25.4%, 26.4%, 27.4% and 27.7% respectively as compared to 23.6% exhibited by the neat Kusum oil. Similarly, full load brake specific energy consumption (BSEC) decreased from 16.3MJ/kWh in case of neat Kusum oil to 15.1MJ/kWh for E20K80 with an almost linear reduction pattern with increased ethanol composition in the test fuel. Full load carbon monoxide emissions were found to be 0.18% volume for neat Kusum oil which was reduced to 0.1% for E20K80.
Technical Paper
2014-04-01
S.M. Remmert, R.F. Cracknell, R. Head, A. Schuetze, A.G.J. Lewis, S. Akehurst, J.W.G. Turner, A. Popplewell
Increasingly strict government emissions regulations in combination with consumer demand for high performance vehicles is driving gasoline engine development towards highly downsized, boosted direct injection technologies. In these engines, fuel consumption is improved by reducing pumping, friction and heat losses, yet performance is maintained by operating at higher brake mean effective pressure. However, the in-cylinder conditions of these engines continue to diverge from traditional naturally aspirated technologies, and especially from the Cooperative Fuels Research engine used to define the octane rating scales. Engine concepts are thus key platforms with which to screen the influence of fundamental fuel properties on future engine performance. ‘ULTRABOOST’, a collaborative research project which is co-funded by the Technology Strategy Board (TSB), the UK's innovation agency, is a downsized, highly boosted, 2.0L in-line 4 cylinder prototype engine, designed to achieve 35% CO2 emissions reduction without compromising the performance of a 5.0L V8 naturally aspirated production engine.
Technical Paper
2014-04-01
Christian Lohfink, Dennis Wiese, Wolfgang Reiser
Abstract Although in the European Union in general no metal containing additives are used, in 2009 a limitation of manganese in gasoline fuel up to 6 mg manganese per liter was introduced in the revised Fuels Quality Directive. In this paper the influences and risks of metal-based additives on the aging of exhaust system components were detected, using the example of the currently allowed manganese content of 6 mg per liter. The legislative endurance test, the Standard Road Cycle (SRC) over the useful life period of 160,000 km conforming to EC Regulation 692/2008 was used. Investigations were carried out with two endurance tests with metal-free-fueled and metal-containing-fueled (reference fuel plus metallic additive) vehicles on a certified chassis dynamometer. The two identical vehicles were both equipped with a typical state of the art downsized DISI engine with Euro 5 application. Euro 5 reference fuel was used as base gasoline. Exhaust emissions were analyzed in fixed intervals over run time in the form of NEDC tests.
Technical Paper
2014-04-01
Huayu Tian, Baigang Sun, Haichun Yao, Hongyang Tang, Qinghe Luo
Abstract Nowadays, the world is facing severe energy crisis and environment problems. Development of hydrogen fuel vehicles is one of the best ways to solve these problems. Due to the difficulties of infrastructures, such as the hydrogen transport and storage, hydrogen fuel vehicles have not been widely used yet. As a result, Hydrogen-gasoline dual-fuel vehicle is a solution as a compromise. In this paper, three way catalytic converter (TWC) was used to reduce emissions of hydrogen-gasoline dual-fuel vehicles. On wide open throttle and load characteristics, the conversion efficiency of TWC in gasoline engine was measured. Then the TWC was connected to a hydrogen internal combustion engine. After switching the hydrogen and gasoline working mode, emission data was measured. Experiment results show that the efficiency of a traditional TWC can be maintained above 85%., while it works in a hydrogen-gasoline dual-fuel alternative working mode.
Technical Paper
2014-04-01
Matteo De Cesare, Federico Stola, Cosimo Senni, Alfredo Di Monte, Stefano Sgatti
Abstract The Selective Catalytic Reduction (SCR) system, installed on the exhaust line, is currently widely used on Diesel heavy-duty trucks and it is considered a promising technique for Euro 6 compliancy for light and medium duty trucks and bigger passenger cars. Moreover, new more stringent emission regulations and homologation cycles are being proposed for Euro 6c stage and they are scheduled to be applied by the end of 2017. In this context, the interest for SCR technology and its application on light-duty trucks is growing, with a special focus on its potential benefit in term of fuel consumption reduction, thanks to combustion optimization. Nevertheless, the need to warm up the exhaust gas line, to meet the required NOx conversion efficiency, remains an issue for such kind of applications. In this work, the activity performed on different Euro 5-compliant light-duty vehicles, equipped with SCR, to fulfill Euro 6 emission level with fuel saving respect to current production level, is described.
Technical Paper
2014-04-01
Anna Fathali, Mats Laurell, Fredrik B. Ekström, Annika Kristoffersson, Bengt Andersson, Louise Olsson
Abstract The effect of various fuel-cut agings, on a Volvo Cars 4-cylinder gasoline engine, with bimetallic three-way catalysts (TWCs) was examined. Deactivation during retardation fuel-cut (low load) and acceleration fuel-cut (high load, e.g. gearshift or traction control) was compared to aging at λ=1. Three-way catalysts were aged on an engine bench comparing two fuel-cut strategies and their impact on of the life and performance of the catalysts. In greater detail, the catalytic activity, stability and selectivity were studied. Furthermore, the catalysts were thoroughly analyzed using light-off and oxygen storage capacity measurements. The emission conversion as a function of various lambda values and loads was also determined. Fresh and 40-hour aged samples showed that the acceleration fuel-cut was the strategy that had the highest contribution towards the total deactivation of the catalyst system. Also, the retardation fuel-cut was found to be detrimental to the catalyst system but not to the same extent as an acceleration fuel-cut.
Technical Paper
2014-04-01
Seung-Jae Yi, Hyung Kee Kim, Sergio Quelhas, Christopher Giler, Dinh Dang, Sang Beom Kim
Abstract A SULEV proposal was investigated for a Hyundai Elantra 1.8L Nu Engine, combining advanced catalyst technologies with optimized engine management control. A washcoat system using 20% less PGM loading and an optimized EMS calibration were developed to meet the 50% development target of the LEV III SULEV30 standards. This paper highlights revisions made to the new control and catalyst systems which include, 1) improved light-off time and cold-start emissions, 2) optimized cold lambda control, 3) reduced number of fuel cut events, 4) a new catalyst technology to match exhaust gas characteristics, and 5) a Pd-only front catalyst with reduced PGM.
Technical Paper
2014-04-01
Hsiao-Lan Chang, Hai-Ying Chen, Kwangmo Koo, Jeffery Rieck, Philip Blakeman
Stricter emission standards in the near future require not only a high conversion efficiency of the toxic air pollutants but also a substantial reduction of the greenhouse gases from automotive exhaust. Advanced engines with improved fuel efficiency can reduce the greenhouse gas emissions; their exhaust temperature is, however, also low. This consequently poses significant challenges to the emission control system demanding the catalysts to function at low temperatures both during the cold start period and under the normal engine operation conditions. In this paper, we will introduce a gasoline Cold Start Concept (gCSC™) technology developed for advanced stoichiometric-burn gasoline engines to meet future stringent emission regulations. To improve the low temperature performance of three-way catalysts, a novel Al2O3/CeO2/ZrO2 mixed oxide was developed. Compared to conventional CeO2/ZrO2 mixed oxides with similar compositions, the new material exhibits higher oxygen storage capacity especially at low temperatures and is more thermally durable.
Technical Paper
2014-04-01
Hideki Goto, Kazuyoshi Komata, Shigekazu Minami
Abstract Among the platinum group metals (PGMs), rhodium (Rh) is known as an exceedingly valuable element for automotive catalysts due to its powerful catalytic function. Because Rh is a costly material, it is paramount to enhance its catalytic function in three-way catalysts (TWCs). This work reports results on the palladium (Pd)-Rh combination which assists the catalytic function of Rh. XPS and XRD are used to observe the Rh characteristics, and engine dynamometer and vehicle testing are conducted to measure catalytic performance and quantify the emission benefits of the Pd-Rh interaction in TWCs. It is well known that Pd-Rh forms a core-shell structured alloy with Rh in its core. This alloy exerts a large negative impact on NOx performance. However, it is inferred from our analyses that highly-dispersed Pd and Rh particles within a certain Pd/Rh atomic ratio prevent this deterioration phenomenon. In this work XPS analysis shows adding Pd increases the Rh0 concentration on the Rh surface when Pd is allocated in proximity to Rh, and the concentration of Rh0 created through the Pd-Rh interaction reaches a maximum at a certain Pd/Rh atomic ratio.
Technical Paper
2014-04-01
Antonino La Rocca, Gianluca Di Liberto, Paul Shayler, Christopher Parmenter, Mike Fay
The determination of size distribution of soot particles and agglomerates in oil samples using a Nanosight LM14 to perform Nanoparticle Tracking Analysis (NTA) is described. This is the first application of the technique to sizing soot-in-oil agglomerates and offers the advantages of relatively high rates of sample analysis and low cost compared to Transmission Electron Microscopy (TEM). Lubricating oil samples were drawn from the sump of automotive diesel engines run under a mix of light duty operating conditions. The oil samples were diluted with heptane before analysing. Results from NTA analysis were compared with the outputs of a more conventional analysis based on Dynamic Light Scattering (DLS). This work shows that soot-in-oil exists as agglomerates with average size of 115 nm. This is also in good agreement with TEM analysis carried out in a previous work. NTA can measure soot particles in polydisperse oil solutions and report the size distribution of soot-in-oil aggregates. NTA allows for an estimation of soot mass contained in the soot-laden oil samples.
Technical Paper
2014-04-01
Xin Wang, Yunshan Ge
Abstract Compressed natural gas (CNG) is widely used as an alternative option in spark ignition engines because of its better fuel economy and in part cleaner emissions. To cope with the haze weather in Beijing, about 2000 gasoline/CNG dual-fuel taxis are servicing on-road. According to the government's plan, the volume of alternative fuel and pure electric vehicle will be further increased in the future. Thus, it is necessary to conduct an evaluation on the effectiveness of alternative fuel on curbing vehicular emissions. This research examined the regulated emissions and particulate matter of gasoline/CNG dual-fuel taxi over New European Driving Cycle (NEDC). Emission tests in gasoline- and CNG-fuelled, cold- and warm-start modes were done for all five taxies. Test vehicles, Hyundai Elantra, are powered by 1.6L spark-ignited engines incorporated with 5-gear manual gearboxes. The taxis were registered in May and June, 2013, and their millage was within 3500 and 10000 km on odometer when the emission tests were performed.
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