Display:

Results

Viewing 31 to 60 of 23343
2016-10-17
Journal Article
2016-01-2287
Huifang Shao, William Lam, Joseph Remias, Joseph Roos, Seungmok Choi, HeeJe Seong
Abstract Mobile source emissions standards are becoming more stringent and particulate emissions from gasoline direct injection (GDI) engines represent a particular challenge. Gasoline particulate filter (GPF) is deemed as one possible technical solution for particulate emissions reduction. In this work, a study was conducted on eight formulations of lubricants to determine their effect on GDI engine particulate emissions and GPF performance. Accelerated ash loading tests were conducted on a 2.4L GDI engine with engine oil injection in gasoline fuel by 2%. The matrix of eight formulations was designed with changing levels of sulfated ash (SASH) level, Zinc dialkyldithiophosphates (ZDDP) level and detergent type. Comprehensive evaluations of particulates included mass, number, size distribution, composition, morphology and soot oxidation properties. GPF performance was assessed through filtration efficiency, back pressure and morphology.
2016-10-17
Journal Article
2016-01-2322
Michael Lance, Andrew Wereszczak, Todd J. Toops, Richard Ancimer, Hongmei An, Junhui Li, Leigh Rogoski, Petr Sindler, Aaron Williams, Adam Ragatz, Robert L. McCormick
This study examined the effect of Na contamination in biodiesel on the durability of a diesel emission control system consisting of DOC, DPF, and SCR components when operated with a B20 blend. Biodiesel (B100) is limited to 5 ppm alkaline (Na and K) and 5 ppm alkaline earth (Ca and Mg) metals in ASTM D6751, leading to a maximum of 1 ppm of each type of metal in a B20 blend. These limits exist to protect fuel injection equipment. The objective of this study was to determine if they adequately for protect emission control system components. An OEM production exhaust system was subjected to a simulated 435,000-mile aging on an engine test stand using B20 doped with 14 ppm Na. Hot start FTP NOx emissions rose above the certification value of 0.33 g/bhp-h half way through the test. Sequentially replacing aged DOC, DPF, and SCR devices with degreened parts and conducting hot start FTP tests showed that 65% of the NOx increase was due to DOC/DPF aging and 35% was from SCR degradation.
2016-10-17
Technical Paper
2016-01-2215
Hubertus Ulmer, Ansgar Heilig, Simon Bensch, Timo Schulteis, Jan-Kirsten Grathwol, Felix Gollmer, Christian Hofrath, Matthias Rühl
Abstract This paper focuses on the hydraulic losses of the low-pressure diesel fuel path and the impact of these losses on the fuel consumption and therefore CO2 emissions of internal combustion engines. In this context, a 1D (one-dimensional) simulation model with implemented fluid flow physics was developed. A 3D CFD model for considering complex geometries of several fuel path components further enhances the 1D approach. Experimental data from a test bench, carrying the complete fuel pressure system, were used for validations and continuous developments of the simulation models. The results show a substantial potential of the low-pressure system regarding a reduction of CO2 emissions, depending on the control strategy of the electric fuel pump and the geometrical properties of the fuel pipes and couplings. Within the New European Driving Cycle, a potential of up to 1.1 g CO2/km was observed.
2016-10-17
Journal Article
2016-01-2323
Hiroki Nakayama, Yasuharu Kanno, Makoto Nagata, Xiaolai Zheng
Abstract Reduction of the amount of platinum group metals (PGM: Pt, Pd, Rh) utilized in three-way catalysts (TWC) has been required from a point of resource shortage and cost effectiveness. A conventional TWC system is composed of a close-coupled (CC) catalyst and an underfloor (UF) catalyst, both PGM-based. The CC-TWC promotes HC/CO oxidation and NOx reduction by CO. The UF-TWC mainly facilitates further NOx reduction by CO. In this study, a TWC system comprising a CC catalyst with PGM and an UF catalyst without PGM has been described. The newly developed system, performing reasonably well with a conventional stoichiometric gasoline combustion engine, offers an opportunity to reduce PGM usage. In this system, the UF-non-PGM catalyst is composed of a Ni/CeO2 bottom layer which functions as a deNOx catalyst with CO-NO reaction and a zeolite based top layer which works as a deNOx catalyst with passive NH3-SCR reaction.
2016-10-17
Journal Article
2016-01-2330
Svitlana Kroll, E. Robert Fanick, Kristin Favela
Although the internal combustion engine has been used for more than a century, significant improvements in energy efficiency and emissions reduction are still possible. Advanced combustion strategies used to improve efficiency, emissions, and performance alter the chemical composition of engine-out emissions. Changes in exhaust chemistry affect the performance of typical exhaust aftertreatment devices used to meet tailpipe emissions standards and require new strategies and technologies for aftertreatment controls. The characterization of exhaust chemistry from advanced internal combustion engines requires a chemistry speciation and analytical system capable of measuring a wide range of compounds from raw exhaust samples. The widely accepted Auto/Oil procedure is used to quantify hydrocarbon compounds between C1 and C12 from dilute engine exhaust in Tedlar polyvinyl fluoride (PVF) bags.
2016-10-17
Journal Article
2016-01-2351
Kotaro Tanaka, Kazuki Hiroki, Tomoki Kikuchi, Mitsuru Konno, Mitsuharu Oguma
Abstract Exhaust gas recirculation (EGR) is widely used in diesel engines to reduce nitrogen oxide (NOx) emissions. However, a lacquer is formed on the EGR valve or EGR cooler due to particulate matter and other components present in diesel exhaust, causing serious problems. In this study, the mechanism of lacquer deposition is investigated using attenuated total reflection Fourier transform infrared spectrometry (ATR-FTIR) and scanning electron microscopy (SEM). Deposition of temperature-dependent lacquers was evaluated by varying the temperature of a diamond prism between 80 and 120 °C in an ATR-FTIR spectrometer integrated into a custom-built sample line, which branched off from the exhaust pipe of a diesel engine. Lacquers were deposited on the diamond prism at 100 °C or less, while no lacquer was deposited at 120 °C. Time-dependent ATR-FTIR spectra were obtained for approximately 2 h from the beginning of the experiment.
2016-10-17
Technical Paper
2016-01-2231
Aras Mirfendreski, Andreas Schmid, Michael Grill, Michael Bargende
Abstract Longitudinal models are used to evaluate different vehicle-engine concepts with respect to driving behavior and emissions. The engine is generally map-based. An explicit calculation of both fluid dynamics inside the engine air path and cylinder combustion is not considered due to long computing times. Particularly for dynamic certification cycles (WLTC, US06 etc.), dynamic engine effects severely influence the quality of results. Hence, an evaluation of transient engine behavior with map-based engine models is restricted to a certain extent. The coupling of detailed 1D-engine models is an alternative, which rapidly increases the model computation time to approximately 300 times higher than that of real time. In many technical areas, the Fourier transformation (FT) method is applied, which makes it possible to represent superimposed oscillations by their sinusoidal harmonic oscillations of different orders.
2016-10-17
Technical Paper
2016-01-2282
Toru Uenishi, Eijiro Tanaka, Takao Fukuma, Jin Kusaka, Yasuhiro Daisho
Experimental and numerical studies were conducted on diesel particulate filter (DPF) under different Particulate Matter (PM) loading and DPF regeneration conditions.Pressure losses across DPF loaded with PM having different mean particle diameters and regenerated with introducing hot gas created in Diesel Oxidation Catalyst(DOC)with oxidized hydrocarbon injected by fuel injector place on exhaust gas pipe were measured by introducing exhaust gases from a 2.2 liter inline four- cylinder, TCI diesel engine designed for use in passenger cars.Pressure drops across DPF loaded with PM having larger mean particle diameters expressed smaller than smaller mean particle diameters in PM loading phase.Meanwhile, the combustion amount and the decrease of pressure losses across DPF loaded with PM having larger mean particle diameters expressed smaller than smaller mean particle diameters in DPF regeneration phase.A mechanistic hypothesis was then proposed to explain the observed trends,accounting for the effects of the soot loading regime in the wall and the soot cake layer on the pressure drop.This hypothesis was used to guide the development and validation of a numerical model for predicting the pressure drop in the DPF.The relationship between the permeability and the porosity of the wall and soot cake layer was modeled under various soot loading conditions.The percolation coefficient at which the soot filtering regime changed from wall trapping to cake layer trapping was also determined by considering the filtering efficiency.The activation energy and exponential factor in the reaction rate constant was calibrated by each the mean diameter of secondary soot particles.The model was validated by comparing its output to the results of experimental test cell studies and used to analyze transport phenomena in particular filters.
2016-10-17
Technical Paper
2016-01-2213
Tomoaki Ito, Makoto Nagata
Diesel exhaust emission control systems often contain DOC (Diesel Oxidation Catalyst) + CSF (Catalyzed Soot Filter) components. In this system PM (particulate matter) is filtered and accumulated in the CSF and such filtered PM is periodically combusted by supplying heat to the CSF. The heat to CSF is generated within the DOC by an exothermic reaction with extra fuel supplied to the DOC. Here the exothermic performance of DOC depends on not only the active catalytic site (such as Pt and/or Pd) but also on the characteristics of the porous material supporting the precious metals. Various properties of Al2O3, i.e. pore diameter, pore volume, BET, acidity, basicity and the Ea (activation energy) of fuel combustion, used in DOCs and PGM particle size of each DOC were measured. The fuel combustion performance of each DOC was evaluated by diesel engine bench.
2016-10-17
Technical Paper
2016-01-2249
Akash Gangwar, Abhinav Bhardawaj, Ramesh Singh, Naveen Kumar
Abstract Enhancement of combustion behavior of conventional liquid fuel using nanoscale materials of different properties is an imaginative and futuristic topic. This experiment is aimed to evaluate the performance and emission characteristics of a diesel engine when lade with nanoparticles of Cu-Zn alloy. The previous work reported the effect of metal/metal oxide or heterogeneous mixture of two or more particles; less work had been taken to analyze the homogeneous mixture of metals. This paper includes fuel properties such as density, kinematic viscosity, calorific value and performance measures like brake thermal efficiency (BTE), brake specific fuel consumption (BSFC) and emission analysis of NOX, CO, CO2, HC. For the same solid concentration, nano-fuel is compared with base fuel at different engine loads; and its effect when lade at different concentrations.
2016-10-17
Technical Paper
2016-01-2256
Kristin Götz, Barbara Fey, Anja Singer, Juergen Krahl, Jürgen Bünger, Markus Knorr, Olaf Schröder
Abstract The target of the European Union (EU) from the 1990s has been to reduce the level of greenhouse gas (GHG) in the climate by 40 % by 2030 [1]. Currently the transport sector is one of the biggest greenhouse gas emission producer in the EU [2]. Drop-in biofuels can contribute to the reduction of GHG emissions in the transport sector. Diesel R33, a newly developed biofuel enables sustainable mobility fulfilling the European diesel fuel specification and reduces the GHG emissions by about 18.2 % against fossil diesel fuel. Diesel R33 is made of 7 % used cooking oil methyl ester, 26 % hydrotreated vegetable oil (HVO) and 67 % high quality diesel fuel. HVO was produced from rapeseed and palm oil. This new biofuel was tested in a fleet of 280 vehicles (passenger cars, light duty vehicles, off-road vehicles and urban buses) covering all emission classes. The impact of the new fuel on the vehicles, their emissions and the engine oil aging was investigated.
2016-10-17
Technical Paper
2016-01-2265
Ashraya Gupta, Dhruv Gupta, Naveen Kumar
Abstract The diesel engine has for many decades now assumed a leading role in both the medium and medium-large transport sector due to their high efficiency and ability to produce high torque at low RPM. Furthermore, energy diversification and petroleum independence are also required by each country. In response to this, biodiesel is being considered as a promising solution due to its high calorific value and lubricity conventional petroleum diesel. However, commercial use of biodiesel has been limited because of some drawbacks including corrosivity, instability of fuel properties, higher viscosity, etc. Biodiesel are known for lower CO, HC and PM emissions. But, on the flip side they produce higher NOx emissions. The addition of alcohol to biodiesel diesel blend can help in reducing high NOx produced by the biodiesel while improving some physical fuel properties.
2016-10-17
Technical Paper
2016-01-2284
Yuan Wen, Yinhui Wang, Chenling Fu, Wei Deng, Zhangsong Zhan, Yuhang Tang, Xuefei Li, Haichun Ding, Shijin Shuai
Abstract Gasoline Direct Injection (GDI) engines have developed rapidly in recent years driven by fuel efficiency and consumption requirements, but face challenges such as injector deposits and particulate emissions compared to Port Fuel Injection (PFI) engines. While the mechanisms of GDI injector deposits formation and that of particulate emissions have been respectively revealed well, the impact of GDI injector deposits and their relation to particulate emissions have not yet been understood very well through systematic approach to investigate vehicle emissions together with injector spray analysis. In this paper, an experimental study was conducted on a GDI vehicle produced by a Chinese Original Equipment Manufacturer (OEM) and an optical spray test bench to determine the impact of injector deposits on spray and particulate emissions.
2016-10-17
Journal Article
2016-01-2288
Sam Shamun, Mengqin Shen, Bengt Johansson, Martin Tuner, Joakim Pagels, Anders Gudmundsson, Per Tunestal
Abstract The focus has recently been directed towards the engine out soot from Diesel engines. Running an engine in PPC (Partially Premixed Combustion) mode has a proven tendency of reducing these emissions significantly. In addition to combustion strategy, several studies have suggested that using alcohol fuels aid in reducing soot emissions to ultra-low levels. This study analyzes and compares the characteristics of PM emissions from naphtha gasoline PPC, ethanol PPC, methanol PPC and methanol diffusion combustion in terms of soot mass concentration, number concentration and particle size distribution in a single cylinder Scania D13 engine, while varying the intake O2. Intake temperature and injection pressure sweeps were also conducted. The fuels emitting the highest mass concentration of particles (Micro Soot Sensor) were gasoline and methanol followed by ethanol.
2016-10-17
Journal Article
2016-01-2209
Uisung Lee, Jeongwoo Han, Michael Wang, Jacob Ward, Elliot Hicks, Dan Goodwin, Rebecca Boudreaux, Per Hanarp, Henrik Salsing, Parthav Desai, Emmanuel Varenne, Patrik Klintbom, Werner Willems, Sandra L. Winkler, Heiko Maas, Robert De Kleine, John Hansen, Tine Shim, Erik Furusjö
Abstract Dimethyl ether (DME) is an alternative to diesel fuel for use in compression-ignition engines with modified fuel systems and offers potential advantages of efficiency improvements and emission reductions. DME can be produced from natural gas (NG) or from renewable feedstocks such as landfill gas (LFG) or renewable natural gas from manure waste streams (MANR) or any other biomass. This study investigates the well-to-wheels (WTW) energy use and emissions of five DME production pathways as compared with those of petroleum gasoline and diesel using the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model developed at Argonne National Laboratory (ANL).
2016-10-17
Technical Paper
2016-01-2216
Brad Richard, Martha Christenson, Deborah Rosenblatt, Aaron Conde
Five Ford Transit Connect vans, operating on alternative fuels and propulsion systems, were tested on a chassis dynamometer. The vehicles were powered with petrol, low blend ethanol (E10), compressed natural gas (CNG), liquefied petroleum gas (LPG), and an electric battery. Four test cycles were used representing city driving and cold-start (FTP-75), aggressive high speed driving (US06), free flow highway driving (HWFCT), and a combination of urban, rural, and motorway driving (WHVC). Tests were performed at temperatures of 22°C, with select tests at -7oC and -18°C. Exhaust emissions were measured and characterized including, on all cycles, CO, NOX, THC, TPM (except on WHVC), and CO2. On the FTP-75, WHVC, and US06 cycles additional exhaust emission characterization included N2O, and CH4. On the FTP-75 and WHVC, carbonyl compounds and volatile organic compounds (VOCs) were also characterized.
2016-10-17
Technical Paper
2016-01-2283
Stephane Zinola, Stephane Raux, Mickael Leblanc
Abstract The more and more stringent regulations on particle emissions at the vehicle tailpipe have led the car manufacturers to adopt suitable emissions control systems, like particulate filters with average filtration efficiency that can exceed 99%, including particulate mass (PM) and number (PN). However, there are still some specific operating conditions that could exhibit noticeable particle number emissions. This paper aims to identify and characterize these persistent sources of PN emissions, based on tests carried out both at the engine test bench and at the chassis dynamometer, and both for Diesel and Gasoline direct injection engines and vehicles. For Diesel engines, highest particle numbers were observed downstream of the catalyzed DPF during some operation conditions like engine warm up or filter regeneration phases.
2016-10-17
Technical Paper
2016-01-2165
Kazuya Miyashita, Takamichi Tsukamoto, Yusei Fukuda, Katsufumi Kondo, Tetsuya Aizawa
Abstract For better understanding, model development and its validation of in-cylinder soot formation processes of Gasoline Direct Injection (GDI) engines, visualization of piston surface fuel wetting, vaporization and soot formation processes of in-cylinder pool fire via high-speed UV (266nm) and visible (445nm) laser shadowgraphy was attempted in an optically accessible Rapid Compression and Expansion Machine (RCEM). A direct-injection, spark-ignition and single-shot combustion event was achieved in the RCEM under engine-equivalent, simplified and well-defined conditions operated with engine speed 600 rpm, compression ratio 9.0, equivalence ratio 0.9 and natural aspiration. The tested fuel was composed of 70% iso-octane and 30% toluene by volume and the UV absorption by toluene enabled visualization of the in-cylinder fuel distribution.
2016-10-17
Journal Article
2016-01-2166
Ahfaz Ahmed, Muhammad Waqas, Nimal Naser, Eshan Singh, William Roberts, Sukho Chung, Mani Sarathy
Abstract Commercial gasoline fuels are complex mixtures of numerous hydrocarbons. Their composition differs significantly owing to several factors, source of crude oil being one of them. Because of such inconsistency in composition, there are multiple gasoline fuel compositions with similar octane ratings. It is of interest to comparatively study such fuels with similar octane ratings and different composition, and thus dissimilar physical and chemical properties. Such an investigation is required to interpret differences in combustion behavior of gasoline fuels that show similar knock characteristics in a cooperative fuel research (CFR) engine, but may behave differently in direct injection spark ignition (DISI) engines or any other engine combustion modes.
2016-10-17
Technical Paper
2016-01-2174
Reza Golzari, Yuanping Li, Hua Zhao
Abstract As the emission regulations for internal combustion engines are becoming increasingly stringent, different solutions have been researched and developed, such as dual injection systems (combined port and direct fuel injection), split injection strategies (single and multiple direct fuel injection) and different intake air devices to generate an intense in-cylinder air motion. The aim of these systems is to improve the in-cylinder mixture preparation (in terms of homogeneity and temperature) and therefore enhance the combustion, which ultimately increases thermal efficiency and fuel economy while lowering the emissions. This paper describes the effects of dual injection systems on combustion, efficiency and emissions of a downsized single cylinder gasoline direct injection spark ignited (DISI) engine. A set of experiments has been conducted with combined port fuel and late direct fuel injection strategy in order to improve the combustion process.
2016-10-17
Journal Article
2016-01-2179
Marius Zubel, Om Parkash Bhardwaj, Benedikt Heuser, Bastian Holderbaum, Sebastian Doerr, Jukka Nuottimäki
Abstract This work is a continuation of earlier results presented by the authors. In the current investigations the biofuels hydrogenated vegetable oil (HVO) and 1-octanol are investigated as pure components and compared to EN 590 Diesel. In a final step both biofuels are blended together in an appropriate ratio to tailor the fuels properties in order to obtain an optimal fuel for a clean combustion. The results of pure HVO indicate a significant reduction in CO-, HC- and combustion noise emissions at constant NOX levels. With regard to soot emissions, at higher part loads, the aromatic free, paraffinic composition of HVO showed a significant reduction compared to EN 590 petroleum Diesel fuel. But at lower loads the high cetane number leads to shorter ignition delays and therefore, ignition under richer conditions.
2016-10-17
Journal Article
2016-01-2182
Olivier Laget, Louis-Marie Malbec, Julian Kashdan, Nicolas Dronniou, Romain Boissard, Patrick Gastaldi
Abstract The accumulation of particulate matter in lubricant oil can become an important issue in Diesel engines where large amounts of Exhaust Gas Recirculation (EGR) are used at medium to high load operating conditions. Indeed, the transport and subsequent accumulation of particulate matter in the engine oil can negatively impact the oil lubricant properties which is critical to ensure mechanical durability and limit the vehicle Total Cost of Ownership (TCO) by reducing the servicing intervals. The objective of this investigation was to gain an improved understanding of the underlying mechanisms that are responsible for the accumulation of particulate matter in the lubricating oil, and ultimately provide design guidelines to help limit this phenomenon. The present study presents the development and validation of experimental and numerical tools used to investigate this phenomenon.
2016-10-17
Technical Paper
2016-01-2181
Yong Qian, Yahui Zhang, Liang Yu, Zhen Huang, Xing-Cai Lu
Abstract In this paper, an experimental study has been conducted to study the effects of iso-alkanes blending in diesel on combustion and emission characters based on a modified single cylinder diesel engine. Iso-octane, iso-dodecane and 2,2,4,4,6,8,8-heptamethylnonane (HMN) were chosen as test iso-alkanes. The direct injection timing was kept at 7 oCA BTDC. The injection pressure was maintained at 120 MPa. The study found that iso-alkanes had strong effects on the heat release phase under low load. The effects were weakened gradually with the increase of loads. The peak value of heat release curves and the maximum pressure rising rate gradually increased with the increase of loads. Blending iso-alkanes resulted in the increase of CO emissions and decrease of HC emissions. NOx emissions also decrease under low loads. Under high loads, blending iso-alkanes reduced the soot emissions significantly.
2016-10-17
Technical Paper
2016-01-2184
Manuel A. Gonzalez D, Davide Di Nunno
Abstract The application of stringent requirements on emission reduction and higher fuel economy in diesel engines has led to the need for efficient energy extraction in the cylinders and reductions in exhaust gas temperatures, as well as posing challenges for energy availability for emission control systems. Internal exhaust gas recirculation (I-EGR) can increase the exhaust gas temperature and reduce engine-out gaseous emissions. The secondary opening of exhaust valves in a diesel engine produces an efficient recirculation of exhaust gases from the previous engine cycle to the cylinder mass charge during the intake stroke. However, I-EGR alone can increase exhaust gas temperature only up to a limit determined by the resulting increase in soot emissions. To obtain higher exhaust gas temperatures, I-EGR can be combined with multiple injections after the main injection event, thereby altering the heat release rate and the exothermic reactions in the exhaust stroke.
2016-10-17
Journal Article
2016-01-2183
Yann Gallo, Zheming Li, Mattias Richter, Oivind Andersson
Abstract Soot emissions from diesel engines are the net result of two competing processes: soot formation and soot oxidation. Previous studies have shown poor correlation between soot formation rates and the soot emissions. This article presents a systematic study of a number of parameters affecting soot oxidation rate and how it correlates with the soot emissions. An optical heavy-duty engine is used in conjunction with a laser extinction setup in order to collect time resolved data of the soot concentration in the cylinder during the expansion stroke. Laser extinction is measured using a red (685 nm) laser beam, which is sent vertically through the cylinder and modulated to produce 10 pulses per crank angle degree. Information is obtained about the amount of soot formed and the soot oxidation rate. The parameters studied are the motored density at top dead center (TDC), motored temperature at TDC, injection pressure, engine speed, swirl level and injector orifice diameter.
2016-10-17
Technical Paper
2016-01-2187
Haifeng Liu, Huixiang Zhang, Hu Wang, Xian Zou, Mingfa Yao
Abstract The combustion in low-speed two-stroke marine diesel engines can be characterized as large spatial and temporal scales combustion. One of the most effective measures to reduce NOx emissions is to reduce the local maximum combustion temperature. In the current study, multi-dimensional numerical simulations have been conducted to explore the potential of Miller cycle, high compression ratio coupled with EGR (Exhaust Gas Recirculation) and WEF (water emulsified fuel) to improve the trade-off relationship of NOx-ISFC (indicated specific fuel consumption) in a low-speed two-stroke marine engine. The results show that the EGR ratio could be reduced combined with WEF to meet the Tier III emission regulation. The penalty on fuel consumption with EGR and WEF could be offset by Miller cycle and high geometric compression ratio.
2016-10-17
Technical Paper
2016-01-2185
Jialin Liu, Hu Wang, Zunqing Zheng, Zeyu Zou, Mingfa Yao
Abstract In this work, both the ‘SCR-only’ and ‘EGR+SCR’ technical routes are compared and evaluated after the optimizations of both injection strategy and turbocharging system over the World Harmonized Stationary Cycle (WHSC) in a heavy duty diesel engine. The exhaust emissions and fuel economy performance of different turbocharging systems, including wastegate turbocharger (WGT), variable geometry turbocharger (VGT), two-stage fixed geometry turbocharger (WGT+FGT) and two-stage variable geometry turbocharger (VGT+FGT), are investigated over a wide EGR range. The NOx reduction methods and EGR introduction strategies for different turbocharger systems are proposed to improve the fuel economy. The requirement on turbocharging system and their potential to meet future stringent NOx and soot emission regulations are also discussed in this paper.
2016-10-17
Technical Paper
2016-01-2169
Carrie M. Hall, James Sevik, Michael Pamminger, Thomas Wallner
Abstract The high octane rating and more plentiful domestic supply of natural gas make it an excellent alternative to gasoline. Recent studies have shown that using natural gas in dual fuel engines provides one possible strategy for leveraging the advantages of both natural gas and gasoline. In particular, such engines been able to improve overall engine efficiencies and load capacity when they leverage direct injection of the natural gas fuel. While the benefits of these engine concepts are still being explored, differences in fuel composition, combustion process and in-cylinder mixing could lead to dramatically different emissions which can substantially impact the effectiveness of the engine’s exhaust aftertreatment system. In order to explore this topic, this study examined the variations in speciated hydrocarbon emissions which occur for different fuel blends of E10 and compressed natural gas and for different fuel injection strategies on a spark-ignition engine.
2016-10-17
Technical Paper
2016-01-2172
Matthieu Cordier, Olivier Laget, Florence Duffour, Xavier Gautrot, Loic De Francqueville
Abstract Increasing global efficiency of direct injection spark ignition (DISI) engine is nowadays one of the main concerns in automotive research. A conventional way to reduce DISI engine fuel consumption is through downsizing. This approach is well suited to the current homologation cycle as NEDC, but has the drawback to induce over-consumptions in customer real driving usage. Moreover, the driving cycles dedicated to EURO 6d and future regulations will evolve towards higher load operating conditions with higher particulate emissions. Therefore, efficiency of current DISI has to be strongly increased, for homologation cycle and real driving conditions. This implies to deeply understand and improve injection, mixing and flame propagation processes.
2016-10-17
Journal Article
2016-01-2208
Zifeng Lu, Jeongwoo Han, Michael Wang, Hao Cai, Pingping Sun, David Dieffenthaler, Victor Gordillo, Jean-Christophe Monfort, Xin He, Steven Przesmitzki
Abstract Gasoline Compression Ignition (GCI) engines using a low octane gasoline-like fuel (LOF) have good potential to achieve lower NOx and lower particulate matter emissions with higher fuel efficiency compared to the modern diesel compression ignition (CI) engines. In this work, we conduct a well-to-wheels (WTW) analysis of the greenhouse gas (GHG) emissions and energy use of the potential LOF GCI vehicle technology. A detailed linear programming (LP) model of the US Petroleum Administration for Defense District Region (PADD) III refinery system - which produces more than 50% of the US refined products - is modified to simulate the production of the LOF in petroleum refineries and provide product-specific energy efficiencies. Results show that the introduction of the LOF production in refineries reduces the throughput of the catalytic reforming unit and thus increases the refinery profit margins.
Viewing 31 to 60 of 23343

Filter