Download or read book Deflagration to Detonation Transition Study Using Simultaneous Schlieren and OH PLIF Images written by S.-Y. Lee 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 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 Shock Waves written by Zonglin Jiang and published by Springer Science & Business Media. This book was released on 2010-05-30 with total page 1346 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 24th International Symposium on Shock Waves (ISSW24) was held at the Beijing Friendship Hotel during July 11-16, 2004, in Beijing. It was a great pleasure for the Local Organizing Committee to organize the ISSW in China for the first time, because forty-seven years have passed since the First Shock Tube Symposium was held in 1957 at Albuquerque. The ISSW24 had to be postponed for one year because of the SARS outbreak in Beijing shortly before the Symposium was scheduled to be held in 2003, but it has achieved success due to the continuous support and kind understanding from all the delegates. It is very heart-warming to have had such an experience and I am very happy to have served as chairman for the Symposium. I would like to thank all for the contributions and help that they have given us over the past three years, without which we would not have had the Symposium. A total of 460 abstracts were submitted to the ISSW24. Each of the abstracts was evaluated by three members of the Scientific Review Committee and the decision on acceptance wasmade based on the reviewers' reports. 195oral papers,including 9plenary lectures, wereaccepted to be presented in three parallel sessions, and 135poster papers in three dedicated poster sessions. Topics discussed in these papers cover all aspects ofshock wave research.

Download or read book 36th AIAA ASME SAE ASEE Joint Propulsion Conference Exhibit 2000 3200 2000 3249 written by and published by . This book was released on 2000 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Turbulence compressibility Dynamics of Fast Flames for Turbulence Induced Deflagration to detonation written by Jessica Chambers and published by . This book was released on 2021 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the fundamental mechanisms for detonation initiation is turbulence induced deflagration-to-detonation transition (tDDT). This research experimentally explores the dynamics of highly turbulent fast flames that are characterized by extremely high turbulent flame speeds, experience increased effects of compressibility, and may develop a runaway acceleration combined with a pressure buildup that leads to tDDT. The flame dynamics and reacting flow field are characterized using simultaneous high-speed particle image velocimetry, OH* chemiluminescence, pressure measurements, and schlieren imaging. We study various regimes of fast flame propagation conditions for runaway acceleration of turbulent fast flames and effects of compressibility on the evolution of these flames. When the local measured turbulent flame speed is found to be greater than the Chapman-Jouguet deflagration speed, the flame is categorized to be at the runaway transition regime that eventually leads to a detonation.

Download or read book Flame generated Turbulence for Flame Acceleration and Detonation Transition written by Rachel Hytovick and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detonations are a supersonic mode of combustion witnessed in a variety of applications, from next-generation propulsion devices to catastrophic explosions and the formation of supernovas. Detonations are typically initiated through the deflagration to detonation transition (DDT), a detailed process where a subsonic flame undergoes rapid acceleration increasing compressibility until a hotspot forms on the flame front inciting a detonation wave to form. Due to the complex nature of the phenomena, DDT is commonly investigated in three stages -- (i) preconditioning, (ii) detonation onset, and (iii) wave propagation and stability. The research presented explores each of these stages individually, with a focus on preconditioning, to further resolve the governing mechanisms needed to initiate and sustain a detonation. More specifically, this work seeks to investigate the flow field and flame characteristics in reactions with increasing compressibility. Additionally, the research examines detonation onset and wave propagation to attain an all-encompassing concept of the DDT process. The work uses simultaneous high-speed diagnostics, consisting of particle image velocimetry (PIV), OH* chemiluminescence, schlieren and pressure measurements, to experimentally examine the preconditioning stage. For detonation onset and propagation, megahertz diagnostics (OH* chemiluminescence and schlieren) are implemented to quantitatively visualize the supersonic event. Through the comprehensive suite of diagnostics, this research deduces the role of turbulence in detonation onset to an ongoing cycle of flame generated compression that amplifies until the hotspot ignites.

Download or read book 40th AIAA Aerospace Sciences Meeting Exhibit written by and published by . This book was released on 2002 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 40th AIAA ASME SAE ASEE Joint Propulsion Conference Exhibit July 11 14 2004 Fort Lauderdale FL 04 3350 04 3399 written by and published by . This book was released on 2004 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 39th AIAA ASME SAE ASEE Joint Propulsion Conference Exhibit July 20 23 2003 Huntsville Alabama 03 4950 03 4999 written by and published by . This book was released on 2003 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization of Fast Flames for Turbulence induced Deflagration to Detonation Transition written by Jessica Marcella Chambers and published by . This book was released on 2018 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the fundamental mechanisms for detonation initiation is turbulence driven deflagration to detonation transition (TDDT). The research experimentally explores the propagation dynamics demonstrated by fast deflagrated flames interacting with highly turbulent reactants. Fast flames produce extremely high turbulent flame speeds values, increased levels of compressibility and develop a runaway mechanism that leads to TDDT. The flame structural dynamics and reacting flow field are characterized using simultaneous high-speed particle image velocimetry, chemiluminescence, and Schlieren measurements. The investigation classifies the fast flame propagation modes at various regimes. The study further examines the conditions for a turbulent fast flame at the boundary of transitioning to quasi-detonation. The evolution of the flame-compressibility interactions for this turbulent fast flame is characterized. The local measured turbulent flame speed is found to be greater than the Chapman–Jouguet deflagration flame speed which categorizes the flame to be at the spontaneous transition regime and within the deflagration-to-detonation transition runaway process.

Download or read book AIAA Aerospace Sciences Meeting and Exhibit 42nd written by and published by . This book was released on 2004 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chemical and Physical Processes in Combustion written by Combustion Institute (U.S.). Eastern States Section. Fall Technical Meeting and published by . This book was released on 2001 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Simultaneous Formaldehyde PLIF and High speed Schlieren Imaging for Ignition Visualization in High pressure Spray Flames written by and published by . This book was released on 2013 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book AIAA Journal written by American Institute of Aeronautics and Astronautics and published by . This book was released on 2003 with total page 1252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1997 with total page 684 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Enhancement of Deflagration to detonation Transition Via Distributed Photo ignition written by Daniel J. Finigan and published by . This book was released on 2011 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of Deflagration to Detonation Transition in a Pulsed Detonation Engine written by David Michael Chapin and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A Pulse Detonation Engine (PDE) is a propulsion device that takes advantage of the pressure rise inherent to the efficient burning of fuel-air mixtures via detonations. Detonation initiation is a critical process that occurs in the cycle of a PDE. A practical method of detonation initiation is Deflagration-to-Detonation Transition (DDT), which describes the transition of a subsonic deflagration, created using low initiation energies, to a supersonic detonation. This thesis presents the effects of obstacle spacing, blockage ratio, DDT section length, and airflow on DDT behavior in hydrogen-air and ethylene-air mixtures for a repeating PDE. These experiments were performed on a 2 diameter, 40 long, continuous-flow PDE located at the General Electric Global Research Center in Niskayuna, New York. A fundamental study of experiments performed on a modular orifice plate DDT geometry revealed that all three factors tested (obstacle blockage ratio, length of DDT section, and spacing between obstacles) have a statistically significant effect on flame acceleration. All of the interactions between the factors, except for the interaction of the blockage ratio with the spacing between obstacles, were also significant. To better capture the non-linearity of the DDT process, further studies were performed using a clear detonation chamber and a high-speed digital camera to track the flame chemiluminescence as it progressed through the PDE. Results show that the presence of excess obstacles, past what is minimally required to transition the flame to detonation, hinders the length and time to transition to detonation. Other key findings show that increasing the mass flow-rate of air through the PDE significantly reduces the run-up time of DDT, while having minimal effect on run-up distance. These experimental results provided validation runs for computational studies. In some cases as little as 20% difference was seen. The minimum DDT length for 0.15 lb/s hydrogen-air studies was 8 L/D from the spark location, while for ethylene it was 16 L/D. It was also observed that increasing the airflow rate through the tube from 0.1 to 0.3 lbs/sec decreased the time required for DDT by 26%, from 3.9 ms to 2.9 ms.