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2017-12-18 ...
  • December 18-20, 2017 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
Public awareness regarding pollutants and their adverse health effects has created an urgent need for engineers to better understand the combustion process as well as the pollutants formed as by-products of that process. To effectively contribute to emission control strategies and design and develop emission control systems and components, a good understanding of the physical and mathematical principles of the combustion process is necessary. This seminar will bring issues related to combustion and emissions "down to earth," relying less on mathematical terms and more on physical explanations and analogies.
2017-10-06 ...
  • October 6, 2017 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
Designing more efficient and robust emission control components and exhaust systems results in more efficient performance, reduced backpressure and fuel penalty, and higher conversion efficiency. This course will help you to understand the motion of exhaust flow in both gasoline and diesel emission control components including flow-through and wall-flow devices such as catalytic converters, NOx adsorbers, diesel oxidation catalysts, diesel particulate filters as well as flow through the overall exhaust system.
2017-09-11 ...
  • September 11-12, 2017 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
Meeting the requirements of heavy-duty engine emissions regulations is a challenge for all engine manufacturers. Since the introduction of Exhaust Gas Recirculation (EGR) in medium and heavy-duty diesel engines, these systems have become more sophisticated and tightly integrated with emission control systems. This 2-day seminar will explore the advantages and disadvantages of EGR and the most effective implementation of various EGR systems. This seminar will begin by defining EGR and why it is used in diesel engines, along with an explanation of the mechanisms by which EGR is able to reduce NOx.
2017-09-04
Technical Paper
2017-24-0057
Roberto Finesso, Omar Marello, Ezio Spessa, Yixin Yang, Gilles Hardy
A model-based control of BMEP (Brake Mean Effective Pressure) and NOx emissions has been developed and assessed for a Euro VI 3.0L diesel engine for heavy-duty applications. The control is based on a zero-dimensional real-time combustion model, which is capable of simulating the HRR (heat release rate), in-cylinder pressure, brake torque, exhaust gas temperatures, NOx and soot engine-out levels. The real-time combustion model has been realized by integrating and improving previously developed simulation tools. The chemical energy release has been simulated using the accumulated fuel mass approach. The in-cylinder pressure was estimated on the basis of a single-zone heat release model, using the net energy release as input. The latter quantity was obtained starting from the simulated chemical energy release, and evaluating the heat transfer of the charge with the walls.
2017-09-04
Technical Paper
2017-24-0046
Richard Stone, Ben Williams, Paul Ewart
The increased efficiency and specific output with Gasoline Direct Injection (GDI) engines are well known, but so too are the higher levels of Particulate Matter emissions compared with Port Fuel Injection (PFI) engines. To minimise Particulate Matter emissions, then it is necessary to understand and control the mixture preparation process, and important insights into GDI engine combustion can be obtained from optical access engines. Such data is crucial for validating models that predict flows, sprays and air fuel ratio distributions. Mie scattering can be used for semi-quantitative measurements of the fuel spray and this can be followed with Planar Laser Induced Fluorescence (PLIF) for determining the air fuel ratio and temperature distributions. With PLIF, very careful in-situ calibration is needed, and for temperature this can be provided by Laser Induced Thermal Grating Spectroscopy (LITGS).
2017-09-04
Technical Paper
2017-24-0048
Jose V. Pastor, Jose M. Garcia-Oliver, Antonio Garcia, Mattia Pinotti
In the past few years various studies have shown how the application of a highly premixed dual fuel combustion for CI engines leads a strong reduction for both pollutant emissions and fuel consumption. In particular a drastic soot and NOx reduction were achieved. In spite of the most common strategy for dual fueling has been represented by using two different injection systems, various authors are considering the advantages of using a single injection system to directly inject blends in the chamber. In this scenario, a characterization of the behavior of such dual-fuel blend spray became necessary, both in terms of inert and reactive ambient conditions. In this work, a light extinction imaging (LEI) has been performed in order to obtain two-dimensional soot distribution information within a spray flame of different diesel/gasoline commercial fuel blends. All the measurements were conducted in an optically accessible two-stroke engine equipped with a single-hole injector.
2017-09-04
Technical Paper
2017-24-0051
Ferdinando Taglialatela, Mario Lavorgna, Silvana Di Iorio, Ezio Mancaruso, Bianca Maria Vaglieco
Real time estimation of particle size distribution has a great importance for advanced control strategies that can allow diesel engines to comply with future emission standards. Moreover, knowledge of real time particulate size distribution allows the optimization of the functioning of after-treatment systems. The aim of this paper is to present a Neural Network model able to provide real time information about the characteristics of particulate emissions from a Diesel engine. The model has as inputs some engine parameters such as engine speed, engine load, EGR ratio, etc., and, as output, the particle size distribution. Preliminary results indicated that the model shows, for every engine operating condition, a satisfactory capability of estimating the concentrations of particulate particles with prefixed diameters.
2017-09-04
Technical Paper
2017-24-0027
Nearchos Stylianidis, Ulugbek Azimov, Nobuyuki Kawahara, Eiji Tomita
A chemical kinetics and computational fluid-dynamics (CFD) analysis were performed to evaluate the combustion of syngas derived from biomass and coke-oven solid feedstock in a micro-pilot ignited supercharged dual-fuel engine under lean conditions. For this analysis, a new reduced syngas chemical kinetics mechanism was constructed and validated by comparing the ignition delay and laminar flame speed data with those obtained from experiments and other detail chemical kinetics analysis available in the literature. The reaction sensitivity analysis was conducted for ignition delay at elevated pressures in order to identify important chemical reactions that govern the combustion process. We found that HO2+OH=H2O+O2 and H2O2+H=H2+HO2 reactions showed very high sensitivity during high-pressure ignition delay times and had considerable uncertainty.
2017-09-04
Technical Paper
2017-24-0022
Alessio Dulbecco, Gregory Font
Diesel engine pollutant emissions legislation is becoming more and more stringent. New driving cycles, including increasingly more severe transient engine operating conditions and low temperature ambient conditions, extend considerably the engine operating domain to be optimized to attain the expected engine performance. Technological innovations, such as high pressure injection systems, EGR loops and intake pressure boosting systems allow significant improvement of engine performance. Nevertheless, because of the high number of calibration parameters, combustion optimization becomes expensive in terms of resources. System simulation is a promising tool to perform virtual experiments and consequently to reduce costs, but for this models must be able to account for relevant in-cylinder physics to be sensitive to the impact of technology on combustion and pollutant formation.
2017-09-04
Technical Paper
2017-24-0018
Nikiforos Zacharof, Georgios Fontaras, Theodoros Grigoratos, Biagio Ciuffo, Dimitrios Savvidis, Oscar Delgado, J. Felipe Rodriguez
Heavy-duty vehicles (HDVs) account for some 5% of the EU’s total greenhouse gas emissions. They present a variety of possible configurations that are deployed depending on the intended use. This variety makes the quantification of their CO2 emissions and fuel consumption difficult. For this reason, the European Commission has adopted a simulation-based approach for the certification of CO2 emissions and fuel consumption of HDVs in Europe; the VECTO simulation software has been developed as the official tool for the purpose. The current study investigates the impact of various factors on the CO2 emissions of European trucks through vehicle simulations performed in VECTO. The chosen vehicles represent average 2015 vehicles and comprised of two rigid trucks (12 t and 18 t) and two tractor trailers (30 t and 40 t), which were simulated under their reference configurations and official driving cycles.
2017-09-04
Technical Paper
2017-24-0145
Marco Piumetti, Debora Fino, Nunzio Russo, Samir Bensaid, Melodj Dosa
A set of CeO2 nanocatalysts with different structural properties (nanocubes, nanorods, high-surface area CeO2) was prepared to investigate the shape-dependency activity for two oxidation reactions: the soot combustion under different soot-catalyst contact conditions (namely, in “loose” and “tight” conditions) and the CO oxidation. The physico-chemical properties of the prepared materials were investigated by complementary techniques (XRD, N2-physisorption at -196 °C, H2-TPR, FESEM, TEM, micro-Raman, FT-IR, XPS). As a whole, the best performances in terms of soot combustion have been achieved for the CeO2-nanocubes (SBET = 4 m2g-1), due to the abundance of highly reactive (100) and (110) exposed surfaces. On the other hand, better results in terms of the onset of soot oxidation (T10%) have been obtained for high-surface-area materials (SBET = 75 m2g-1), thus reflecting the key role of the surface area at low reaction temperature.
2017-09-04
Technical Paper
2017-24-0143
Sathaporn Chuepeng, Kampanart Theinnoi, Manida Tongroon
The combustion in reactivity controlled compression ignition (RCCI) mode of diesel engine have been gained more attention as one among other strategies to increase operating range for premixed combustion and to improve fuel economy. A low reactivity fuel such as high octane number fuel, alcohol blends for example, is early fumigated (or injected) and premixed with air prior to induction to the combustion chamber. Later on adjacent to the end of the compression stroke, the diesel fuel as a high reactivity fuel is directly injected into the homogeneous pre-mixture and ignited. This can also promote lower nitrogen oxides and particulate matter emissions. The main aim of this work is to characterize the combustion phenomena and particulate matter in nano-size from the RCCI engine using neat hydrous ethanol as the low reactivity fuel.
2017-09-04
Technical Paper
2017-24-0141
Riccardo Amirante, Elia Distaso, Silvana Di Iorio, Davide Pettinicchio, Paolo Sementa, Paolo Tamburrano, Bianca Maria Vaglieco
It is common knowledge that of all the regulated automotive emissions, particulate emissions are most difficult to quantify as they comprise a complex mixture of particles of varying size and composition, each of which may be influenced by many external factors including engine technology, fuel composition, air-to-fuel ratio, lubricant oil, after-treatment and the act of measurement itself. The aim of the present work is to provide further guidance into better understanding the production mechanisms of such emissions in spark-ignition engines fueled with compressed natural gas. In particular, extensive experimental investigations were designed with the aim to isolate the contribution of the fuel from that of lubricant oil to particle emissions.
2017-09-04
Technical Paper
2017-24-0139
Francesco Barba, Alberto Vassallo, Vincenzo Greco
The aim of the present study is to improve the effectiveness of the engine and aftertreatment calibration process through the critical evaluation of several methodologies available to estimate the soot mass flow produced by diesel engines and filtered by Diesel Particulate Filters (DPF). In particular, the focus of the present study has been the development of a reliable simulation method for the accurate prediction of the engine-out soot mass flow starting from Filter Smoke Number (FSN) measurements executed in steady state conditions, in order to predict the DPF loading considering different engine working conditions corresponding to NEDC and WLTP cycles. In order to achieve this goal, the study was split into two parts: - Correlation between ‘wet soot’ (measured by soot filter weighing) and the ‘dry soot’ (measured by the Micro Soot Sensor MSS).
2017-09-04
Technical Paper
2017-24-0132
Martin Großbichler, Zhen Zhang, Philipp Polterauer, Harald Waschl
To meet current legislation limits, modern diesel engines already achieve very low raw emission levels and utilize additional components for aftertreatment. However, during fast transients still undesired emission peaks can occur for both soot and NOx. These are caused by differences in the in-cylinder conditions between the quasi steady state engine calibration and the transient engine operation, e.g. during tip-ins. These effects become more and more important in view of future RDE emission test cycles. In this work a case study is performed to analyze the potential reduction of transient soot emissions during a specified engine maneuver. An additional target is to investigate potential benefits of a novel in-situ soot sensor based on the Laser Induced Incandescence (LII) principle which offers a high temporal resolution.
2017-09-04
Technical Paper
2017-24-0133
Jelica Pavlovic, Alessandro Tansini, Georgios Fontaras, Biagio Ciuffo, Marcos Garcia Otura, Germana Trentadue, Ricardo Suarez Bertoa, Federico Millo
Plug-in Hybrid Electric Vehicles (PHEVs) are one of the main options for reducing vehicle CO2 emissions and helping vehicle manufacturers (OEMs) to meet the CO2 targets imposed by different Governments from all around the world. In Europe OEMs have introduced a significant number of PHEV models to meet their CO2 target of 95 g/km for passenger cars set for 2021. Fuel consumption and CO2 emissions from PHEVs, however, strongly depend on the way they are used and on the frequency with which their battery is charged by the user. Studies have indeed revealed that in real life, with poor charging behavior from users, PHEV fuel consumption is equivalent to that of conventional vehicles, and in some cases higher, due to the increased mass and the need to keep the battery at a certain charging level.
2017-09-04
Technical Paper
2017-24-0130
Antonio Paolo Carlucci, Marco Benegiamo, Sergio Camporeale, Daniela Ingrosso
Nowadays, In-Cylinder Pressure Sensors (ICPS) have become a mainstream technology that promises to change the way the engine control is performed. Among all the possible applications, the prediction of raw (engine-out) NOx emissions would allow to eliminate the NOx sensor currently used to manage the after-treatment systems. In the current study, a semi-physical model already existing in literature for the prediction of engine-out nitric ox-ide emissions based on in-cylinder pressure measurement has been improved; in particular, the main focus has been to improve nitric oxide prediction accuracy when injection timing is varied. The main modification introduced in the model lies in taking into account the turbu-lence induced by fuel spray and enhanced by in-cylinder bulk motion.
2017-09-04
Technical Paper
2017-24-0131
Sergio Mario Camporeale, Patrizia D. Ciliberti, Antonio Carlucci, Daniela Ingrosso
The incoming PostEuro6 regulation and the on-board diagnostics -OBD- pushes the research activity towards the set-up of even more efficient after treatment systems. Nowadays, the most common after treatment system for NOx reduction is the selective catalytic reactor –SCR- . This system requires as an input the value of engine out NOx emission –raw- in order to control the Urea dosing strategy. In this work, a grey box NOx raw emission model based on in-cylinder pressure signal (ICPS) is validated on two standard cycles: MNEDC and WLTC using an EU6 engine at the test bench. The overall results show a maximum relative error of the integrated cumulate value integral of 12.8% and 17.4% for MNEDC and WLTC respectively. In particular, the instantaneous value of relative error is included in the range of ± 10% in the steady state conditions while during transient conditions is less than 20% mainly.
2017-09-04
Technical Paper
2017-24-0127
Lauretta Rubino, Dominic Thier, Torsten Schumann, Stefan Guettler, Gerald Russ
With the increasing number of engines utilizing direct fuel injection and the upcoming more stringent emission legislation, regulating not only particulate mass (PM) but particulate number (PN), emissions of Direct Injection Spark Ignition Engines (DISI) are becoming of increasing concern. Gasoline Particle Filters (GPF) represent a novel potential measure to reduce particle number emissions from DISI engines and are particularly effective in view of the tight particle number limits requirements at cold start and over RDE. Even if some learning from the development and application of particulate filters to diesel engines can be transferred to gasoline engines, the particulate consistence, the mass to number ratio and the temperature as well as the gas composition of gasoline engines are significant different to diesel engines. Therefore, there is the need to study the application of particulate filters to gasoline engines carefully.
2017-09-04
Technical Paper
2017-24-0126
Christian Zöllner, Dieter Brueggemann
The removal of particulate matter (PM) from diesel exhaust is necessary to protect the environment and human health. To meet the strict emission standards for diesel engines an additional exhaust aftertreatment system is essential. Diesel particulate filters (DPF) are established devices to remove emitted PM from diesel exhaust. But the deposition and the accumulation of soot in the DPF influences the filter back pressure and therefore the engine performance and the fuel consumption which is why a periodical regeneration through PM oxidation is necessary. The oxidation behavior should result in an effective regeneration mode that minimizes the fuel penalty and limits the temperature rise while maintaining a high regeneration efficiency. Excessive and fast regenerations have to be avoided as well as uncontrolled oxidations leading to damages of the filter and fuel penalty.
2017-09-04
Technical Paper
2017-24-0111
Heechang Oh, JuHun Lee, Seungkook Han, Chansoo Park, Choongsik Bae, Jungho Lee, In Keun Seo, Sung Jae Kim
In this study, the effect of nozzle tip geometry on nozzle tip wetting and particulate emissions was investigated. Various design concepts of injector nozzle hole were newly developed for this study. Spray and emission characteristics of each concept were discussed with experimental results. The macroscopic spray visualization was carried out in a constant volume chamber to investigate general spray characteristics of each nozzle hole concept. The laser induced fluorescence technique was applied to evaluate fuel wetting characteristics on the nozzle tip. The vehicle test and emissions measurement in chassi dynamo were performed to investigate particulate emission characteristics for various injector nozzle designs. In addition, during a vehicle test, the in-cylinder combustion visualization with the optical fiber sensor (AVL VISIO VOLUME) was conducted to provide a comprehensive understanding of diffusion combustion and wetting behavior.
2017-09-04
Technical Paper
2017-24-0121
Ivan Arsie, Giuseppe Cialeo, Federica D'Aniello, Cesare Pianese, Matteo De Cesare, Luigi Paiano
The demand for high NOx conversion efficiency and low tailpipe ammonia slip for urea-based selective catalytic reduction (SCR) systems has substantially increased in the past decade, as NOx emission legislations for Diesel engines are becoming more stringent than ever before. Model-based control strategies are fundamental to meet the dual objective of maximizing NOx reduction and minimizing NH3 slip in urea-SCR catalysts. In this paper, a control oriented model of a Cu-zeolite urea-selective catalytic reduction (SCR) system for automotive diesel engines is presented. The model is derived from a quasi-dimensional four-state model of the urea-SCR plant. In order to make it suitable for the real-time urea-SCR management, a reduced order one-state model has been developed, with the aim of capturing the essential behavior of the system with a low computational demand. The model estimates the relevant species (i.e. NO, NO2 and NH3) independently.
2017-09-04
Technical Paper
2017-24-0092
Francesco Catapano, Silvana Di Iorio, Paolo Sementa, Bianca Maria Vaglieco
Fuel depletion as well as the growing concerns on environmental issues prompt to the use of more environmental friendly fuels. The natural gas (CNG) is considered one of the most promising alternative fuel for engine applications because of the lower emissions. Nevertheless, recent studies highlighted the presence of ultrafine particle emissions at the exhaust of CNG engines. The present study aims to investigate the effect of CNG on particle formation and emissions when it was direct injected and when it was dual fueled with gasoline. The study was carried out on a transparent small displacement single cylinder SI engine. The engine was fueled with CNG and gasoline, both simultaneously and not. In particular, CNG and gasoline were direct injected in the combustion chamber. For dual fuel configuration, instead, the CNG was direct injected and the gasoline port fuel injected. In-cylinder 2D images of flame evolution were detected. The flame front propagation was calculated.
2017-09-04
Technical Paper
2017-24-0096
Laura Sophie Baumgartner, Stephan Karmann, Fabian Backes, Andreas Stadler, Georg Wachtmeister
Due to its molecular structure, methane provides several advantages as fuel for internal combustion engines. First, owing to the single carbon atom per molecule, a formation of particular matter becomes drastically more unlikely and second the carbon to hydrogen ratio of methane reduces the amount of carbon dioxide by 20 % at the same energy output. To cope with nitrogen oxide emissions a high level of excess air is beneficial, which on the other hand deteriorates the flammability and combustion duration of the mixture. One approach to meet these challenges and ensure a stable combustion process are fuel scavenged prechambers. The flow and combustion processes within these prechambers are highly influenced by the position, orientation, number and overall cross-sectional area of the orifices connecting the prechamber and the main combustion chamber.
2017-09-04
Technical Paper
2017-24-0076
Mark A. Hoffman, Ryan O'Donnell, Zoran Filipi
The proven impact of combustion chamber deposits on advanced compression ignition combustion strategies has steered recent works toward the development of thermal barrier coatings, which can mimic their benefits on combustion efficiency and operational range expansion. However, recent work based on statistical thermodynamics has indicated that inter-molecular radiation during the combustion event may subject the combustion chamber walls to non-negligible radiation heat transfer, regardless of the relatively low soot formation within the well-mixed and lean charge. In the present paper, the impact of radiation heat transfer on combustion chamber deposits and thermal barrier coatings is studied. The morphological construction of the combustion chamber deposit layer is shown to be partially transparent to radiation heat transfer, drawing corollaries with ceramic based thermal barrier coatings.
2017-09-04
Technical Paper
2017-24-0085
Jesus Benajes, Antonio Garcia, Javier Monsalve-Serrano, Vicente Boronat
This work investigates the particulates size distribution of reactivity controlled compression ignition combustion, a dual-fuel concept which combines port fuel injection of low reactive/gasoline-like fuels with direct injection of diesel fuel, when implemented in a medium-duty diesel engine. The particulates size distribution measurement was also carried out for conventional diesel combustion at six engine speeds, from 950 to 2200 rpm, and 25% engine load. For this purpose, a scanning mobility particle sizer was used to measure the particles size distribution from 5-250 nm. Both combustion strategies were conducted in a single-cylinder engine derived from a stock medium-duty multi-cylinder production engine with a compression ratio of 15.3. The combustion strategy proposed during the tests campaign was limited to accomplish mechanical as well as emissions constraints.
2017-09-04
Technical Paper
2017-24-0067
Yoshiaki Toyama, Nozomi Takahata, Katsufumi Kondo, Tetsuya Aizawa
In order to better understand in-flame diesel soot oxidation processes, soot particles at the oxidation-dominant periphery of diesel spray flame were sampled by a newly developed “suck” type soot sampler employing a high-speed solenoid valve and their morphology and nanostructure were observed via High-Resolution Transmission Electron Microscopy (HR-TEM). A single-shot diesel spray flame for the soot sampling experiment was achieved in a constant-volume vessel under a diesel-like condition. The sampler quickly sucks out a small portion of soot laden gases from the flame. A TEM grid hold inside the flow passage close to its entrance is immediately exposed to the gas flow induced by the suction at the upstream of the solenoid valve, so that the quick thermophoretic soot deposition onto the grid surface can effectively freeze morphology variation of soot particles during the sampling processes.
2017-09-04
Technical Paper
2017-24-0086
Yanzhao An, S. Vedharaj, R. Vallinayagam, Alaaeldin Dawood, Jean-Baptiste MASURIER, Mohammad Izadi Najafabadi, Bart Somers, Junseok Chang, Bengt Johansson
Compared to conventional Compression Ignition (CI), both of Homogeneous Charge Compression Ignition (HCCI) and Partially Premixed Combustion (PPC) concepts have shown high efficiency with low soot emissions. However, soot measurements are rarely investigated and correlated with in-cylinder combustion in an optical diesel engine. The objective of this study is to investigate the effect of addition of toluene (aromatic) to primary reference fuel, PRF60, on combustion stratification and particulate emissions. Experiments are performed in an optical CI engine at a speed of 1200 rpm for TPRF0 (60% iso-octane + 40% n-heptane), TPRF20 (33.5% iso-octane + 46.5% n-heptane + 20% toluene) and TPRF40 (6% iso-octane + 54% n-heptane + 40% toluene). TPRF mixtures are prepared in such a way that the RON of all test blends are same (RON = 60) to account for the influence of aromatics in TPRF mixtures. The motored pressure at TDC is maintained at 35 bar and fuelMEP is kept constant at 5.1 bar.
2017-09-04
Technical Paper
2017-24-0077
Matteo Pelucchi, Mattia Bissoli, Cristina Rizzo, Yingjia Zhang, Kieran Somers, Alessio Frassoldati, Henry Curran, Tiziano Faravelli
Pursuing a sustainable energy scenario for transportation requires the blending of renewable oxygenated fuels such as alcohols into commercial hydrocarbon fuels. From a chemical kinetic perspective, this requires the accurate description of both hydrocarbon reference fuels (n-heptane, iso-octane, toluene, etc.) and oxygenated fuels chemistry. A recent systematic investigation of linear C2–C5 alcohols ignition in a rapid compression machine at p = 10–30 bar and T = 650–900 K has extended the scarcity of fundamental data at such conditions allowing for a revision low temperature chemistry for alcohol fuels in the POLIMI mechanism. Heavier alcohols such as n-butanol and n-pentanol present ignition characteristic of interest for application in HCCI engines, due to the presence of the hydroxyl moiety reducing their low temperature reactivity compared to the parent linear alkanes (i.e. higher octane number).
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