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Viewing 271 to 300 of 22710
2014-10-13
Technical Paper
2014-01-2651
Vipul Vibhanshu, Ashish Karnwal, Amar Deep, Naveen Kumar
The rising cost and limited availability of crude oil in international market has provided an opportunity to look for substitute of fossil fuel. Scientists all over the world are experimenting on variety of renewable fuels for meeting the future energy demands. Bio origin fuels are fast becoming potential alternative resources to replace the fossil fuels. The vegetable oils, derived from oil seed crops have got 90 to 95% energy value of diesel on volume basis, comparable cetane number and can substitute upto 20% (v/v) of diesel fuel. Mahua seed oil is common ingredient of hydrogenated fat. Two-step transesterification process was employed to synthesize biodiesel from Mahua Oil (Madhuca-indica) and analysis of Physico-chemical properties as well as the combustion, performance and emission characteristics was done by taking 10, 20 and 100 % blend with diesel. The physico-chemical properties of the blends were found to be comparable to diesel.
2014-10-13
Technical Paper
2014-01-2649
Agnese Magno, Ezio Mancaruso, Bianca Maria Vaglieco
Abstract The aim of this study is to investigate the combustion process and pollutant formation in a small compression ignition engine. The engine is a prototype for quadricycles. It was designed to comply with Euro 4 emission standard that is a future regulation for this type of vehicles. Two optical accesses for endoscopes were realized in the first cylinder to investigate the combustion process. Two-color pyrometry method was applied to combustion images in order to detect the flame temperature and the soot concentration. The engine ran with a biodiesel, the rapeseed methyl ester, and a conventional diesel fuel. Operating conditions at the engine speed of 2000 rpm at full and medium load were tested. NOx emissions were measured at exhaust. A smoke meter was used to determine the particulate matter concentration. The sizing and the counting of the particles were performed by means of an engine exhaust particle sizer spectrometer.
2014-10-13
Technical Paper
2014-01-2648
Krishna Kumar V., J. Balaji, Balaji Bandaru, L. Navaneetha Rao
Abstract Off-road BS III CEV (US-TIER III equivalent) emission regulations for diesel engines (i.e. Construction Equipment Vehicles) in India demands a technology upgrade to achieve a large reduction in NOx (>50%) and Particulate Matter (>50%) compared to BS II CEV emission levels. EGR is a widely accepted technology for NOx reduction in off-road engines due to lower initial and operating costs. But EGR has its own inherent deficiency of poor thermal efficiency due to lack of oxygen and further increase in soot adding complexity of meeting PM Emissions. Hence an engine meeting BS III CEV norms without EGR/SCR technologies with low initial investment is most desired solution for Indian off-road segment. This work deals with the development of an off-road diesel engine rating from 56 to 74 kW, focused mainly on in-cylinder optimization with the aid of optimum injection and charging strategies.
2014-10-13
Technical Paper
2014-01-2728
Romaeo Dallanegra, Rinaldo Caprotti
Abstract Internal Diesel Injector Deposits (IDIDs) have been known for some time. With the latest powertrains becoming ever more sophisticated and reliant on efficient fuel delivery, the necessity for a continued focus on limiting their formation remains. Initial studies probed both carbonaceous based/ashless polymeric and sodium salt based IDIDs. The reported occurrence of the latter variety of IDID has declined in recent years as a result of the removal of certain additives from the diesel distribution system. Conversely, ashless polymeric based deposits remain problematic and a regular occurrence in the field.
2014-10-13
Technical Paper
2014-01-2724
Pramod S. Mehta, Thangaraja Jeyaseelan
Abstract Biodiesel is an emerging alternative to fossil diesel for use in compression ignition engines. From environmental standpoint, an increase in nitric oxide (NO) emission from biodiesel fueled engine has been a major concern. Several investigations suggest the role of unsaturated methyl ester as a contributor to biodiesel-NO penalty. The chemical simplicity of biodiesel compared to fossil diesel makes their composition effects amenable to a systematic analysis. In this study, the effects of saturated palm and unsaturated karanja (Pongamia pinnata) biodiesels and their blends (Bio-mix) on compression ignition engine performance, combustion and NO emission are investigated. The combustion and emission characteristics of these fuels are compared with fossil diesel that the neat biodiesel fuels result in improved exhaust emissions except NO with a penalty in fuel economy.
2014-10-13
Technical Paper
2014-01-2729
Paul Hellier, Nicos Ladommatos, Tom Headen, Stephen Bennington
Abstract Improvements in the efficiency of internal combustion engines and the development of renewable liquid fuels have both been deployed to reduce exhaust emissions of CO2. An additional approach is to scrub CO2 from the combustion gases, and one potential means by which this might be achieved is the reaction of combustions gases with sodium borohydride to form sodium carbonate. This paper presents experimental studies carried out on a modern direct injection diesel engine supplied with a solution of dissolved sodium borohydride so as to investigate the effects of sodium borohydride on combustion and emissions. Sodium borohydride was dissolved in the ether diglyme at concentrations of 0.1 and 2 % (wt/wt), and tested alongside pure diglyme and a reference fossil diesel. The sodium borohydride solutions and pure diglyme were supplied to the fuel injector under an inert atmosphere and tested at a constant injection timing and constant engine indicated mean effective pressure (IMEP).
2014-10-13
Technical Paper
2014-01-2727
Hu Li, Laura Campbell, Seyed Hadavi, Job Gava
Abstract Direct use of straight vegetable oil based biofuels in diesel engines without trans-esterification can deliver more carbon reductions compared to its counterpart biodiesel. However, the use of high blends of straight vegetable oils especially used cooking oil based fuels in diesel engines needs to ensure compatible fuel economy with PD (Petroleum Diesel) and satisfactory operational performance. There are two ways to use high blends of SVO (Straight Vegetable Oil) in diesel engines: fixed blending ratio feeding to the engine and variable blending ratio feeding to the engine. This paper employed the latter using an on-board blending system-Bioltec system, which is capable of heating the vegetable oils and feeding the engine with neat PD or different blends of vegetable oils depending on engine load and temperature.
2014-10-13
Technical Paper
2014-01-2730
Lei Zhu, Wugao zhang, Zhen Huang, Junhua Fang
Abstract Because of its cleanness and renewability, biodiesel has a great potential as the alternative of diesel fuel to confront with the increasing energy crisis and environment pollution. In this study, diesel oxidation catalyst (DOC) was used to reduce the typical regulated emission and particulate emission. The combined method of fuel design concept with diesel oxidation catalyst was applied in this study. DOC with Pt catalyst was equipped in the engine test bench in this study. The effects of DOC on diesel engine particulate emission fueled with Euro V diesel fuel, biodiesel and ethanol-biodiesel blends were investigated in this study. It was found that DOC seemed have no effects on NOx emission, while it could improve the oxidation reaction from NO to NO2. In the section of particulate emission, DOC could reduce the particulate mass and number concentration, especially in the range of smaller diameter particles. The SOF could be reduced effectively with DOC.
2014-10-13
Technical Paper
2014-01-2795
Wim van Dam, James Booth, Jimmy Pitta, Gary Parsons
Advancement in Heavy Duty Diesel Engine Oils has, for approximately two decades, been driven by the ever more stringent emission legislation for NOx and Particulates. Over the last few years, the focus has shifted to reducing CO2 emissions and reducing operating cost by improving the engine's fuel economy. With fuel economy as an important new technology driver, the industry is exploring and introducing diesel engine oils of viscosity grades that used to be applied solely in passenger car engines, such as SAE 10W-30 and even SAE 5W-30. To avoid misapplication, API has decided that heavy duty diesel engine oils, most of which are formulated close to the maximum 0.12% phosphorus limit in the API C specification, can no longer add the API S gasoline engine claim.
2014-10-13
Technical Paper
2014-01-2773
Vasu Kumar, Naveen Kumar, Vishvendra Tomar, Gagneet Kalsi
Abstract The world today is facing the effect of the dependence on fossil fuels. Also, the rate of consumption of Fossil derived fuels is alarming. The use of non-conventional energy sources is to be increased so as to tackle the global climatic changes, environmental pollution and also to lower down the rate of depletion of fossil fuels. The urgent need to replace the petroleum products having harmful emissions has leaded us to the Biodiesel. Biodiesel is a well-known alternative for diesel with an advantage over the later because of its biodegradable, less toxic nature, superior lubricity, better emission characteristics and in a way environment friendly. The present study focuses on the comparative study and analysis of performance and emission characteristics of a light duty diesel engine on blends of Fish oil Biodiesel in Diesel and Calophyllum Inophyllum Oil Biodiesel in Diesel.
2014-10-13
Technical Paper
2014-01-2774
Juhani K. Laurikko, Nils-Olof Nylund, Paivi Aakko-Saksa, Sari Mannonen, Ville Vauhkonen, Piritta Roslund
Abstract The Finnish pulp and paper company, UPM, will start a biorefinery in Finland in 2014 to produce advanced renewable diesel in commercial scale. The fuel production is based on using crude tall oil (CTO), a wood-based residue of pulping process, as a raw material. The end product, CTO based renewable diesel called UPM BioVerno, is a novel high quality drop-in diesel fuel resembling fossil diesel. It reduces greenhouse gas emissions by up to 80 % when compared to fossil fuels. In this study, the CTO renewable diesel was studied as a blending component in regular mineral-oil based fossil diesel fuel in field testing. The functionality and performance of four (4) passenger cars was evaluated by comparing e.g. fuel consumption and exhaust emissions of CTO renewable diesel blend (R20UPM) with fossil reference fuel. The field test included 20.000 km on-road driving with each car by experienced drivers from VTT Technical Research Centre of Finland.
2014-10-13
Technical Paper
2014-01-2769
Paul Schaberg, Mark Wattrus
Abstract A study was performed to quantify the impact of blending Fatty Acid Methyl Ester (FAME) with Gas-to-Liquids (GTL) diesel fuel on engine exhaust emissions. Fuels that were considered in the study included blends of GTL and EN590 diesel containing 0, 7, and 20 volume % of Soy and Rapeseed Methyl Ester (SME and RME). Part of the study focused on European engine technology, and tests were performed on a Euro 3 passenger car engine and a Euro V heavy-duty engine. A limited study was performed using a heavy-duty engine meeting the US 2004 emission standards, in which case comparisons between the GTL diesel and FAME blends were made with US 2D and California Air Resources Board (CARB) reference fuels. The results showed particulate mass (PM) reductions to varying degrees with all of the GTL/FAME blends.
2014-10-13
Technical Paper
2014-01-2768
George Karavalakis, Daniel Short, Vincent Chen, Carlos Espinoza, Tyler Berte, Thomas Durbin, Akua Asa-Awuku, Heejung Jung, Leonidas Ntziachristos, Stavros Amanatidis, Alexander Bergmann
Abstract The relationship between ethanol and iso-butanol fuel concentrations and vehicle particulate matter emissions was investigated. This study utilized a gasoline direct injection (GDI) flexible fuel vehicle (FFV) with wall-guided fueling system tested with four fuels, including E10, E51, E83, and an iso-butanol blend at a proportion of 55% by volume. Emission measurements were conducted over the Federal Test Procedure (FTP) driving cycle on a chassis dynamometer with an emphasis on the physical and chemical characterization of particulate matter (PM) emissions. The results indicated that the addition of higher ethanol blends and the iso-butanol blend resulted in large reductions in PM mass, soot, and total and solid particle number emissions. PM emissions for the baseline E10 fuel were characterized by a higher fraction of elemental carbon (EC), whereas the PM emissions for the higher ethanol blends were more organic carbon (OC) in nature.
2014-10-13
Technical Paper
2014-01-2770
Satoshi Kato, Yoshimitsu Kobashi, Yasumitsu Suzuki, Koji Tosa, Katsuyoshi Asaka, Alberto Macamo
Abstract Jatropha biofuel is promising renewal oil to produce biodiesel fuel through transesterification method which is shown in many papers. The ideal diesel alternative fuel obtained considering Jatropha as materials is Fatty Acid Methyl Ester (FAME). It is more desirable than the viewpoint of economical efficiency and CO2 control to operate a diesel engine with Jatropha crude (JC) oil. It is the purpose of this research to examine a possibility of using advantageous JC oil direct use as diesel engine fuel, in consideration of the sustainable production of the Jatropha biofuel in Mozambique. The adaptability to the diesel engine of diesel oil and the mixed fuel of JC was examined. Jatropha crude oil contains phorbol ester (PEs) which is a promoter of cancer. Measurement of the concentration of PEs in an exhaust gas was performed using High Performance Liquid Chromatography (HPLC).
2014-10-13
Technical Paper
2014-01-2782
Junya Iwasaki, Yasunori Shimizu, Hiroshi Fujita, Moritsugu Kasai
Abstract Automobile exhaust gas contains various harmful substances other than carbon dioxide, so exhaust gas post-processing devices have been developed to reduce their environmental load. Engine oil has contributed to the improvement of automobiles' environmental performance due to its excellent fuel-saving and long-drain properties. Recently, the lifetime of an exhaust gas post-processing device has been reported to decrease due to ash and phosphorus in engine oil. We have developed non-phosphorus and non-ash engine oil (NPNA), in which metal-based detergents and zinc dialkyldithiophosphate (ZnDTP) were not contained. We have performed a verification test for NPNA using an actual engine. In a performance test for a diesel particulate filter (DPF), the amount of soot and ash deposited onto a DPF was smaller when NPNA was used than when commercially available engine oil was used.
2014-10-13
Technical Paper
2014-01-2830
Amar Deep, Naveen Kumar, Ashish Karnwal, Dhruv Gupta, Vipul Vibhanshu, Abhishek Sharma, Jitesh Singh Patel
Abstract The interest of using alternative fuels in diesel engines has been accelerated exponentially due to a foreseen scarcity in world petroleum reserves, increase in the prices of the conventional fossil fuels and restrictions on exhaust emissions such as greenhouse gases from internal combustion (IC) engines initiated by environmental concerns. The constant trade-off between efficiency and emissions should be in proper balance with the conventional fuels in a fuel design process for future combustors. Unlike gasoline and diesel, alcohols act as oxygenated fuels. Adding alcohols to petroleum products allows the fuel to combust properly due to the presence of oxygen, which enhances premixed combustion phase, improves the diffusive combustion phase which increases the combustion efficiency and reduces air pollution. The higher activation energy of alcohols leads to better resistance to engine knocking that allows higher compression ratios and greater engine thermal efficiencies.
2014-10-13
Technical Paper
2014-01-2827
Kristin Götz, Anja Singer, Olaf Schröder, Christoph Pabst, Axel Munack, Jürgen Bünger, Jürgen Krahl
Abstract One political and economic aim in Europe is to increase the use of renewable energy resources. In the transport sector, up to 10 % of fossil diesel fuel should be replaced by biogenic fuels by 2020. This also means a reduction in crude oil dependency. In the area of diesel fuel, fatty acid methyl esters are introduced since over 20 years as biodiesel. However, biodiesel can lead to an increase of engine oil dilution in passenger cars with diesel particulate filters. During the regeneration of the particulate filters, there is an entry of fuel components in the engine oil. While most of the diesel fuel (DF) evaporates from the engine oil, biodiesel remains in the oil and can cause sludge formation in the engine. A promising approach to reduce this problem is the use of a new type of biogenic fuel, called hydrotreated vegetable oil (HVO). This is also produced from vegetable oil or animal fat. Like biodiesel, HVO is free of sulfur and any aromatics.
2014-10-13
Technical Paper
2014-01-2824
Piotr Bielaczyc, Andrzej Szczotka, Joseph Woodburn
Abstract Ethanol has a long history as an automotive fuel and is currently used in various blends and formats as a fuel for spark ignition engines in many areas of the world. The addition of ethanol to petrol has been shown to reduce certain types of emissions, but increase others. This paper presents the results of a detailed experimental program carried out under standard laboratory conditions to determine the influence of different quantities of petrol-ethanol blends (E5, E10, E25, E50 and E85) on the emission of regulated and unregulated gaseous pollutants and particulate matter. The ethanol-petrol blends were laboratory tested in two European passenger cars on a chassis dynamometer over the New European Driving Cycle, using a constant volume sampler and analyzers for quantification of both regulated and unregulated emissions.
2014-10-13
Technical Paper
2014-01-2823
Norifumi Mizushima, Daisuke Kawano, Hajime Ishii, Yutaka Takada, Susumu Sato
Abstract Widespread use of biofuels for automobiles would greatly reduce CO2 emissions and increase resource recycling, contributing to global environmental conservation. In fact, activities for expanding the production and utilization of biofuels are already proceeding throughout the world. For diesel vehicles, generally, fatty acid methyl ester (FAME) made from vegetable oils is used as a biodiesel. In recent years, hydrotreated vegetable oil (HVO) has also become increasingly popular. In addition, biomass to liquid (BTL) fuel, which can be made from any kinds of biomass by gasification and Fischer-Tropsch process, is expected to be commercialized in the future. On the other hand, emission regulations in each country have been tightened year by year. In accordance with this, diesel engines have complied with the regulations with advanced technologies such as common-rail fuel injection system, high pressure turbocharger, EGR and aftertreatment system.
2014-10-13
Technical Paper
2014-01-2821
Jonathan Stewart, Roy Douglas, Alexandre Goguet, Cristina Elena Stere, Luke Blades
Abstract One of the most critical aspects in the development of a kinetic model for automotive applications is the method used to control the switch between limiting factors over the period of the chemical reaction, namely mass transfer and reaction kinetics. This balance becomes increasingly more critical with the automotive application with the gas composition and gas flow varying throughout the automotive cycles resulting in a large number of competing reactions, with a constantly changing space velocity. A methodology is presented that successfully switches the limitation between mass transfer and reaction kinetics. This method originally developed for the global kinetics model using the Langmuir Hinshelwood approach for kinetics is presented. The methodology presented is further expanded to the much more complex micro-kinetics approach taking into account various kinetic steps such as adsorption/desorption and surface reactions.
2014-10-13
Technical Paper
2014-01-2841
Jing Qin, Xiang Li, Yiqiang Pei
Abstract The aim of this research is to experimentally investigate the effects of combustion parameters [ignition timings, injection timings, excess air ratio (λ)] and lubricating oil on particulate matter (PM) emissions from a 2.0 L turbo-charged gasoline direct injection (T-GDI) engine fueled with gasoline (octane number = 97), methanol/gasoline blends and pure methanol. The results of this paper show that the PM number concentration mostly presents a typical bimodal distribution in figures. The particle number concentration mainly concentrates in the nucleation mode. With the increase of methanol volume fraction in the blended fuel, the PM emissions decrease significantly. Furthermore, there are few particles when the engine fueled with pure methanol. As advancing ignition timing, the total PM number rises by over about 200%. Under the pre-ignition condition, the higher in-cylinder temperature may also accelerate the formation of the nucleation mode particles.
2014-10-13
Technical Paper
2014-01-2839
Christophe Barro, Philipp Meyer, Konstantinos Boulouchos
Abstract Past research has shown that post injections have the potential to reduce Diesel engine exhaust PM concentration without any significant influence in the NOx emissions. In earlier research it was observed that soot reduction due to a post injection is based on three reasons: increased turbulence (1) and heat (2) from the post injection during soot oxidation and lower soot formation due to smaller main injection for similar load conditions (3). The second effect of heat addition during the soot oxidation is debated in the literature. The experimental investigation presented in the current work provides insight into the underlying mechanisms of soot formation and reduction using post injections under different operating conditions. The experimental data have been obtained using a cylindrical constant volume chamber with high optical access. The soot evolution has been obtained using 2-color-pyrometry.
2014-10-13
Technical Paper
2014-01-2838
Xiangang Wang, Zhangsong Zhan, Tiegang Hu, Zuohua Huang
Abstract Performance and particulate emissions of a modern common-rail and turbocharged diesel engine fueled with diesel and biodiesel fuels were comparatively studied. An electrical low-pressure impactor (ELPI) was employed to measure particle size distribution and number concentration. Two biodiesel fuels, BDFs (biodiesel from soybean oil) and BDFc (biodiesel from used cooking oil), as well as ultra-low sulfur diesel were used. The study shows that biodiesels give higher thermal efficiency than diesel. Biodiesels give obviously lower exhaust gas temperature than diesel under high engine speed. The differences in fuel consumption, thermal efficiency and exhaust gas temperature between BDFs and BDFc are negligible. The first peaks of heat release rate for biodiesels are lower than that of diesel, while the second peaks are higher and advanced for biodiesels. BDFs show slightly slower heat release than BDFc during the first heat release stage at low engine speed.
2014-10-13
Technical Paper
2014-01-2837
Jinyoung Jang, Young-Jae Lee, Ohseok Kwon, Minseob Lee, Jeonghwan Kim
Abstract This study focused on the effect of engine oils on regulated emissions, particulates and fuel economy. Three engine oils of the same SAE grade (synthetic oil with poly alpha olefins (PAOs), Group III base oil, and Group III genuine oil with additive package) were used in one gasoline and one diesel vehicle. A GDI (Gasoline Direct Injection) vehicle and a diesel vehicle without DPF (Diesel Particulate Filter) were selected because those vehicles obviously emit more particulates than port-injection gasoline vehicles and diesel vehicles with DPF. A combined mode consisting of the US EPA emission test cycles FTP-75 and HWFET was used for these tests. HORIBA and PIERBURG gas analyzers were used to measure regulated emissions and fuel economy, respectively. Unregulated emissions and particulates were analyzed by FTIR and PPM-S, respectively. Samples (300 ml) of test engine oil were taken periodically just after each test, and the colors of the sampled oil compared.
2014-10-13
Technical Paper
2014-01-2836
Haichao Fu, Yinhui Wang, Xinyan Li, Shi-Jin Shuai
Abstract An experimental study of particulate matter (PM) emission was conducted on four cars from Chinese market. Three cars were powered by gasoline direct injection (GDI) engines and one car was powered by a port fuel injection (PFI) engine. Particulate mass, number and size distribution were measured based on a chassis dynamometer over new European driving cycle (NEDC). The particulate emission behaviors during cold start and hot start NEDCs were compared to understand how the running conditions influence particulate emission. Three kinds of gasoline with RON 91.9, 94.0 and 97.4 were tested to find the impact of RON on particulate emission. Because of time and facilities constraints, only one cold/hot start NEDC was conducted for every vehicle fueled with every fuel. The test results showed that more particles were emitted during cold start condition (first 200s in NEDC). Compared with cold start NEDC, the particulate mass and number of hot start NEDC decreased by a wide margin.
2014-10-13
Technical Paper
2014-01-2833
Kotaro Tanaka, Masatoshi Takano, Shuji Iimura, Kai Miyamura, Mitsuru Konno
Abstract Recently, highly sensitive near-IR laser absorption spectrometers have been employed to measure ammonia (NH3) emissions. These instruments allow in-situ measurements of highly time-resolved NH3 emission levels in automobile exhaust. However, the effect of the automobile exhaust CO2 in NH3 measurements has not been studied in detail. Because the CO2 concentration in automobile exhaust is 2 to 3 orders of magnitude higher than the NH3 concentration, there is a possibility that spectral overlap by CO2 lines and/or the spectral broadening of NH3 by CO2 could affect the measured NH3 levels. This study had two major objectives. First, the effect of CO2 on the measured NH3 concentration was assessed using our developed near-IR laser absorption spectrometer. The second objective was to provide on-board NH3 measurements in the hybrid gasoline automobile exhaust using the developed spectrometer.
2014-10-13
Technical Paper
2014-01-2810
Kihyung Joo, Jin Woo Park, Jin-ha Lee, Seok-Jae Kim, Seungbeom Yoo
Abstract In diesel engine development, the new technology is coming out to meet the stringent exhaust emission regulation. The regulation demands more eco-friendly vehicles. Euro6c demands to meet not only WLTP mode, but also RDE(Real Driving Emission). In order to satisfy RDE mode, the new technology to reduce emissions should cover all operating areas including High Load & High Speed. It is a big challenge to reduce NOx on the RDE mode and a lot of DeNOx technologies are being developed. So the new DeNOx technology is needed to cover widened operating area and strict acceleration / deacceleration. The existing LNT(Lean NOx Trap) and Urea SCR(Selective Catalytic Reduction) is necessary to meet the typical NEDC or WLTP, but the RDE mode demands the powerful DeNOx technology. Therefore, the LNT & Urea SCR on DPF was developed through this study.
2014-10-13
Technical Paper
2014-01-2811
Michal Vojtisek-Lom, Martin Pechout, Michael Fenkl
Abstract The paper focuses on portable “on-board” instrumentation and methods for evaluation of exhaust emissions from scooters and various small machinery under real-world driving conditions. Two approaches are investigated here. In one, a miniature on-board system mounted on the equipment itself performs online measurements of the concentrations of the pollutants of interest (HC, CO, CO2, NOx, some property of particulate matter), and measurement or computation of the intake air flow. This approach has been used on a 50 cm3 scooter fitted with a 14-kg on-board system and driven on local routes. Measured concentrations of gaseous compounds, particle mass and total particle length were multiplied with the corresponding intake air flow computed from measured engine rpm, intake air manifold pressure and temperature. In the second approach, a full-flow dilution tunnel, gas analyzers and particle measurement or sampling devices are mounted on an accompanying hand cart or vehicle.
2014-10-13
Technical Paper
2014-01-2808
Tao Tang, Jun Zhang, Shi-jin Shuai, Dongxiao Cao
Abstract Selective catalytic reduction (SCR) has been demonstrated as one of the most promising technologies to reduce NOx emissions from heavy-duty diesel engines. To meet the Euro VI regulations, the SCR system should achieve high NOx reduction efficiency even at low temperature. In the SCR system, NH3 is usually supplied by the injection of urea water solution (UWS), therefore it is important to improve the evaporation and decomposition efficiency of UWS at low temperature and minimize urea deposits. In this study, the UWS spray, urea decomposition, and the UWS impingement on pipe wall at low temperature were investigated based on an engine test bench and computational fluid dynamics (CFD) code. The decomposition of urea and deposits was analyzed using thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC) and fourier transform infrared spectroscopy (FTIR).
2014-10-13
Technical Paper
2014-01-2805
Benjamin Kingsbury, Jonathan Stewart, Zhentao Wu, Roy Douglas, Kang Li
Abstract This study describes an innovative monolith structure designed for applications in automotive catalysis using an advanced manufacturing approach developed at Imperial College London. The production process combines extrusion with phase inversion of a ceramic-polymer-solvent mixture in order to design highly ordered substrate micro-structures that offer improvements in performance, including reduced PGM loading, reduced catalyst ageing and reduced backpressure. This study compares the performance of the novel substrate for CO oxidation against commercially available 400 cpsi and 900 cpsi catalysts using gas concentrations and a flow rate equivalent to those experienced by a full catalyst brick when attached to a vehicle. Due to the novel micro-structure, no washcoat was required for the initial testing and 13 g/ft3 of Pd was deposited directly throughout the substrate structure in the absence of a washcoat.
Viewing 271 to 300 of 22710

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