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2015-04-23 ...
  • April 23-24, 2015 (8:30 a.m. - 4:30 p.m.) - Detroit, Michigan
  • October 22-23, 2015 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
Attendees to the seminars held in conjunction with the SAE 2015 World Congress will receive COMPLETE access to Congress activities for only $55 per day. If interested, please contact our Customer Service department at +1.877.606.7323 (U.S. and Canada only) or +1.724.776.4970 (outside U.S. and Canada) to register for this special Congress daily rate. Engines can and do experience failures in the field in a variety of equipment, vehicles, and applications.
2015-04-21
Event
This session focuses on basic SI combustion processes including studies of mixture formation, engine efficiency, flame propagation, and emissions formation. 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.
2015-04-21
Event
Focuses on SI combustion technologies that employ direct, in-cylinder fuel injection. Topics of particular interest include in-cylinder fuel injection and spray studies, flow/spray interaction and in-cylinder mixture formation studies, and combustion chamber shape optimization. Focus includes "stratified" operation or other modes enabled by DI hardware, DI-specific emissions issues such as particulates and smoke, and technologies enabled by DISI (such as downsizing).
2015-04-21
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.
2015-04-21
Event
This session focuses on the impact of conventional and alternative fuels as well as fuel additives on the operation, performance and emissions of SI engines. Papers focus on the impact of bio-derived fuels (ethanol, butanol and others) on engine design and performance as well as gasoline properties and additives, and their impact.
2015-04-21
Event
This session focuses on the SI combustion ignition process and advanced ignition systems. 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.
2015-04-21
Event
This session focuses on the dilute SI combustion processes including lean, stratified, and EGR operation. 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.
2015-04-14
Technical Paper
2015-01-1718
Jan Macek, Zdenek Zak, Oldrich Vitek
Aiming at high low-end ICE torque with turbocharged and massively downsized engines revitalized high pulsation exhaust manifolds, which improve exhaust gas energy transfer especially while engine runs at reduced speed. The lack of turbine maps if twin scroll or divided scroll is used for radial turbine stator entry is well-known. The remedy is not simple. The measurements of maps for twin-entry turbines are costly and time consuming. Any lookup-map based interpolation suffers from lack of physical fundamentals, since the mixing processes take place inside a turbine at governing pressure differences significantly different from turbine inlet pressures. The paper describes a way to a 1-D central streamline model of a radial turbine flow suitable for twin-scroll description based on approximation to real physics of flow mixing and energy transformation.
2015-04-14
Technical Paper
2015-01-1719
Daniel Pachner, Lukas Lansky, David Germann, Markus Eigenmann
Turbocharger maps measured on the gas stand are commonly used to represent turbine and compressor performance. The maps are useful source of information for mean value modeling, engine calibration optimization, virtual sensing and feedback control design. For some tasks, representing the maps by fitted functional forms can be more convenient than using the interpolation of the map data directly. The functional representation usually allows for wider extrapolation ranges and more reliable application of numerical optimization methods. Several functional forms have been proposed for compressor map modeling, often based on empirical polynomial models. However, most successful models are based rational polynomials of dimensionless head and flow parameters (Winkler, Jensen). The turbines are usually modeled as orifices, or orifices with variable cross-section in case of variable nozzle (VNT) turbines.
2015-04-14
Technical Paper
2015-01-1716
Oldrich Vitek, Jan Macek, Jiri Klima, Martin Vacek
The proposed paper deals with an optimization of a highly-turbocharged large-bore gas SI engine. Only steady state operation (constant engine speed and load) is considered. The results are obtained by means of simulation using complex 0-D/1-D engine model including the control algorithm. Different mixture composition concepts are considered to satisfy TA Luft norm (different levels of TA Luft NOx limit are evaluated) – fresh air and external cooled EGR is supposed to be the right way while optimal EGR level is to be found. Considering EGR circuit, 5 different layouts are tested to select the best desing. As the engine control is relatively complex (2-sage turbocharger group, external EGR, compressor blow-by, controlled air excess), 5 different control means of boost pressure were considered. Each variant (based on above mentioned possibilities) is optimized in terms of compressor/turbine size (swallowing capacity) to obtain the best possible BSFC.
2015-04-14
Technical Paper
2015-01-1717
Li-Chun Chien, Matthew Younkins, Mark Wilcutts
Dynamic skip fire is a control method for internal combustion engines in which engine cylinders are selectively fired or skipped to meet driver torque demand. Each cylinder is operated at or near its best thermal efficiency and flexible control of acoustic and vibrational excitations is achieved. In this type of engine operation, fueling, and possibly intake and exhaust valves of each cylinder are actuated on an individual firing opportunity basis. The implementation and benefits of this system have been described in several previous papers. This paper describes engine thermofluid modeling for this type of operation for purposes of air flow and torque prediction. Airflow dynamic and thermodynamic results for skip fire engine operation are presented and compared with experimental data under several different firing sequences. Unique impacts of dynamic skip fire on air estimation, and performance parameters are discussed.
2015-04-14
Technical Paper
2015-01-1750
Stijn Broekaert, Thomas De Cuyper, Kam Chana, Michel De Paepe, Sebastian Verhelst
Homogeneous charge compression ignition (HCCI) engines are a promising alternative to traditional spark- and compression-ignition engines. The HCCI combustion principle makes it possible to achieve both a high thermal efficiency and near-zero emissions of NOx and soot. This is obtained by introducing a lean premixed fuel-air mixture into the combustion chamber and letting it auto-ignite due to the temperature rise during the compression stroke. The main drawbacks of HCCI combustion are the lack of direct control over the start of combustion and a limited operating range. Trying to overcome these drawbacks and further optimizing the engine, solely using an experimental approach is very time consuming. Therefore simulation tools are being developed. An important model required by these simulation tools, is a model that calculates the heat transfer from the bulk gas to the walls of the combustion chamber.
2015-04-14
Technical Paper
2015-01-1752
Alex Melin, David Kittelson, William Northrop
In recent years, there has been growing interest in using alternative cycles to the standard Otto cycle in an effort to improve efficiency and lower emissions of spark-ignition engines. One such proposed concept is the 5-stroke engine. The 5-stroke uses two types of cylinders, a combustion cylinder and expansion cylinder with a transfer port between them. Excess pressure in the combustion cylinder can be further expanded by using a second expansion cylinder to harness additional work; a practical implementation of the Atkinson Cycle. Since the expansion cylinder runs on a two-stroke cycle, an additional increase in efficiency can result by connecting two combustion cylinders to one expansion cylinder in a three cylinder configuration. Although previous work has investigated the performance of prototype 5-stroke engines compared to1-D modeling results, none have conducted a thorough study on the interactions of various design parameters.
2015-04-14
Technical Paper
2015-01-1753
Mario Vila Millan, Stephen Samuel
Nanofluids and thermal management strategy for Automotive Application Mario Vila Millan, Stephen Samuel Oxford Brookes University, United Kingdom Stringent emission norms introduced by the legislators over the decades have forced the automotive manufacturers to improve the fuel economy and emission levels of their engine continuously. This constant improvement leads to increased use of smart systems where components are controlled by the engine management systems to get a desired and optimized performance. Therefore, the emission levels of the modern engines are significantly lower than pre-1990 engines. However, the improvement in fuel economy is marginal when compared to that of the scale of improvement achieved for reducing emission levels. For example, approximately 30% of the total energy in the fuel is still being wasted through the cooling systems in the modern engines during normal operating conditions. This is even worse during the engine warm up.
2015-04-14
Technical Paper
2015-01-1749
Hung Nguyen Ba, Ocktaeck Lim, Norimasa Iida
In a linear engine, the piston motion is not restricted by a crankshaft mechanism, but it is determined by the interaction between the gas and load forces. Therefore, the compression ratio of the linear engine is variable and it allows the engine to operate with the HCCI combustion. However, it is difficult to obtain a high compression ratio as well as a HCCI combustion from motoring mode of the linear engine due to lack of a crankshaft. In this paper, an idea using SI-HCCI transition to achieve the HCCI combustion is proposed. The spark ignition (SI) mode is used first to increase compression ratio before the homogeneous charge compression ignition (HCCI) mode is activated by turning off spark plugs. The operation of the linear engine is modeled and simulated by dynamic and thermodynamic models.
2015-04-14
Technical Paper
2015-01-0746
Walter F. Piock, Bizhan Befrui, Axel Berndorfer, Guy Hoffmann
Abstract: The GDi homogeneous combustion system is broadly adopted by the global automotive industry as the primary technology – in conjunction with downsizing and turbo-charging – for improvement of the gasoline engine fuel economy and performance. The challenge for the GDi homogenous combustion technology is the continuous market and regulatory pressures for improvement of fuel economy and reduction of the combustion emissions. In Europe, the primary challenge is viewed to be the Euro6C stringent limit on the particulate emissions. This has brought the focus of attention on the strategies for improvement of in-cylinder mixture preparation and identification / elimination of the sources of combustion emissions, in particular the in-cylinder particulate formation. This paper presents an investigation of the effects of fuel system pressure increase, injector seat specification and enhancement of the tumble charge motion on the GDi engine particulate emissions and fuel economy.
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
Technical Paper
2015-01-0762
Mitsuru Kowada, Isao Azumagakito, Tetsuya Nagai, Nobuyuki Iwai, Ryoji Hiraoka
Growing demand for a fuel economy calls for enhancement in thermal efficiencies of internal combustion engines. One of the measures for increasing this thermal efficiency is applying a higher compression ratio. However, when it is applied to a gasoline engine, it is inevitably subject to restrictions of the knocking limits. Knocking is the phenomenon in which the unburned air-fuel mixture gas causes auto-ignition generating a shockwave within the combustion cylinder accompanied by its characteristic noise. The knocking with a large intensity seriously deteriorates the engine. To enhance thermal efficiency of an engine while maintaining its durability, a quantitative evaluation of knocking intensities is necessary in the process of an engine development. Numerous studies have been conducted so far on knocking analyses and their intensity measurements.
2015-04-14
Technical Paper
2015-01-0765
Chenglong Tang, Zhanbo Si, Shuang Zhang, Zuohua Huang, Shiyi Pan, Jinhua Wang, Jing Gong
The specific heat ratio used in heat release calculation plays an important role and the mass fraction burned is also a crucial parameter in thermodynamics analysis for engine combustion. A research of high methane fraction natural gas was investigated in a constant volume combustion vessel at different initial conditions. Results show that with the increase of the initial pressure, the specific heat ratio is decreased, and the time of the mixture burned up is postponed, while the peak heat release ratio is increased. With the increase of the methane fraction, the parameters have the opposite behavior. With the increase of the initial temperature, the specific heat ratio is decreased, and the time of the mixture burned up is accelerated, and the peak heat release ratio has no obviously difference. With the increase of the dilute ratio or the CO2/N2 ratio, the specific heat ratio is decreased, and the peak heat release heat ratio is decreased.
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
2015-01-1715
Farouq Meddahi, Alain Charlet, Yann Chamaillard, Christian Fleck
Compressor models play a major role as they define the boost pressure in the intake manifold. These models have to be suitable for real-time applications such as control and diagnosis and for that; they need to be both accurate and computationally inexpensive. However, the models available in the literature usually fulfil only one of these two competing requirements. On the one hand, physics-based models are often too complex to be evaluated on line. On the other hand, data-based models generally suffer insufficient inter- and extrapolation features. To combine the merits of these two types of models, this work presents an extended approach to compressor modelling with respect to thermo- and aerodynamic losses. In particular, the model developed by Martin et al. [1] is augmented to explicitly incorporate friction, incidence and transfer losses.
2015-04-14
Technical Paper
2015-01-1265
Yoann Viollet, Marwan Abdullah, Abdullah alhajhouje, Junseok Chang
In a regulatory environment for spark ignition (SI) engines where the focus is continuously looking into improvements in fuel economy and reduction in noxious emissions, the challenges to achieve future requirements are utmost. In order to effectively reduce CO2 emissions on a well to wheel basis, future fuels enabling high efficiency SI engines will have to not only satisfy advanced engine requirement, i.e. high knock resistance, but also produces less CO2 emissions in the refinery. In this paper, compression ratio 10.5 single cylinder SI engine test were conducted to characterize combustion with two dual fuel configurations. Straight run refinery naphtha was used for low octane component, and two oxygenates were used for high octane knock inhabitant component, such as, Methanol and MTBE (Methyl Tert-Butyl Ether). Research Octane Number (RON) of naphtha was 61, while RON of Methanol was 106 and RON of MTBE was 116.
2015-04-14
Technical Paper
2015-01-1645
Thomas De Cuyper, Gery Fossaert, Olivier Collet, Stijn Broekaert, Kam Chana, Michel De Paepe, Sebastian Verhelst
In the development and optimization of internal combustion engines, simulation tools gain in importance as they are a more cost effective solution in the optimization process than just relying on experimental optimization. An important sub-model in these simulation tools is the heat transfer model that predicts the heat loss from the combustion gases to the chamber walls. This heat transfer has a large effect on the efficiency, emissions and power output. Accurate measurements of the heat flux are essential to build an adequate heat transfer model. These measurements are required to fully understand the heat transfer phenomena in a combustion chamber. The Thin Film Gauge heat flux sensor has been proven to be an adequate sensor for this purpose. This paper reports on the calibration of the TFG sensor for measurements in internal combustion engines. A TFG sensor consists of a platinum thin film which serves as a resistance temperature detector on an insulating substrate (ceramic).
2015-04-14
Technical Paper
2015-01-0748
Simona Silvia Merola, Adrian Irimescu, Cinzia Tornatore, Luca Marchitto, Gerardo Valentino
In this study, experiments were conducted on a transparent single-cylinder Direct Injection Spark Ignition engine fueled with n-butanol and gasoline alternatively. The engine is equipped with the head of a commercial turbocharged engine with similar geometrical specifications (bore, stroke, compression ratio). The head has four valves and a centrally located spark device with surface charge ignition. A conventional elongated hollow Bowditch piston is used and an optical crown, accommodating fused-silica window, is screwed onto it. The injector is side mounted and features 6 holes oriented so that the spray is directed towards the piston crown. During the experimental activity, the injection pressure was maintained at 100 bar for all conditions; the injection timing and the number of injections were adjusted to investigate their influence on combustion and emissions.
2015-04-14
Technical Paper
2015-01-1714
Usman Asad, Jimi Tjong
Exhaust gas recirculation (EGR) is the most widely used and effective NOx control strategy in modern diesel engines. The authors have previously demonstrated that the intake dilution provides a reliable and quantitative measure of the EGR effectiveness in reducing NOx emissions (SAE 2014-01-1092). With highly boosted (turbocharged) diesel engines and the lean nature of diesel combustion, the real-time estimation of the intake dilution (intake oxygen) becomes a challenging task since the established relationship between the intake dilution and the EGR rate for naturally aspirated engines becomes invalid. The intake charge dilution at any EGR ratio is a function of engine load and intake pressure, and typically changes during transient events.
Viewing 1 to 30 of 9056

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