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Viewing 271 to 300 of 22467
2014-04-01
Technical Paper
2014-01-1546
Guanyu Zheng, Fengshuang Wang, Suying Zhang, Jianhua Zhang, Jianzhong Tao, Zhiguo Zhao, Jianqing Fan
Abstract In order to satisfy China IV (equivalent to EU IV) emission regulations, an unconventional design concept was proposed with injector closely coupled with SCR can body. The benefit of this design is that the urea decomposition pipe was removed or drastically shortened, resulting in much smaller packaging space and lower cost of the whole system. However, the resulting short urea mixing distance generates concerns on low urea mixing efficiency and risks of urea deposits. In particular, airless urea injectors tend to generate incomplete evaporation of urea water solution, resulting in high risks of urea deposits. New aftertreatment mixing structures need to be developed to resolve these technical challenges. To this end, stepwise and systematic enhancements of the design have been employed, resulting in multiple designs to eventually meet a set of performance targets, including emission reduction efficiency, reagent mixing, urea evaporation, ammonia and velocity distribution, back pressure, and urea deposits.
2014-04-01
Technical Paper
2014-01-1542
Krishna Kamasamudram, Ashok Kumar, Jinyong Luo, Neal Currier, Aleksey Yezerets, Thomas Watkins, Larry Allard
Abstract An operational challenge associated with SCR catalysts is the NH3 slip control, particularly for commercial small pore Cu-zeolite formulations as a consequence of their significant ammonia storage capacity. The desorption of NH3 during increasing temperature transients is one example of this challenge. Ammonia slipping from SCR catalyst typically passes through a platinum based ammonia oxidation catalyst (AMOx), leading to the formation of the undesired byproducts NOx and N2O. We have discovered a distinctive characteristic, an overlapping NH3 desorption and oxidation, in a state-of-the-art Cu-zeolite SCR catalyst that can minimize NH3 slip during temperature transients encountered in real-world operation of a vehicle. In this work we show new insights, gained from NH3 temperature programmed desorption and oxidation experiments, into the Cu-zeolite catalyst functions responsible for the overlap of NH3 desorption and oxidation characteristics and the impact of hydrothermal treatment on these functions.
2014-04-01
Technical Paper
2014-01-1539
Shun Hong Long, Lianhua Tang, Guodong Yan, Ben Niu, Guanyu Zheng, Fengshuang Wang, Suying Zhang, Jianhua Zhang, Jianzhong Tao
Abstract To satisfy China IV emissions regulations, diesel truck manufacturers are striving to meet increasingly stringent Oxides of Nitrogen (NOx) reduction standards. Heavy duty truck manufacturers demand compact urea SCR NOx abatement designs, which integrate injectors, NOx sensors and necessary components on SCR can in order to save packaging space and system cost. To achieve this goal, aftertreatment systems need to be engineered to achieve high conversion efficiencies, low back pressure, no urea deposit risks and good mechanical durability. Initially, a baseline Euro IV Urea SCR system is evaluated because of concerns on severe deposit formation. Systematic enhancements of the design have been performed to enable it to meet multiple performance targets, including emission reduction efficiency and low urea deposit risks via improved reagent mixing, evaporation, and distribution. Acoustic performance has been improved from the baseline system as well. The optimized system improved ammonia uniformity, eliminated urea deposits, improved NOx conversion efficiency while satisfying existing EU III installation packing space.
2014-04-01
Technical Paper
2014-01-1541
Shubham Sharma, Naveen Kumar, Sambhav Jain, Sidhant Kumar
Abstract The present consumption rates and heavy dependence on fossil fuels pose a humongous threat to the environment. The increased pollution in urban areas is already causing serious sociological, ecological and economic implications. The issue of energy security led governments and researchers to look for alternate means of renewable and environment friendly fuels. Biodiesel has been one of the promising, and economically viable alternatives. The biodiesels are reported to cause reduction in CO, HC and PM emissions. However, NOx emissions are increased in case of biodiesel in CI engine. Therefore, a Urea-SCR over Fe-ZSM5 honeycomb substrate (400cpsi) zeolite catalyst after treatment system is an effective technology to reduce emissions for biodiesel applications. Exhaust gases pass through the catalyst and reactions take place along its surface, consequently converting NOx into nitrogen and H2O. This conversion compliments the functioning of fish oil biodiesel in reducing the overall emissions.
2014-04-01
Technical Paper
2014-01-1532
Nic van Vuuren
Abstract The implementation of stringent nitrogen oxides (NOx) emissions reduction legislation in Europe and North America is driving the introduction of new exhaust aftertreatment systems, including those that treat NOx under the high-oxygen conditions typical of lean-burn engines. One increasingly common solution, referred to as Selective Catalytic Reduction (SCR), comprises a catalyst that facilitates the reactions of ammonia (NH3) with the exhaust nitrogen oxides (NOx) to produce nitrogen (N2) and water (H2O). It is customary with these systems to use a liquid aqueous urea solution, typically at a 32% concentration of urea (CO(NH2)2). The solution is referred to as AUS-32, and is also known under its commercial name of AdBlue® in Europe, and DEF - Diesel Exhaust Fluid - in the USA. The urea solution is injected into the exhaust and transformed to NH3 by various mechanisms for the SCR reactions. Urea injection systems using AUS-32 are now in production and becoming a widespread mature technology on many on-road automotive and off-road vehicle applications.
2014-04-01
Technical Paper
2014-01-1531
Joel Michelin, Frederic Guilbaud, Alain Guil, Ian Newbigging, Emmanuel Jean, Martina Reichert, Mario Balenovic, Zafar Shaikh
Abstract Future Diesel emission standards for passenger cars, light and medium duty vehicles, require the combination of a more efficient NOx reduction performance along with the opportunity to reduce the complexity and the package requirements to facilitate it. With the increasing availability of aqueous urea, DEF or AdBlue® at service stations, and improved package opportunities, the urea SCR technical solution has been demonstrated to be very efficient for NOx reduction; however the complexity in injecting and distributing the reductant remains a challenge to the industry. The traditional exhaust system contains Diesel Oxidation Catalysts (DOC), Diesel Particulate Filters (DPF) and Selective Catalytic Reduction (SCR), all require additional heat to facilitate each of their specific functions. With some particular package scenarios the SCR catalyst maybe found after the particulate filter where elaborate light-off strategies need to be deployed to ensure activation under many different driving regimes.
2014-04-01
Technical Paper
2014-01-1535
Hongsuk Kim, Cheon Yoon, Junho Lee, Hoyeol Lee
Abstract One of most effective NOx control technology of modern diesel engines is SCR with ammonia. Current NOx reduction systems are designed to use a solution of urea dissolved in water as a source of ammonia. However, the liquid urea systems have technical difficulties, such as a freezing point below −11°C and solid deposit formation in the exhaust temperature below 200°C. The objective of this study is to investigate the possibility of a new ammonia generation system that uses low-cost solid ammonium salt, such as solid urea and ammonium carbonate. The result shows that ammonium carbonate is more suitable than solid urea because of low decomposition temperature and no change to the other ammonium salt during the decomposition process. This paper also shows the NOx reduction capability of the new ammonia delivery system that uses ammonium carbonate.
2014-04-01
Technical Paper
2014-01-1527
Xiangyu Feng, Yunshan Ge, Jianwei Tan, Jiaqiang Li, Yao Zhang, Chenglei Yu
Abstract The NOx conversion efficiency of vanadium-based SCR catalyst is lower under low temperature. Utilizing an exhaust analyzer, the effects of electrically heated catalyst on the performance of vanadium-based SCR catalyst under low temperature was studied on the engine test bench. The inlet temperature of SCR catalyst without the electrically heated catalyst were in the range of 150°C∼270°C under various steady engine modes, and the NSR (Normalized Stoichiometric Ratio) was set as 0.4,0.6,0.8,1.0. The results showed that under the space velocity of 20000h−1, with the application of the electrically heated catalyst, the inlet temperature of SCR increased about 19.9°C on average and the NOx conversion efficiency improved about 8.0%. The NOx conversion efficiency increased 1.7%∼8.6% at the temperatures of 150°C∼174°C, and 1.0%∼15.9% at the temperatures of 186°C∼270°C. The experiment space velocity properties indicated that with the electrically heated catalyst, the inlet temperature increase and the increasing rate of the NOx conversion efficiency both decreased with the increasing space velocity.
2014-04-01
Technical Paper
2014-01-1530
Joel Op de Beeck, Kevin Slusser, Neall Booth
Abstract Automotive SCR systems are dimensioned to reduce NOx efficiently in normal driving conditions. In markets such as North America and Europe, extreme winter conditions are common over a period of many weeks where temperatures are usually below DEF (Diesel Exhaust Fluid) freezing temperatures at −11°C (12°F). In previous studies and applications, DEF was heated in the tank in a dedicated pot or alternatively by a standardized central heater. Due to the local character of these heating solutions, it was not possible to thaw the full tank volume. The objective of this study is to demonstrate how to significantly improve performance of the SCR system in cold weather conditions for passenger car, light commercial vehicles and SUV applications. The performance improvement is demonstrated by sustainability testing showing how much of the full tank content can be thawed and made available for injection in the exhaust system. Based on maximum average dosing rates of 250 g/h, external temperatures down to −40°C and depending on the tank shape the heater is designed to optimize tank heating performance.
2014-04-01
Technical Paper
2014-01-1529
Jongik Jeon, Hyongman Seo, Kangwon Lee, Soonhyung Kwon, Kisong Bae
Abstract This paper describes how to meet LEVII ULEV70 emission standards and minimize fuel consumption with the combined NOx after-treatment (LNT+SCR) system for diesel vehicles. Through analysis of LNT's functionality and characteristics in a LNT+SCR combined after-treatment system, allowed a new control strategy to be established, different from the existing LNT-only system. In the 200°C or higher condition where SCR can provide the most stable NOx conversion efficiency, rich regeneration of LNT was optimized to minimize LNT deterioration and fuel consumption. Optimized mapping between rapid heat up strategy and raw NOx reduction maximized LNT's NOx conversion efficiency during the intervals when it is not possible for SCR to purify NOx This study used bench aged catalysts which were equivalent to 150K full useful life. During the Highway (HFET) driving cycle when the SCR conversion rate is generally high, fuel economy was improved by minimization DeNOx in LNT and improvement of the engine combustion efficiency.
2014-04-01
Technical Paper
2014-01-1524
Matthieu Lecompte, Stephane Raux, Arnaud Frobert
Abstract The selective catalytic reduction (SCR) based on urea water solution (UWS) is an effective way to reduce nitrogen oxides (NOx) emitted by engines. The high potential offered by this solution makes it a promising way to meet the future stringent exhaust gas standards (Euro6 and Tier2 Bin5). UWS is injected into the exhaust upstream of an SCR catalyst. The catalyst works efficiently and durably if the spray is completely vaporized and thoroughly mixed with the exhaust gases before entering. Ensuring complete vaporization and optimum mixture distribution in the exhaust line is challenging, especially for compact exhaust lines. Numerous parameters affect the degree of mixing: urea injection pressure and spray angle, internal flow field (fluid dynamics), injector location …. In order to quantify the mixture quality (vaporization, homogeneity) upstream of the SCR catalyst, it is proposed to employ non intrusive optical diagnostics techniques such as laser induced fluorescence (LIF).
2014-04-01
Technical Paper
2014-01-1516
Kihong Kim, Rahul Mital, Takehiro Higuchi, Seomoon Chan, Chang Hwan Kim
Abstract Diesel particulate filter (DPF) is a widely used emission control device on diesel vehicles. The DPF captures the particulate matter coming from the engine exhaust and periodically burns the collected soot via the regeneration process. There are various trigger mechanisms for this regeneration, such as distance, time, fuel and simulation. Another method widely used in the industry is the pressure drop across the filter. During calibration, relation between the pressure sensor reading and soot mass in the filter is established. This methodology is highly effective in successful DPF operation as pressure sensor is a live signal that can account for any changes in engine performance over time or any unforeseen hardware failures. On the other hand, any erroneous feedback from the sensor can lead to inaccurate soot mass prediction causing unnecessary regenerations or even needless DPF plugging concerns. A similar phenomenon was observed on certain vehicles where the DPF pressure reading jumped inexplicably leading to DPF plugging concerns.
2014-04-01
Technical Paper
2014-01-1518
Homayoun Ahari, Michael Zammit, Luis Cattani, Jason Jacques, Thomas Pauly
Abstract To meet TierII/LEVII emissions standards, light duty diesel (LDD) vehicles require high conversion efficiencies from the Aftertreatment Systems (ATS) for the removal of both Hydrocarbon (HC) and Nitrogen Oxide (NOx) species. The most populous configuration for LDD ATS have the Selective Catalytic Reduction (SCR) catalyst positioned on the vehicle behind the close coupled Diesel Oxidation Catalyst (DOC) and Catalyzed Diesel Particulate Filter (CDPF). This SCR position may require active heating measures which rely on the DOC/CDPF to provide heat through the combustion of HC and CO in the exhaust. Although DOCs are always impacted by their aging conditions, some aging conditions are shown to be both reversible and irreversible. Under continuous, high speed and high mileage conditions such as experienced in a modified Standard Road Cycle (SRC) or as it is better known, the High Speed Cycle (HSC), it is shown that the DOC's activity can deteriorate initially but significantly recover over repeated FTP-75 test cycles on fully aged catalysts.
2014-04-01
Technical Paper
2014-01-1513
Bernhard Kern, Stephanie Spiess, Joerg Michael Richter
Abstract With the growing awareness about the presence of fine/ultra fine particulates in the ambient air and their negative impact on climate and health, some regions of the world have started to look closer at the contribution of road traffic. Since Gasoline engines, in particular when injecting fuel directly into the combustion chamber, proved to emit relevant numbers of particulates, even hardly visible, the growing share of Gasoline DI engines and their small size of particulate emissions is a concern. To address the same, the EU has already set limits for the particulate number with EU6 from 2015 onwards. The US considers setting challenging limits by particulate mass. Since mass of ultra fine particulates is very low and difficult to measure, experts investigate if a measurement by number might better address the particular concern. The implementation of a coated Particulate Filter enables meeting not only basic demands during traditional emission test cycles. Also the particulate emissions during highly transient and high load driving conditions are reduced effectively.
2014-04-01
Technical Paper
2014-01-1508
Stephen Johnson, Peter Croswell, Michael Smith
Abstract “Zoning” a catalytic converter involves placing higher concentrations of platinum group metals (PGM) in the inlet portion of the substrate. This is done to optimize the cost-to-performance tradeoff by increasing the reaction rate at lower temperatures while minimizing PGM usage. A potentially useful application of catalyst zoning is to improve performance using a constant PGM mass. A study was performed to assess what the optimum ratio of front to rear palladium zone length is to achieve the highest performance in vehicle emission testing. Varying the zone ratio from 1:1 to 1:9 shows a clear hydrocarbon performance optimum at a 1:5.66 (15%/85%) split. This performance optimum shows as both a minimum in FTP75 non-methane organic gas (NMOG) emissions as well as a minimum in hydrocarbon, carbon monoxide, and nitrogen oxide light-off temperature. Overall, an improvement of 18%, or 11 mg/mi of combined NMOG+NOx emissions was obtained without using additional PGM. This study shows how the competing forces of active PGM site concentration and available surface area interact in modern three way catalyst design.
2014-04-01
Technical Paper
2014-01-1506
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.
2014-04-01
Technical Paper
2014-01-1503
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.
2014-04-01
Technical Paper
2014-01-1504
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.
2014-04-01
Technical Paper
2014-01-1501
Keiichi Hayashizaki, Mitsuru Hosoya, Hiroshi Urushibara, Hiroshi Hirabayashi, Hideki Honda, Yoichiro Nakamura
Abstract 1 To meet the Japan Post New-Long-Term (Japan 2009) emissions regulation introduced in 2009, The Hydrocarbon Selective Catalytic Reduction (HC-SCR) system for the NOx emission with a diesel fuel was chosen among various deNOx after-treatment systems (the Urea-SCR, the NOx storage-Reduction Catalyst and so on). The HC-SCR was adopted, in addition to combustion modification of diesel engine (mainly cooled EGR) as the New DPR system. The New DPR system for medium and light duty vehicles was developed as a world's first technology by Hino Motors. Advantages of the New DPR are compact to easy-to-install catalyst converter and no urea solution (DEF) injection (regardless urea infrastructure) as compared the Urea-SCR system. This study is reported to introduce the New DPR system, and to clarify the reduction effect of the Original DPR on the regulated emissions (NOx, PM, HC and CO) and emissions level of the unregulated emissions (N2O, CH4, HCHO, CH3CHO, 1,3-butadiene, benzene, Benzo[a]pyrene and NH3), based on the measurement results.
2014-04-01
Technical Paper
2014-01-1502
Erica King, David Wallace, E. Robert Becker
Abstract Platinum Group Metal (PGM) use is dominated by the automotive industry. The PGM market is sensitive to shifts in the drivers for emission control and the delicate supply-demand balance. Technology shifts in the emission control industry are particularly impactful because of the automotive market's dominance and the consequent ability to significantly affect metal prices. On the supply side, evolving ore ratios of platinum, palladium and rhodium, production ramp-up times, geopolitical factors, and labor relations contribute to a challenging production environment. This is mitigated by a growing above-ground supply from spent autocatalysts. The availability of spent autocatalyst is critical to alleviate the pressure on primary supply and is especially important in light of the hurdles primary PGM producers face. This paper reviews technology developments, legislative drivers, and consumer trends in the automotive industry and their impact on PGM demand. Evolving emission regulations for criteria pollutants around the world put pressure on catalyst performance and durability while greenhouse gas standards bring new challenges to the operating environment of these catalysts.
2014-04-01
Technical Paper
2014-01-1616
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.
2014-04-01
Technical Paper
2014-01-1620
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.
2014-04-01
Technical Paper
2014-01-1596
Adam Dempsey, Scott Curran, John Storey, Mary Eibl, Josh Pihl, Vitaly Prikhodko, Robert Wagner, James Parks
Abstract Low temperature combustion (LTC) has been shown to yield higher brake thermal efficiencies with lower NOx and soot emissions, relative to conventional diesel combustion (CDC). However, while demonstrating low soot carbon emissions it has been shown that LTC operation does produce particulate matter whose composition appears to be much different than CDC. The particulate matter emissions from dual-fuel reactivity controlled compression ignition (RCCI) using gasoline and diesel fuel were investigated in this study. A four cylinder General Motors 1.9L ZDTH engine was modified with a port-fuel injection system while maintaining the stock direct injection fuel system. The pistons were modified for highly premixed operation and feature an open shallow bowl design. RCCI operation was carried out using a certification grade 97 research octane gasoline and a certification grade diesel fuel. To study the particulate matter emissions from RCCI operation, particle size distributions were measured with a Scanning Mobility Particle Sizer (SMPS) and total particulate concentration in the exhaust was determined using membrane filters.
2014-04-01
Technical Paper
2014-01-1597
Glenn Lucachick, Aaron Avenido, Winthrop Watts, David Kittelson, William Northrop
Abstract Diesel particulate filter (DPF) technology has proven performance and reliability. However, the addition of a DPF adds significant cost and packaging constraints leading some manufacturers to design engines that reduce particulate matter in-cylinder. Such engines utilize high fuel injection pressure, moderate exhaust gas recirculation and modified injection timing to mitigate soot formation. This study examines such an engine designed to meet US EPA Interim Tier 4 standards for off-highway applications without a DPF. The engine was operated at four steady state modes and aerosol measurements were made using a two-stage, ejector dilution system with a scanning mobility particle sizer (SMPS) equipped with a catalytic stripper (CS) to differentiate semi-volatile versus solid components in the exhaust. Gaseous emissions were measured using an FTIR analyzer and particulate matter mass emissions were estimated using SMPS data and an assumed particle density function. Though the tested engine is predicted to largely meet current US particle mass standards it has significantly higher particle number emissions compared to the Euro 6 solid particle number emissions standard.
2014-04-01
Technical Paper
2014-01-1600
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.
2014-04-01
Technical Paper
2014-01-1607
Qi Jiao, Rolf D. Reitz
Abstract 3-D Computational Fluid Dynamics (CFD) simulations have been performed to study particulate formation in a Spark-Ignition (SI) engine under premixed conditions. A semi-detailed soot model and a chemical kinetic model, including poly-aromatic hydrocarbon (PAH) formation, were coupled with a spark ignition model and the G equation flame propagation model for SI engine simulations and for predictions of soot mass and particulate number density. The simulation results for in-cylinder pressure and particle size distribution (PSDs) are compared to available experimental studies of equivalence ratio effects during premixed operation. Good predictions are observed with regard to cylinder pressure, combustion phasing and engine load. Qualitative agreements of in-cylinder particle distributions were also obtained and the results are helpful to understand particulate formation processes.
2014-04-01
Technical Paper
2014-01-1612
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.
2014-04-01
Technical Paper
2014-01-1613
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.
2014-04-01
Technical Paper
2014-01-1571
Shaohua Hu, Suiyun Zhang, Satya Sardar, Shiyan Chen, Inna Dzhema, Shiou-Mei Huang, David Quiros, Huaiwei Sun, Christopher Laroo, L. James Sanchez, James Watson, M.-C. Oliver Chang, Tao Huai, Alberto Ayala
Abstract The California Air Resources Board (CARB) adopted the Low Emission Vehicle (LEV) III regulations in January 2012, which lowered the particulate matter (PM) emissions standards for light-duty vehicles (LDVs) from 10 milligrams per mile (10 mg/mile) to 3 mg/mile beginning with model year (MY) 2017 and 1 mg/mile beginning with MY 2025. To confirm the ability to measure PM emissions below 1 mg/mile, a total of 23 LDVs (MY pre-2004 to 2009) were tested at CARB's Haagen-Smit Laboratory (HSL) (10 LDVs) and the United States Environmental Protection Agency's (US EPA) National Vehicle and Fuel Emissions Laboratory (NVEFL) (13 LDVs) using the federal test procedure (FTP) drive schedule. One LDV with PM emissions ranging from 0.6 - 0.8 mg/mile was tested at three CARB HSL test cells to investigate intra-lab and inter-lab variability. Reference, trip, and tunnel filter blanks were collected as part of routine quality control (QC) procedures. Reference and trip blanks showed the well-documented filter weighing and handling process had negligible impact on final test values.
2014-04-01
Technical Paper
2014-01-1580
Tomohiro Minagawa, Daiji Nagaoka, Hiroyuki Yuza, Teruo Nakada, Takeyuki Kamimoto
Abstract The filtration efficiency of a DPF drops when it suffers a failure such as melting and cracks during regeneration. And then, on-board diagnostics (OBD) device has become needed worldwide to detect a DPF failure. In the development of an OBD soot sensor, evaluation of the sensor demands a portable instrument which can measure the soot concentration for on-board and in-field use. Some of the emission regulations require the in-field emission measurements under normal in-use operation of a vehicle. This study is intended to develop a high sensitivity and high response portable smoke meter for on-board soot measurements and a reference to OBD soot sensors under development. The smoke meter accommodates a 650 nm laser diode, and its principle is based on light extinction in high soot concentration range and backward light scattering for low soot concentration measurement. Raw exhaust sample flows through a thermo-controlled optical tube at a flow rate of 3 liter/min, and the total system unit weighs only 16 kg.
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