Download or read book THE INTERACTION OF IGNITION AND IN CYLINDER FLOW ON FLAME KERNEL DEVELOPMENT AND ITS IMPACTS ON COMBUSTION IN AN OPTICALLY ACCESSIBLE DIRECT INJECTION ENGINE written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : A significant challenge facing spark-ignited (SI) engines to achieve higher efficiency via highly diluted combustion is the quickly increased combustion instability as the dilution level increases. The flow motion variation has been identified as a dominant factor that introduces combustion variability at highly diluted conditions. However, the detailed mechanism of how the variation in flow motion impacts the flame kernel development and introduces combustion instability is only partially understood. This research investigated the impacts of the in-cylinder flow on variability of the ignition and early flame kernel development in a single cylinder direct-injection spark-ignition (DI-SI) optically accessible engine and accessory test benches. Firstly, different types of spark plug electrode designs were studied on a spark plug flow fixture bench. The results showed that the impacts of incoming flow on the ignition output vary as the incoming flow direction is changed. The ignition energy drops and discharge duration prolongs as the incoming flow is blocked by any part of the electrodes. Secondly, the flow motion near the spark plug region was investigated in an optical engine through high-speed imaging of the spark discharge arc stretching and flow field measurement via particle imaging velocimetry. It was observed that at motored conditions there is a consistent trend that the flow can change direction from the bulk motion as the piston approaches the top dead center (TDC). The transition of flow direction near the spark plug is a source of variability in initial flame kernel convection and propagation. It was found that by increasing the tumble motion, the transition window can be retarded later in the cycle. Lastly, the impacts of the unstable incylinder flow motion on the flame kernel initiation and development was studied at both diluted and stoichiometric conditions. The 2D and 1D probability distribution functions of the flame kernel indicated that the reversed flow direction near the spark plug at ignition timing results in smaller and less stretched flame kernels, which are a source of combustion variability. As the tumble level is increased, the window where the transition of flow direction occurs near the spark plug also changes. This research indicates that, at the studied loads and speeds, higher tumble level helps maintain a consistent flow motion near the spark plug at the ignition timing, which results in faster growing flame kernels.
Download or read book The Influence of In cylinder Flows on the Flame Kernel Growth in Natural Gas Fuelled Spark Ignition Engines written by Richard J. Ancimer and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this work was to determine the influence of in-cylinder flows on the natural gas combustion process in configurations representative of light duty vehicle spark ignition engines. Specifically, the influence of the flow field on the flame kernel development period was of interest. The interactions between the flow field and the combustion process were quantified by correlating characteristic in-cylinder fluid flow and mass burn rate parameters. The fluid motion, flame kernel development and the overall combustion duration were characterised using: (i) a two-component laser Doppler velocimeter for the in-cylinder fluid flow, (ii) a fibre-optic instrumented spark plug for the flame kernel growth rate, and (iii) a piezo-electric pressure transducer for the in-cylinder pressure from which the overall mass burn rate data is obtained. The measurements were made on an individual cycle basis. Results from a single cylinder V6 optical engine are reported. Physical interpretations of: (i) the flow field evolution and (ii) the interactions between the flow field and the natural gas combustion process are presented. The main contributions of this work are through: (i) the application of novel data processing techniques, and (ii) the exploration of the fibre-optic instrumented spark plug as a measurement technique in high swirl engines. For example, the discrete wavelet transform is used to show: (i) the energy cascade process in the non-stationary engine flow field over crank angle phase and frequency; and (ii) how the flow field evolution influences the early stages of the natural gas combustion process. The fibre-optic instrumented spark plug is shown to measure a mass-weighted velocity. Data from the fibre-optic instrumented spark plug data are shown to be biased by the large convection velocities in high swirl engines. This work provides the foundation upon which further investigations into the influence of different in-cylinder flows on the natural gas combustion process in spark ignition engines can be based.
Download or read book Proceedings of the 4th International Congress of Automotive and Transport Engineering AMMA 2018 written by Nicolae Burnete and published by Springer. This book was released on 2018-09-29 with total page 866 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume includes selected and reviewed papers from the 4th International Congress of Automotive and Transport Engineering, held in Cluj, Romania, in September 2018. Authors are experts from research, industry and universities coming from 14 countries worldwide. The papers are covering the latest developments in automotive vehicles and environment, advanced transport systems and road traffic, heavy and special vehicles, new materials, manufacturing technologies and logistics, accident research and analysis and innovative solutions for automotive vehicles. The conference is organized by SIAR (Society of Automotive Engineers from Romania) in cooperation with FISITA.
Download or read book Annual Index abstracts of SAE Technical Papers written by and published by . This book was released on 2007 with total page 1218 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Springer Handbook of Experimental Fluid Mechanics written by Cameron Tropea and published by Springer Science & Business Media. This book was released on 2007-10-09 with total page 1570 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accompanying DVD-ROM contains ... "all chapters of the Springer Handbook."--Page 3 of cover.
Download or read book Investigation of a Spark Ignition Flame Kernel Interacting with a Laminar Vortex Toroid written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemistry-turbulence interactions play a critical role in most practical combustion environments. Understanding the interaction between a flame kernel and a vortex is an important fundamental step. This dissertation presents high-speed movies of combustion luminosity during the interaction of a laminar vortex toroid with a spark -generated premixed flame kernel in a quiescent combustion chamber. The resulting time evolution of the perturbed flame kernel shows that laminar vortices of various sizes and vortex strengths can increase the kernel growth rate by at least a factor of 3 and significantly increase combustion reaction rates by involving additional highly curved and stretched flame fronts. This dissertation also describes experiments that were conducted to study the Lewis number effect on the flame kernel-vortex interaction. The influence of a time varying strain rate on kernel growth was investigated by studying both lean methane-air (thermo-diffusively unstable) and lean propane-air (thermo-diffusively stable) flame kernels, using both natural CH/OH emission image sequences acquired by a high-speed intensified camera to show details of the disturbed flame kernel growth, and OH-PLIF images to determine the true two-dimensional nature of the interaction. Significant differences are observed in the highly curved regions on the backside of the invading vortex in the two different mixtures. Lewis number effects on local burning rate variations, flame front wrinkling, and pocket formation are reported, and in general, the results are in agreement with predictions from asymptotic theory assuming low stretch rates. Local mixture enrichment by direct injection in the vicinity of the spark plug at the time of ignition can affect flame kernel development and extend the lean limit of flammability of a fuel/air mixture. In the third set of the experiments, flame kernels were ignited in a lean premixed CH4/air mixture with an equivalence ratio of 0.6, while CH4/air mixtur.
Download or read book FLUID MOTION EFFECT ON CYCLE TO CYCLE COMBUSTION VARIATION FLAME DEVELOPMENT AND SPARK DELIVERY IN SPARK IGNITION ENGINES written by PHILIP SHAFER KELLER and published by . This book was released on 1991 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: in the determination of the cycle-resolved mean velocity, the greater the correlation.
Download or read book The Influence of In cylinder Flows on the Flame Kernel Growth in Natural Gas Fuelled Spark Ignition Engines written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Intake Flow on Mixing and Combustion in Direct Injection Diesel Engines Using Multidimensional Modeling written by Philip William Stephenson and published by . This book was released on 1995 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Fuel Injection and Intake Airflow on Direct injection Spark ignition Combustion written by Won-Seok Chang and published by . This book was released on 2003 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technical Literature Abstracts written by Society of Automotive Engineers and published by . This book was released on 1999 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation of Preflame Reactions and Flame Propagation in Direct Injection Diesel Enginees written by and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: It was to investigate (invisible) preflame reactions taking place in a direct-injection compression ignition (DI-CI) engine during the ignition delay period and their effects on subsequent (visible) combustion reactions. The investigation was focused on the subject for an engine equipped with a high-pressure injection (HPI) unit in order to support the development of high-power-output Diesel engines. The use of HPZ was found to facilitate more air utilization in a DI-CI engine even operated with intake air at unusually high temperatures (e.g., encountered in uncooled engines). In order to achieve these goals, several new research methods were developed-advanced for the study, including Rutgers or Super Imaging System (SIS), spectrometric methods, and Rutgers Animation Program. The tools were employed on an optical single-cylinder Cummins 903 engine. Among the significant results in system development is that the basic methods for high-speed imaging achievable at consecutive cycles, which shed some new insight into complex in-cylinder phenomena. The new research methods developed under the present ARO study permits observation of timed global pictures of preflame propagation under various engine-fuel conditions. New findings of the study include that the fuel injected into the cylinder immediately commences to chemically react, unlike the previous thought that there is a physical delay proceeding actual chemical reactions. The reactions involved during the preflame reactions appear to be low-temperature kinetics controlled processes to affect the onset of visible-ray flame formation and combustion reactions. The preflame reaction species were found rapidly consumed as soon as the heat-releasing flame propagation took place.
Download or read book THE EFFECT OF DIRECTED MIXTURE MOTION ON THE FLAME KERNEL DEVELOPMENT IN A CONSTANT VOLUME BOMB written by David E. Cole and published by . This book was released on 1966 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Influence of In cylinder Flows on the Flame Kernel Growth in Natural Gas Fuelled Spark Ignition Engines microform written by Richard J. Ancimer and published by National Library of Canada = Bibliothèque nationale du Canada. This book was released on 2000 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Diesel Combustion and Emissions written by Society of Automotive Engineers and published by . This book was released on 1981 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamentals of Combustion Processes written by Sara McAllister and published by Springer Science & Business Media. This book was released on 2011-05-10 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals of Combustion Processes is designed as a textbook for an upper-division undergraduate and graduate level combustion course in mechanical engineering. The authors focus on the fundamental theory of combustion and provide a simplified discussion of basic combustion parameters and processes such as thermodynamics, chemical kinetics, ignition, diffusion and pre-mixed flames. The text includes exploration of applications, example exercises, suggested homework problems and videos of laboratory demonstrations
Download or read book Ignition Systems for Gasoline Engines written by Michael Günther and published by Springer. This book was released on 2016-11-18 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: The volume includes selected and reviewed papers from the 3rd Conference on Ignition Systems for Gasoline Engines in Berlin in November 2016. Experts from industry and universities discuss in their papers the challenges to ignition systems in providing reliable, precise ignition in the light of a wide spread in mixture quality, high exhaust gas recirculation rates and high cylinder pressures. Classic spark plug ignition as well as alternative ignition systems are assessed, the ignition system being one of the key technologies to further optimizing the gasoline engine.
