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2015-06-15 ...
  • June 15-17, 2015 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
Liquid fuel atomization and spray formation is the heart of the majority of stationary and mobile power generation machines that we rely on. This seminar focuses on the process of liquid atomization and spray formation and how it relates to fuel injection systems and emission of pollutants in modern engines. The seminar begins with background coverage of terminology, the purposes of liquid atomization and spray formation, and different designs of atomizers and nozzles employed in various industries.
2015-06-03 ...
  • June 3-5, 2015 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
Fuel composition has had to change with the advent of more stringent emission regulations. Reformulated gasoline (RFG), for example, is vastly different from gasoline of even ten years ago. Tightening regulations on diesel emissions will dramatically change both diesel fuel and engine design. This three-day seminar will review the fundamentals of motor fuels, combustion and motor power generation. The primary content of the course provides a basic introduction to the technology, performance, evaluation, and specifications of current gasoline, diesel, and turbine fuels.
2015-04-22
Event
This session focuses on abnormal SI combustion processes including spark knock and preignition. Papers cover both 4-stroke and 2-stroke engines characterized by 1) ignition by an external energy source that serves to control combustion phasing, and 2) a combustion rate that is limited by flame propagation. Part 1 of 2: Knock
2015-04-22
Event
This session focuses on abnormal SI combustion processes including spark knock and preignition. Papers cover both 4-stroke and 2-stroke engines characterized by 1) ignition by an external energy source that serves to control combustion phasing, and 2) a combustion rate that is limited by flame propagation. Part 2 of 2: Low-Speed Preignition
2015-04-22
Event
This session focuses on fuel injection, combustion, controls, performance and emissions of SI engines fueled with gaseous fuels such as methane, natural gas (NG), biogas, producer gas, coke oven gas, hydrogen, or hydrogen-NG blends. Papers on Diesel-NG or diesel-hydrogen dual-fuel engines will also be accepted in this session.
2015-04-14
Technical Paper
2015-01-0833
Buyu Wang, Zhi Wang, Shi-Jin Shuai, Jian-Xin Wang
A study of Multiple Premixed Compression Ignition (MPCI) with mixtures of gasoline and diesel is performed on a light-duty single cylinder diesel engine. The engine is operated at a speed of 1600rpm with the same fueling rate for different gasoline and diesel mixtures. By keeping the same intake pressure and EGR ratio, the influence of different blending ratios in gasoline and diesel mixtures are investigated. Commercial diesel is also tested as a reference. Combustion and emissions characteristics are compared by sweeping the first (-95 ~ --35 deg ATDC) and the second injection timing (-1 ~ 9 deg ATDC) with an injection split ratio of 82/18 and an injection pressure of 80MPa. The results show that compared with diesel combustion, the gasoline and diesel mixtures can reduce NOx and soot emissions simultaneously while maintaining or achieving even higher indicated thermal efficiency, but the HC and CO emissions are higher for the mixtures.
2015-04-14
Technical Paper
2015-01-0848
Silvana Di Iorio, Paolo Sementa, Bianca Maria Vaglieco
Gasoline direct injection (GDI) is a cost-effective option for improving the efficiency and performance of gasoline engines. Nevertheless, particulate emission are larger than conventional port fuel injection (PFI) engines. Ethanol is very effective in particle emissions reduction. On the other hand, the low vapor pressure of ethanol makes cold start very difficult, and the low lower heating value (LHV) results in lower energy density and then larger fuel consumption. The dual-fuel injection system can be used to improve the engine performance and reduce the fossil fuel consumption performing simultaneously a direct-injection (DI) and a port-fuel-injection (PFI) of different fuels. The aim of the paper is the investigation of the particle emissions from ethanol-gasoline dual fuel combustion. The engine was operated also in gasoline-gasoline dual fuel mode to distinguish the effect of injection strategy from the effect of fuel.
2015-04-14
Technical Paper
2015-01-1242
Hao Yuan, Tien Mun Foong, Zhongyuan Chen, Yi Yang, Michael Brear, Thomas Leone, James E. Anderson
Ethanol has demonstrated strong, anti-knock performance in spark ignition (SI) engines, and this is one important reason for its increasing use around the world. Ethanol’s high octane rating is attributed to both its low autoignition reactivity and high charge cooling capability. Further, whilst detailed chemical kinetic mechanisms have been developed for gasoline surrogates and ethanol, little work has been done to investigate whether autoignition in modern, SI engines with ethanol/gasoline blends can be reproduced by these mechanisms, in particular for cases with direct fuel injection. This paper therefore presents a numerical study of the trace knocking of ethanol/gasoline blends in a modern, single cylinder SI engine. Results of these numerical simulations are compared to experimental results obtained in a prior, published work [1]. The engine is modeled using GT-Power and a two-zone combustion model.
2015-04-14
Technical Paper
2015-01-1082
Xin Wang, Yunshan Ge, Linlin Liu, Huiming Gong
As a cheap, clean alternative, neat methanol and methanol gasoline are widely used as vehicle fuel in many provinces in China. Though burning methanol is able to curb carbonaceous pollutants from engine, NOx and carbonyls, in particular formaldehyde, remain concerns over atmospheric environment and public health. In this paper, regulated, carbonyl emissions together with particulate matter from a neat methanol/gasoline dual-fuel passenger car were examined over New European Driving Cycle (NEDC). The results yielded that, CO, HC and NOx from different fuel regimes were very similar. 14 kinds of carbonyl compounds in the exhaust samples were analyzed. In comparison with gasoline baseline, approximately 41.9% more carbonyls, majority of which were formaldehyde, acetaldehyde, propyl aldehyde and benzaldehyde, were discharged by methanol fuelling. Regarding particulate matter, a remarkable decrease of 63% in mass was obtained by fuelling with methanol.
2015-04-14
Technical Paper
2015-01-0767
Richard Stradling, David Rickeard, Heather Hamje, John Williams, Peter Zemroch
Gasoline combustion has traditionally been measured using Research Octane Number (RON) and Motor Octane Number (MON) which describe antiknock performance under different conditions. Recent literature suggests that MON is less important than RON in modern cars and a relaxation in the MON specification could improve vehicle performance, while also helping refiners in the production of gasoline. At the same time, for the same octane number change, increasing RON appears to provide more benefit to engine power and acceleration than reducing MON. It has also been suggested that there could be fuel efficiency benefits (on a tank to wheels basis) for specially adapted engines, for example, operating at higher compression ratio, on very high RON (100+). Other workers have advocated the use of an octane index (OI) which incorporates both parameters instead of either RON or MON to give an indication of octane quality.
2015-04-14
Technical Paper
2015-01-1011
Kazutake Ogyu, Toyoki Ogasawara, Yuichi Nagatsu, Yuya Yamamoto, Tatsuhiro Higuchi, Kazushige Ohno
The Particle Number (PN) emission limit is implemented for Direct Injection (DI) gasoline from Euro6 regulation in European region. The wall-flow type ceramic filter technology is an essential component for Diesel PN emission control, and will be one potential solution to be investigated for the future Gasoline DI PN emission control demand. Especially the requirement of lower pressure loss with smaller filter volume is very strong for the filter substrate for Gasoline DI compared to DPF, not to lose better fuel economy benefit of Gasoline DI engine. Re-crystallized SiC (R-SiC) has high strength as its own property, and enable for Gasoline Particulate Filter (GPF) design to make the wall thickness thinner and the porosity higher compared to the other ceramic materials.
2015-04-14
Journal Article
2015-01-1245
Darko Kozarac, Rudolf Tomic, Ivan Taritas, Jyh-Yuan Chen, Robert W. Dibble
Development of SI engines and further increase of engine efficiency is strongly affected by the occurrence of knock. Knock has been widely investigated over the years and the main promoting parameters have been identified as load (temperature and pressure), mixture composition, engine speed, characteristic of the fuel, combustion chamber design, etc. On the other hand recent engine developments heavily depend on engine modeling that ranges from detail modeling for fundamental insights to much simpler modeling that can be used in the optimization of engine operating conditions. In this paper the new model for predicting knock in 0-D environment is presented. The model is based on the well known approach of using a Livengood and Wu knock integral. Ignition delay data that are supplied to the knock integral are for specific fuel calculated by detail chemical kinetics and are comprised of low temperature heat release ignition delay and high temperature heat release ignition delay.
2015-04-14
Technical Paper
2015-01-0827
Yan Zhang, Macklini Dalla Nora, Hua Zhao
Controlled Auto Ignition (CAI), also known as Homogeneous Charge Compression Ignition (HCCI), is one of the most promising combustion technologies to reduce the fuel consumption and NOx emissions. In order to extend its currently limited operational range and meet the demand of whole vehicle driving cycles, the authors have transplanted it back in a 2-stroke engine with poppet valve train, where the output torque is doubled compared to that of 4-stroke engines. Due to the air short-circuiting issue on 2-stroke engines, the lean boost operation has been implemented with CAI combustion under a speed range from 800rpm to 3000rpm and an IMEP range from 1.1bar to 7.8bar. In this work, to further extend the operational range, ethanol-gasoline blends, E85 were tested with 2-stroke lean boost operation. The results show that CAI high load knocking limit is extended because of the charge cooling effect and slower burning rate of ethanol.
2015-04-14
Technical Paper
2015-01-1076
Tak W. Chan
Octane number is an indication of the antiknocking strength of gasoline and it is strongly linked to engine performance which has direct influence on vehicle black carbon (BC) and ultrafine particle emissions. In the past, additives such as tetra-ethyl lead (TEL) were used as antiknocking fuel additives, but were phased out due to environmental and human health issues. More recently, other options such as butane, aromatics, and different oxygenates (i.e., alcohols and ethers) have been used to increase the knock resistance of gasoline. Ethanol is one of the most commonly used alcohols to increase the antiknocking resistance of gasoline. When used in internal combustion engines, ethanol-gasoline fuel provides a number of direct advantages such as antiknocking, reduced CO emissions, high Reid vapor pressure, and charge air cooling.
2015-04-14
Technical Paper
2015-01-0942
Vikram Singh, Anshul Koli
Abstract This research presents the simulation of the jet behavior of gasoline ethanol blends in a quiescent chamber using the Lattice Boltzmann method. The fuel is taken as different mixtures of gasoline and ethanol, and the properties, such as density, viscosity and surface tension, are varied accordingly in the Lattice Boltzmann model. The variations in jet structure and instabilities are modeled according to the velocity of fuel injection, the composition of the gasoline-ethanol blend and the property of the surrounding mixture. The model implemented for the interaction of the two fluids; air and fuel, is the Shan Chen model. The accuracy of the model is confirmed using a static drop test at different curvatures for the two fluids as well as observing the evolution of merging droplets. This is the first time that the study of different fuels in done using the Shan Chen model.
2015-04-14
Journal Article
2015-01-0744
Terrence Alger, Raphael Gukelberger, Jess Gingrich, Barrett Mangold
The use of cooled EGR as a knock suppression tool is gaining more acceptance worldwide. As cooled EGR become more prevelant, some challenges are presented for engine designers. In this study, the impact of cooled EGR on peak cylinder pressure was evaluated. A 1.6 L, 4-cylinder engine was operated with and without cooled EGR at several operating conditions. The impact of adding cooled EGR to the engine on peak cylinder pressure was then evaluated with an attempt to separate the effect due to advanced combustion phasing from the effect of increased manifold pressure. The results show that cooled EGR's impact on peak cylinder pressure is solely due to the knock suppression effect, with the result that an EGR rate of 25% leads to an almost 50% increase in peak cylinder pressure at a mid-load condition. When combustion phasing was held constant, increasing the EGR rate had no effect on PCP.
2015-04-14
Technical Paper
2015-01-0750
Shinrak Park, Tetsuji Furukawa
Downsizing or higher compression ratio of SI engines is an appropriate way to achieve considerable improvements of part load fuel efficiency. As the compression ratio directly impacts the thermal efficiency, it is consequential to raise it as well in order to maximize the fuel consumption gain. However, when operating a highly boosted / downsized SI engine at full load, the actual combustion process deviates strongly from the ideal Otto cycle due to the fact that particularly the high downsizing grade and increased compression ratio lead to the necessity of delayed ignition timing to avoid abnormal combustion phenomena, especially knocking. This means that there is a trade-off for the optimal design of an SI engine between part load and full load operation. If the characteristic of a knocking can be beforehand predicted accurately when designing a combustion chamber, the further shortening time of design or increase in efficiency of development would be possible.
2015-04-14
Journal Article
2015-01-0763
Gina M. Chupka, Earl Christensen, Lisa Fouts, Teresa L. Alleman, Matthew A. Ratcliff, Robert L. McCormick
The objective of this work was to measure knock resistance metrics for ethanol-hydrocarbon blends with a primary focus on development of methods to measure the heat of vaporization (HOV). Blends of ethanol at 10 to 50 volume percent were prepared with three gasoline blendstocks and a natural gasoline. Performance properties and composition of the blendstocks and blends were measured, including research octane number (RON), motor octane number (MON), net heating value, density, distillation curve, and vapor pressure. RON increases upon blending ethanol but with diminishing returns above about 30 vol%. Above 30% to 40% ethanol the curves flatten and converge at a RON of about 103 to 105, even for the much lower RON NG blendstock. Octane sensitivity (S = RON – MON) also increases upon ethanol blending. Gasoline blendstocks with nearly identical S can show significantly different sensitivities when blended with ethanol.
2015-04-14
Journal Article
2015-01-0894
Michael D. Kass, Chris Janke, Timothy Theiss, James Baustian, Leslie Wolf, Wolf Koch
Plastic materials are used ubiquitously in fuel infrastructure systems. A matrix of plastic specimens including thermoplastics and thermosetting resins were exposed to test fuels representing neat gasoline and E10. Previously the research team had evaluated plastic materials in test fuels representing E0, E25, E50, and E85. The lack of information for a 10 percent ethanol blend has prevented accurate interpolation of performance of these materials at low blend levels. The test fuel was an aggressive formulation derived following the SAE J1681 protocol. Four specimens were evaluated for each material type (three immersed in the test fuel liquid and one placed exposed to the vapor phase only). For each specimen exposed to the liquid fuel, the mass and volume change and hardness were measured for both wetted and dried conditions. The specimens exposed to the vapor phase were measured for hardness only.
2015-04-14
Technical Paper
2015-01-0752
Zhi Wang, Yunliang Qi, Hui Liu, Yan Long, Jian-Xin Wang
Occurrence of sporadic super-knock is the main obstacle to the development of advanced gasoline engines. One of the possible inducements of super-knock, agglomerated soot particle induced pre-ignition, was proposed for high boosted gasoline direct injection (GDI) engines. The correlation between soot emissions and super-knock frequency was investigated in a four-cylinder gasoline direct injection production engine. The test results indicate that higher in-cylinder soot emission correlate with more pre-ignition and super-knock cycles in a GDI production engine. To validate the hypothesis – in-cylinder soot particles trigger super-knock, a single-cylinder research engine for super-knock study was developed. The carbon particles with different temperatures and sizes were introduced into the combustion chamber to trigger pre-ignition and super-knock.
2015-04-14
Technical Paper
2015-01-0760
Sabino Luisi, Vittorio Doria, Andrea Stroppiana, Federico Millo, Mohsen Mirzaeian
The application of Miller cycle through Late Intake Valve Closure (LIVC) or Early Intake Valve Closure (EIVC) for knock mitigation at high load on a turbocharged downsized spark ignition engine was experimentally investigated. By reducing the effective compression ratio due to a shorter compression stroke and hence achieving lower charge temperatures inside the cylinder, significant mitigation of knock tendency could be obtained, thus allowing the adoption of more advanced spark timings and the achievement of lower exhaust temperatures. As a consequence, the enrichment of the mixture could significantly be reduced, thus obtaining impressive efficiency improvements. Although the effective compression ratio could be controlled by using both EIVC and LIVC , the former inherently reduces the level of turbulence in the cylinder and may cause poor fuel-air mixing, while the latter generally shows a less negative impact on turbulence and mixture formation.
2015-04-14
Technical Paper
2015-01-0764
Seokwon Cho, Namho Kim, Jongwon Chung
Ethanol is becoming more popular as a fuel for spark-ignited engines. Ethanol can be used as either octane enhancer of low RON gasoline, or splash-blended with gasoline if single injector is used for fuel injection. If two separate injectors can be used, it is possible to inject gasoline and ethanol respectively, addition of ethanol can be varied on demand. In this study, the effect of ethanol injection strategy on knock suppression was observed using a single cylinder engine equipped with two port fuel injectors dedicated to each side of intake port and one direct injection injector. If the fuel is injected to only one side of the intake port, it is possible to form stratified charge. The experiment was conducted under compression ratio of 12.2 under the various injection strategies.
2015-04-14
Journal Article
2015-01-1622
Nicolo Cavina, Andrea Businaro, Giorgio Mancini, Matteo De Cesare, Federico Covassin, Stefano Sgatti
In the field of passenger car engines, recent research advances have proven the effectiveness of downsized, turbocharged and direct injection concepts, applied to gasoline combustion systems, to reduce the overall fuel consumption while respecting particularly stringent exhaust emissions limits. Knock and turbocharger control are two of the most critical factors that influence the achievement of maximum efficiency and satisfactory drivability, for this new generation of engines. The sound emitted from an engine encloses many information related to its operating condition. In particular, the turbocharger whistle and the knock clink are unmistakable sounds. This paper presents the development of real-time control functions, based on direct measurement of the engine acoustic emission, able to provide information about turbocharger speed and knock intensity.
2015-04-14
Journal Article
2015-01-0397
Francesco Catapano, Michela Costa, Guido Marseglia, Paolo Sementa, Ugo Sorge, Bianca Maria Vaglieco
This paper deals with a comprehensive analysis of knock through experiments and numerical simulations. Conventional and non-conventional measurements were performed in a 4-stroke, 4-cylinder, turbocharged DISI engine. Imaging and natural emission spectroscopic measurements in UV–visible range were carried out by means of a high spatial and temporal resolution camera in the combustion chamber of the engine, through an endoscopic system and a transparent window located in the piston head. Different engine conditions obtained changing the Start of Spark (SOS) and the intake pressure at 1500 rpm high load were tested, in order to obtain different levels of knock. The optical data were correlated to the in-cylinder pressure-based indicated analysis, to the exhaust emissions and to the ionization and accelerometer signals.
2015-04-14
Journal Article
2015-01-0781
Raphael Gukelberger, Jess Gingrich, Terrence Alger, Steven Almaraz
The ongoing pursuit of improved engine efficiency and emissions is driving gasoline low-pressure loop EGR systems into production around the globe. To minimize inevitable downsides of cooled EGR while maintaining its advantages, the Dedicated EGR (D-EGR®) engine was invented. The D-EGR engine is a patented, cost-effective, high efficiency, low emissions internal combustion engine for automotive and off-highway applications. The core of the engine development focused on a unique concept that combines the efficiency improvements associated with recirculated exhaust gas and the efficiency improvements associated with fuel reformation. To outline the differences of the new engine concept with a conventional LPL EGR setup, a turbocharged 2.0 L PFI engine was modified to operate in both modes. The second part of the cooled EGR engine concept comparison investigates efficiency, knock resistance, combustion stability, and maximum load potential at un-throttled conditions.
2015-04-14
Journal Article
2015-01-0813
John E. Dec, Yi Yang, Jeremie Dernotte, Chunsheng Ji
Responding to the need to reduce petroleum consumption, gasoline in the U.S. now contains 10% ethanol (E10), and levels of 15% and 20% (E20) are being considered. Petroleum consumption can also be reduced by improving engine efficiency, and engines using low-temperature gasoline combustion (LTGC), which includes HCCI and partially stratified variants of HCCI, align with this goal. Adding ethanol changes the autoignition characteristics of gasoline, and it is important to understand how this affects the performance of premixed LTGC (i.e. HCCI) and the potential to use advanced techniques such as partial fuel stratification (PFS) that can improve the efficiency and load range of intake-boosted LTGC. Accordingly, a study was conducted comparing the performance of conventional petroleum-based gasoline (E0) with E10 and E20 for both premixed and PFS LTGC. The E10 and E20 were obtained by blending pure ethanol with the E0 (AKI=87) gasoline.
2015-04-14
Journal Article
2015-01-0855
Adam B. Dempsey, Scott Curran, Rolf D. Reitz
The focus of the present study was to characterize Reactivity Controlled Compression Ignition (RCCI) using a single-fuel approach of gasoline and gasoline mixed with a commercially available cetane improver on a multi-cylinder engine. RCCI was achieved by port injecting a certification grade 96 research octane gasoline and direct injecting the same gasoline mixed with various levels of the cetane improver, 2-ethylhexyl nitrate (EHN). The EHN volume percentage in the direct injected fuel was 10%, 5%, and 2.5%. The engine performance and emissions of the different fueling combinations was characterized at 2300 rpm and 4.2 bar BMEP over a various parametric investigations. Comparisons were made to gasoline/diesel operation on the same engine platform. The experiments were conducted on a four cylinder General Motors 1.9L ZDTH engine that has been modified with a port-fuel injection system while maintaining the stock direct injection fuel system.
2015-04-14
Journal Article
2015-01-0871
James C. Peyton Jones, Jesse Frey
Knock thresholds are typically set such that only a small fraction of high intensity knocking cycles classify as knock events under BorderLine (BL) knock spark advance conditions. Recent work, however, suggests that lowering the knock threshold and controlling to a higher 'weak knock' rate target provides more informative feedback on differences in the underlying knock intensity distribution and results in improved closed loop knock control. However, in this prior work, a rather ad-hoc method was used to optimize the thresholds. In this paper a more rigorous approach is adopted which seeks to place the threshold so as to minimize the misclassification error of knocking / non-knocking cycles. This procedure is applicable to all knock event-based controllers, but is illustrated on a classical slow-advance, fast-retard knock controller. A second, and equally important contribution of the paper, concerns the performance evaluation of the resulting control strategy.
2015-04-14
Journal Article
2015-01-1244
Luigi Teodosio, Vincenzo De Bellis, Fabio Bozza
It is well known that the downsizing allows to improve the brake specific fuel consumption (BSFC) at part load operations for the spark ignition engines. On the other hand, the BSFC is penalized at high/full load operations because of the knock occurrence and of some limitations for the turbine inlet temperature. In fact, these drawbacks obligate to adopt a late phasing of the combustion process and an enrichment of air/fuel mixture, with a substantial detriment of the fuel economy. In this work, a downsized twin-cylinders turbocharged engine is analyzed by means of a 1D numerical approach. In a first stage, the 1D engine model is tuned against the experimental data at full load operations. A refined knock model is proposed, that is based on a detailed description of the chemical kinetics in the “end gas”. The model is validated through the identification of the knock-limited spark advance, denoting a very satisfactory agreement with the experimentally-identified spark timing.
2015-04-14
Technical Paper
2015-01-0924
Joseph Camm, Richard Stone, Martin Davy, David Richardson
A model for the evaporation of a multi-component fuel droplet is presented that takes account of temperature dependent fuel and vapour properties, evolving droplet internal temperature distribution and composition, and enhancement to heat and mass transfer due to droplet motion. The effect on the internal droplet mixing of non-ideal fluid diffusion is accounted for. Activity coefficients for vapour-liquid equilibrium and diffusion coefficients are determined using the UNIFAC method. Both well-mixed droplet evaporation (assuming infinite liquid mass diffusivity) and liquid diffusion-controlled droplet evaporation (iteratively solving the multi-component diffusion equation) have been considered.
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