Download or read book Cars Spectroscopy of Propellant Flames written by and published by . This book was released on 1983 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Broadband coherent anti-stokes Raman scattering (CARS) spectra were obtained from both the reaction zone and postflame regions of CH(4)/N(2)O flames. The temperature and concentration profiles obtained from both N(2) and N(2)O flames were used to understand the elementary processes occurring in CH(2) /N(2) flames. In addition, N(2) and CO vibrational spectra were used to obtain concentration and temperature profiles by a least-square fit to model calculations. The results obtained were in accord with thermochemical calculations. In rich CH(4)/N(2)O flame previously unobserved, CARS spectra were obtained from pure rotational H(2) transitions. These H(2) spectra offer further opportunities for studying propellant systems. The characterization of CARS spectroscopy obtained from these studies was used to obtain initial CARS measurements from the reaction zone of nitramine composite propellant flames. These studies are only possible using a coherent, highly spatially, and temporally resolved spectroscopy such as CARS. These qualities of CARS which have been applied to the deflagration of propellants containing the explosive ingredients nitrocellulose and/or RDX can be used to study the decomposition and explosive reactions of other energetic materials in both the gas and solid phases.
Download or read book Laser Spectroscopy of Propellant Like Flames written by Richard A. Beyer and published by . This book was released on 1983 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: The laser-based techniques Coherent Anti-Stokes Raman Spectroscopy (CARS) and Spontaneous Raman Scattering have been applied to studies of the detailed chemistry of premixed flames. The status of this research effort and its future goals in gun propulsion research are discussed. (Author).
Download or read book Cars Spectroscopy of Gun Propellant Flames Higher Hot Band and Concentration Effects written by L. E. Harris and published by . This book was released on 1982 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrogen Coherent Anti-Stokes Raman Scattering (CARS) spectra from nitrate-ester propellant flames contain several features not reported in nitrogen CARS spectra from other flames. Prominent among these features is a high intensity peak (30% maximum) 30 cm( -1) to the low energy side of the first hot band. Nitrogen CARS spectra from air/argon mixture containing from 1% to 30% air changed substantially with concentration but agreed with calculated spectra to better than 6%. Nitrogen CARS spectra from propane/air flames of various equivalence ratios showed a resolved second hot band, Q(32) at 2,269 cm( -1) and the presence of the third hot band, Q(43), near 2,241 cm( -1). Temperatures determined from Q(32) agreed, within experimental error, with those determined with Q(10) at 2,296 cm( -1). Temperature trends for the various equivalence ratios agreed with thermochemical predictions, allowing the accuracy to be assessed at better than 5%. The good agreement of nonplanar and planar BOXCARS validated the earlier planar BOXCARS measurements. Nitrogen CARS calculations agreed well with experimental propellant spectra at the 10% nitrogen concentration expected from thermochemical calculations. The calculated spectra show the presence of Q(32) near 30% maximum intensity as seen in the propellant spectra.
Download or read book CARS Coherent Anti Stokes Raman Scattering Spectroscopy of the Reaction Zone of Methane Nitrous Oxide and RDX Propellant Flames written by L. E. Harris and published by . This book was released on 1986 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: CARS spectra were obtained for a phi = 3.2 CH4/N20 model and nitramine propellant flames throughout the reaction and post-flame zones in order to assess kinetic mechanisms occurring in these flames. The reaction zone of the rich CH4/N20 flame was studied primarily to provide a stationary flame analog to the transient propellant flame. In the CH4/N20 flame, the decay of the initial products was observed through the Q-branch of the nu 1 and nu 3 modes of N20 and the Q, O and S branches of nu 2 and 2 nu 2 modes of CH4. The formation of the products N2, H2 Q(v' = 0 and v' = 1) and S(5) - S(9), and CO2 were also observed. Temperatures were obtained from both the H2 and N2 Q-branches. In the nitramine propellant flame, the upper bound of the gas-surface interface temperature was measured as 900 K + or - 100 K from the H2 Q-branch. Near the surface of the propellant, reactant RDX (1599 cm-1 tentatively assigned as asymetric NO2 stretch) and transients HCN (NU1) and NO are observed as moderate concentration (> or = 1%). The final product N2 is observed at low concentration, (approx. 1%), H2 (Q and S beaches) and CO are observed at higher concentration (> or = 10%). RDX and HCN decay within 2 mm of the propellant surface while NO remains constant until 4 mm where it decays with a concommitant rise in N2 concentration and temperature. H2 and CO also increase in temperature and concentration.
Download or read book CARS Spectroscopy of Gun Propellant Flames written by L. E. Harris and published by . This book was released on 1981 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Temperature measurements were made in a slightly fuel rich, premixed, propane/air reference flame and nitrate ester propellant flames burning in air at atmospheric pressure using Coherent Anti-Stokes Raman Scattering (CARS). Both single and multiple-pulse CARS nitrogen spectra in the reference flame agreed with model spectra and the derived temperature agreed with sodium line reversal values. Single pulse CARS nitrogen spectra obtained in the propellant flames were analyzed to give temperatures consistent with the values calculated using the NASA-Lewis thermochemical calculation. Comparison of a 0.1-second separated sequence of single pulse CARS spectra indicated turbulent air mixing in these propellant flames. The results demonstrated that temporal and spatially resolved temperature measurements could be determined in transient, turbulent flames. (Author).
Download or read book Nonsteady Burning and Combustion Stability of Solid Propellants written by Martin Summerfield and published by AIAA. This book was released on 1992 with total page 922 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Theoretical Calculations of H 2 CARS Spectra for Propellant Flames written by J. Fendell and published by . This book was released on 1983 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: High energy pure rotational H(2) CARS transitions have recently been observed in several spectral regions, most notably, the NO and CO CARS regions. H(2) CARS is of interest because hydrogen is a major combustion product of propellants, especially nitramine propellants. For this reason, calculations were performed to assign the observed H(2) transitions. For this particular case, the calculations of interest are for the observed S- and Q-branch transitions of H(2) for v equal to 0 and 1. Spectroscopic constants available in the literature and the results of an ab initio calculation performed by Ermler were used in the analysis. Ermler used the potential energy curves for the ground state of hydrogen calculated by Kolos and Wolniewicz over a range of 0.4
Download or read book CARS Studies of Nitramine Lova Propellant Combustion written by K. Aron and published by . This book was released on 1983 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coherent anti-Stokes Raman scattering (CARS) spectroscopy was used to probe the nitramine LOVA flame, burning unconfined in the air. Several spectral regions were scanned in an attempt to document the transient species of the RDX combustion for use in determining decomposition mechanisms.
Download or read book 17th JANNAF Combustion Meeting NASA Langley Research Center Hampton Virginia September 22 26 1980 written by and published by . This book was released on 1980 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Single Shot H 2 Cars Spectroscopy of Propellant Ignition and Combustion Under Pressure written by T. E. Haw and published by . This book was released on 1986 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: A single-shot H(2) CARS spectrometer was developed, and experimental considerations for accurate thermometry were examined. The spectrometer is capable of synchronization with external events such as laser-initiated propellant ignition or ballistic compression, given an inherent delay time of 250 microseconds and a predetermined diagnostic time window approaching 1 second. Additional capability to operate in a double Q-switched mode (two diagnostic probes 60 to 90 microseconds apart) has been demonstrated, with inherent delay time of 190 microseconds. Application to static samples of H(2) and to an H(2)/0(2) flame reveal unreferrence errors approaching 10% or more in temperature determination, and indicate the necessity for simultaneous standardization in accurate thermometry. Intensity determination in an unreferrenced fashion reveals fluctuations of 30%, with contributions from YAG and dye laser intensity and phase fluctuations. Q-branch lines from the first vibrational state (beta = 1) of hydrogen were observed for the first time in the H(2)/0(2) flame using this apparatus. Facilities have been established with which to perform single-shot H(2) CARS diagnostics on propellant ignition and flame under pressure. Preliminary experiments indicate the choice of background gas, flow rates through the pressure cell, YAG laser fluence, and dye laser spectral width are critical factors in the development of a working protocol. CARS spectra of nitrogen product gas pellant flame have been observed.
Download or read book Hybrid Fs ps CARS for Sooting and Particle laden Flames written by and published by . This book was released on 2016 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fast Reactions in Energetic Systems written by Christos Capellos and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 747 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the formal lectures and contributed papers given at the NATO Advanced Study Institute on Fast Reactions in Energetic Systems, which took place in Preveza, Greece, during the period 6-19 July 1980. The material describes experimental observations and the more advanced theoretical aspects of certain types of fast reactions and energy or charge transfer processes which are usually complete 6 12 in periods of 10- - 10- seconds. Furthermore, it discusses the role of macroscopic and molecular processes in the ignition, combustion, deflagration, and detonation of solid, liquid, and gaseous chemical systems. Various papers deal with the ability of molecules to absorb and transmit the different forms of energy provided by shock, light, thermal, or electron pulses, and to contribute to the propagation of reactions under high temperatures and pressures. The role of energy pumped or transferred to electronic or vibrational states is discussed in terms of excitation, ionization, bond scission, and the formation of free radicals. The dynamics and reactivity of ionic species, electronically and vibrationally excited states, and free radicals are described for various gaseous, liquid, and solid systems. The proceedings include presentations of theoretical and experimental techniques to describe and observe the phenomena.
Download or read book Solid Propellant Flame Spectroscopy written by J. T. Edwards and published by . This book was released on 1988 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes the progress made in solid propellant flame chemistry studies. These chemistry studies involved the spectroscopic determination of species concentration and temperature profiles in solid propellant flames at pressures from atmospheric to 7 MPa (1000 psi). The propellants involved contained AP and HMX, as well as several other formulations. The molecules studied were OH, CH, NH, and NO, primarily, although other atomic and molecular species were seen in the propellant flames in emission. The primary diagnostic employed was laser-induced fluorescence (LIF), although the chemiluminescence (emission) from the propellant flames was also studied. These experiments are continuing. Keywords: Models, Combustion diagnostics, Hydrogen oxygen, Carbon, Nitrogen, Chemical radicals. (aw).
Download or read book Energetic Materials written by Ulrich Teipel and published by John Wiley & Sons. This book was released on 2006-03-06 with total page 643 pages. Available in PDF, EPUB and Kindle. Book excerpt: Incorporation of particular components with specialized properties allows one to tailor the end product's properties. For instance, the sensitivity, burning behavior, thermal or mechanical properties or stability of energetic materials can be affected and even controllably varied through incorporation of such ingredients. This book examines particle technologies as applied to energetic materials such as propellants and explosives, thus filling a void in the literature on this subject. Following an introduction covering general features of energetic materials, the first section of this book describes methods of manufacturing particulate energetic materials, including size reduction, crystallization, atomization, particle formation using supercritical fluids and microencapsulation, agglomeration phenomena, special considerations in mixing explosive particles and the production of nanoparticles. The second section discusses the characterization of particulate materials. Techniques and methods such as particle size analysis, morphology elucidation and the determination of chemical and thermal properties are presented. The wettability of powders and rheological behavior of suspensions and solids are also considered. Furthermore, methods of determining the performance of particular energetic materials are described. Each chapter deals with fundamentals and application possibilities of the various methods presented, with particular emphasis on issues applicable to particulate energetic materials. The book is thus equally relevant for chemists, physicists, material scientists, chemical and mechanical engineers and anyone interested or engaged in particle processing and characterization technologies.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Coherent Raman Spectroscopy Applications And New Developments Proceedings Of The Xi European Cars Workshop written by F Castellucci and published by World Scientific. This book was released on 1993-02-09 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: The meeting was a forum on the 'state of the art' of the fundamental aspects and the applications of Coherent Antistokes Raman Scattering (CARS) and related nonlinear optic techniques.This volume contains the works of outstanding scientists from the most distinguished research centers of universities, public and private institutions in Europe and other countries, who work on the theory and application of nonlinear laser spectroscopic techniques to the study of gas combustion kinetics, noninterfering flame temperature measurements, high temperature reactors, plasmas and the exciton and vibrational dynamics in condensed phases.
Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1981 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:
