Download or read book Investigation of Transient Plasma Ignition for a Pulse Detonation Engine written by and published by . This book was released on 2005 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elimination or reduction of auxiliary oxygen use in Pulse Detonation Engines (PDEs) is necessary if the technology is to compete with existing Ramjet systems. This thesis investigated a Transient Plasma Ignition (TPI) system and found that the technology can at least reduce and may be able to completely remove the auxiliary oxygen requirement of current PDE systems. TPI was tested and compared with a traditional capacitive discharge spark plug system in a dynamic flow, ethylene/air mixture combustor. Ignition delay time, Deflagration-to-Detonation transition (DDT) distance and time, detonation wave speed and fire success rate performance were analyzed for various mass flow rates and stoichiometric ratios. A transient plasma dualelectrode concept was also employed and analyzed. Results show that TPI is more effective and reliable than the spark plug ignition with considerable improvements to DDT performance. The TPI dual-electrode concept was proven to be the most effective configuration with average reductions in DDT distance and time of 17% and 41% respectively when compared to the capacitive discharge spark plug system configuration.
Download or read book Energy Efficient Transient Plasma Ignition Physics and Technology written by and published by . This book was released on 2007 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: The project has conducted basic studies of flame ignition collaborative studies of pulse detonation ignition, and preliminary studies of fundamental issues relevant to the application of transient plasma as an ignition source for Air Force high-speed aircraft applications. Preliminary basic science experiments have been conducted at the Air Force Research Laboratory (AFRL) using planar laser-induced fluorescence (PLIF) for investigation of radical production and ignition delay. Very strong enhancement of radical species throughout the combusting volume using transient plasma for ignition (TPI) was demonstrated using PLIF, and the production of electronically excited species was well coordinated with TPI. In another study at AFRL systems were interfaced successfully with a pulse detonation engine (PDE), and data were taken for a variety of electrode lengths while burning aviation gasoline and ethylene. The project work also included development of appropriate ignition systems for these studies, comprised of pulse sources, transmission lines (cabling appropriate for nanosecond power pulses), and electrodes, and extending the work from laboratory pulse generation capabilities to considerable reduction in size and weight of the ignition pulse generation. This reduction is a critical issue in the application of this technology. The electrical engineering issues inherent in the application of the short pulses to fuel-air mixtures at various pressures and in a variety of geometries were addressed successfully in the project.
Download or read book Pulsed Power and Transient Plasmas Basic Research With Application to Ignition Emissions and New Pulsed Power Technology written by and published by . This book was released on 2004 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scientific progress lies in three areas: Pulsed power, transient plasma ignition, and applications of pulsed power to biology. We report here 1) Progress in studies of SiC pulsed power JFET devices for applications to pulsed power, 2) Significant progress in the application of transient plasma to ignition, with results during the previous year in the ignition of pulse detonation engines, and 3) Significant progress in the study of the effects of nanosecond pulsed electric fields on biological cells, including visualization of intracellular calcium bursts and certain additional processes in Jurkat-T lymphocytes. During the next year we plan to develop advanced pulse generation devices for both biological applications and transient plasma ignition, and conduct further experiments in collaborations with several institutions.
Download or read book Plasma Ignition Systems for Use in Pulsed Detonation Engines written by Jennifer Reilly Corrigan and published by . This book was released on 2006 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The Pulse Detonation Engine (PDE) is an extremely exciting type of pulsejet. With recent advances in technology, coupled with operational prospects, there has been a renewed interest in PDEs. Despite the advantages of the PDE, there are many improvements still to be made. One way of improving a PDE is to decrease ignition and deflagration to detonation transition (DDT) times. It is hypothesized that this can be accomplished with the use of plasma ignition systems because of the high energy capabilities of the system. While the high voltage requirements of a plasma ignition system would add complications to practical use of PDEs in aircraft, if the plasma ignition system can decrease the ignition delay and DDT times by a large amount, it would be most beneficial to use it. Lowering the ignition delay and DDT times would allow the PDE to operate at higher frequencies, decreasing lower frequency vibrations and increasing the thrust generated and overall efficiency. In this study, three plasma ignition systems were tested in various positions throughout the PDE cylinder head. The results of the experimental testing showed that the plasma ignition systems were able to reduce the ignition delay by a factor of two, but the DDT times for the plasma ignition systems showed a large variance. There were also complications with the plasma ignition systems due to the harsh environment of the PDE.
Download or read book Detonation Initiation in a Pulse Detonation Engine with Elevated Initial Pressures written by Andrew George Naples and published by . This book was released on 2008 with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: An experimental study was done to examine the effects of elevated initial tube pressure in the PDE. Measured parameters were the ignition time, DDT run-up distance, DDT times, and C-J velocity. Mixed with air, three fuels, i.e., aviation gasoline, ethylene, and hydrogen, were tested at various initial pressures and equivalence ratios. A stock automotive ignition system was employed, along with a transient and thermal plasma ignition system, to quantify the benefits of each. Measured results show a reduction in the ignition time of roughly 50% and in the DDT distance of roughly 30%, for all three fuels at an initial tube pressure of 3 atmospheres. At roughly 2 atmospheres of initial pressure the thermal plasma ignition system showed no benefit over the stock automotive ignition system. In addition to the experimental results, a brief Chemkin analysis was done to model the stock automotive ignition system.
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Download or read book Characterization of Transient Plasma Ignition Flame Kernel Growth for Varying Inlet Conditions written by and published by . This book was released on 2009 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pulse detonation engines (PDEs) have the potential to significantly improve the efficiency of a variety of internal combustion engine designs. This efficiency improvement hinges on the ability of the engine to detonate fuel/air mixture through deflagration-to-detonation transitions at 60 to 100 times a second. A major breakthrough in reducing the cycle time of a pulse detonation device is through the use of a Transient Plasma Ignition (TPI) system vice the normal Capacitive Discharge Ignition (CDI) system. The TPI system deposits an equivalent amount of energy as the CDI system but in a fraction of the time and over a larger combustor volume. The TPI also creates high quantities of OH due to the high density of energetic electrons produced by the TPI event. The combination of decreased energy deposition time, larger ignition volume, and a high density of free radicals reduces the flame kernel growth time, which in turn creates a choked flame condition more rapidly. This thesis characterized the flame kernel growth following a transient plasma ignition event for various combustor inlet configurations so as to better understand the flame patterns within the combustion chamber. High-speed images of the combustor were taken from a side profile and end view to observe the flame growth. Time from ignition event until initial flame kernel observation and from ignition event until fully developed flame were gathered from the images and plotted to find the most favorable inlet condition.
Download or read book Compact High Power Repetitive Pulsed Power Instrumentation written by and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The vacuum system, pulse generator and oscilloscopes are used for pseudospark-BLT switch research. The pumping system is for achieving necessary high vacuum conditions. Observations of cell membrane perturbation in real time with sub-nanosecond time resolution is made possible by the PicoStar HR-12 CCD camera system and its custom table purchased under this AFOSR Grant. This High-Speed CCD camera system is a component of AFOSR-supported Transient Plasma Ignition research as well. The scopes and pulse generator provide diagnosis, analysis, and control of experiments requiring accurate, fast diagnostics. Implementation of these systems has enabled results in pulsed power switching, and applications of pulsed power to biology, and ignition and combustion. Switching research includes investigation of small BLT switches for compact pulse generation, which will reported this year at an AFOSR MURI review, and technical meetings including the Intl. Conf. on Plasma Science. Biology includes real-time observation of Ca bursts in human lymphocytes, reported in Biophysical and Biochemical Research Communications, and at other reviews and conferences. Ignition includes development of transient plasma ignition, which reduces delays to ignition in applications such as pulse detonation engines.
Download or read book Evaluation and Selection of an Efficient Fuel Air Initiation Strategy for Pulse Detonation Engines written by and published by . This book was released on 2005 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rapid and efficient initiation of hydrocarbon/air mixtures has been identified as one of the critical and enabling technologies for Pulse Detonation Engines (PDEs). Although the NPS Rocket Propulsion Laboratory has successfully demonstrated fuel/air detonations in a valveless pulse detonation engine using ethylene, propane, and JP-10 fuels, past engine designs have relied upon a sensitive fuel/oxygen initiator unit. To realize the increased thermodynamic efficiencies of PDEs and thus compete with ramjets and other supersonic platforms, it is imperative to eliminate any need for supplementary oxygen in an air-breathing PDE design. This thesis examined ignition technologies and initiator designs which did not require auxiliary oxygen, including capacitive discharge systems and the developing technology of Transient Plasma Ignition (TPI). The current NPS pulse detonation engine architecture was modified to evaluate the various ignition strategies in a PDE operating on an ethylene/air mixture at simulated supersonic cruising conditions. Comparisons were based upon ignition success rate, ignition delay time, detonation wave speed, and Deflagration-to-Detonation (DDT) distance. Reliability and performance of the TPI system proved to be superior to conventional ignition systems. Furthermore, successful initiation of a PDE operating at a frequency of up to 40 hertz was demonstrated without the use of supplementary oxygen.
Download or read book Advances in Energy and Combustion written by Ashwani K. Gupta and published by Springer Nature. This book was released on 2021-08-07 with total page 597 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides state-of-the-art advances in several areas of importance in energy, combustion, power, propulsion, environment using fossil fuels and alternative fuels, and biofuels production and utilization. Availability of clean and sustainable energy is of greater importance now than ever before in all sectors of energy, power, mobility and propulsion. Written by internationally renowned experts, the latest fundamental and applied research innovations on cleaner energy production as well as utilization for a wide range of devices extending from micro scale energy conversion to hypersonic propulsion using hydrocarbon fuels are provided. The tailored technical tracks and contributions from the world renowned technical experts are portrayed in the respective field to highlight different but complementary views on fuels, combustion, power and propulsion and air toxins with special focus on current and future R&D needs and activities. The energy and environment sustainability require a multi-pronged approach involving development and utilization of new and renewable fuels, design of fuel-flexible combustion systems that can be easily operated with the new fuels, and develop novel and environmentally friendly technologies for improved utilization of all kinds of gas, liquid and solid fuels. This volume is a useful book for practicing engineers, research engineers and managers in industry and research labs, academic institutions, graduate students, and final year undergraduate students in Mechanical, Chemical, Aerospace, Energy and Environmental Engineering.
Download or read book 41st AIAA ASME SAE ASEE Joint Propulsion Conference Exhibit 10 13 July 2005 Tucson Arizona 05 3750 05 3799 written by and published by . This book was released on 2005 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Efficient Transient Plasma Ignition and Combustion written by and published by . This book was released on 2004 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transient plasma discharges utilizing short (30 to 100 nsec), spatially distributed streamers energized by pulsed power were investigated as a potential new method for flame ignition. Experimental results showed shorter ignition delay and pressure rise time (typically by a factor of 3 for methane-air mixtures), as well as higher maximum pressure compared to conventional spark ignition. In all cases significant modification of initial combustion chemistry appeared to be occurring, leading to more effective combustion over a wider range of pressures and fuel composition rates.
Download or read book A Multi cylinder Transient Plasma Ignition System for Increased Efficiency and Reduced Emissions in Gas Engines written by Dan Singleton and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development and Demonstration of a Production intent Transient Plasma Ignition System for High Efficiency Natural Gas Engines written by Jason Sanders and published by . This book was released on 2020 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Progress in Combustion Diagnostics Science and Technology written by Paul Medwell and published by MDPI. This book was released on 2020-03-25 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: The role that combustion plays in the world’s energy systems will continue to evolve with the changes in technological demands. For example, the challenges that we face today are more focused on the conservation of energy and addressing environmental concerns, which together necessitate cleaner and more efficient combustion processes using a range of fuel sources. This book includes contributions to highlight the recent progress in theory and experiments, development, and demonstration of technologies and systems involving combustion processes, for the production, storage, use, and conservation of energy.
Download or read book Combustion Processes in Propulsion written by Gabriel Roy and published by Butterworth-Heinemann. This book was released on 2006 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical propulsion comprises the science and technology of using chemical reactions of any kind to create thrust and thereby propel a vehicle or object to a desired acceleration and speed. Cumbustion Processes in Propulsion focuses on recent advances in the design of very highly efficient, low-pollution-emitting propulsion systems, as well as advances in testing, diagnostics and analysis. It offers unique coverage of Pulse Detonation Engines, which add tremendous power to jet thrust by combining high pressure with ignition of the air/fuel mixture. Readers will learn about the advances in the reduction of jet noise and toxic fuel emissions-something that is being heavily regulated by relevant government agencies. Lead editor is one of the world's foremost combustion researchers, with contributions from some of the world's leading researchers in combustion engineering Covers all major areas of chemical propulsion-from combustion measurement, analysis and simulation, to advanced control of combustion processes, to noise and emission control Includes important information on advanced technologies for reducing jet engine noise and hazardous fuel combustion emissions
Download or read book Investigation of Microwave Cavity Applicators for Plasma Assisted CVD Diamond Synthesis and Plasma Assisted Combustion written by Kadek Wardika Hemawan and published by . This book was released on 2010 with total page 710 pages. Available in PDF, EPUB and Kindle. Book excerpt:
