Download or read book Chemical Kinetics of Gas Phase Decomposition Products of Nitramine Propellants written by M. C. Branch and published by . This book was released on 1984 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitramine based solid rocket propellants have the advantages of relatively low infrared and smoke emissions from their exhaust. Although a number of studies have been directed toward chemical and physical processes in the condensed phase during heating or combustion, the understanding of gas phase chemical processes has not been developed. The objective of the studies reported here is to provide additional insight into the chemistry of reactions of gas phase species of importance in the combustion of nitramine propellants. Chemical kinetic modeling of the gas phase reactions is used to evaluate critical reaction paths and energetic and their possible influence on burn rate. Particular attention has been given to the fizz reaction near the propellant surface and the preparation and flame zones standing off the surface. The chemical kinetic modeling shows a two zone behavior which is consistent with previous suggestions about the chemistry of the fizz and flame zones. The first zone is dominated by the rapid between CH20 and NO2 while the second zone results from the slower exothermic reduction of NO.

Download or read book Chemical kinetics of nitramine propellant combustion written by and published by . This book was released on 1988 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many solid rocket propellants and other energetic materials consist of complex chemical compounds of carbon, hydrogen, oxygen and nitrogen. The decomposition of these solid reactants leads to the formation of gaseous hydrocarbons and oxides of nitrogen which can react to support a flame above the surface of the solid. These flames can provide heat which is fed back to the propellant surface and thereby influence the burning rate of the solid. In the case of nitramine based solid rocket propellants, the gas phase decomposition products include significant amounts of Ethyloxide, Hydrogen cyanide, Nitrogen dioxide, Nitric oxide, Nitrous oxide and Oxygen. This study is intended to provide experimental data on the structure of hydrocarbon flames supported by oxides of nitrogen in order to establish the reaction mechanism for such flames. Laminar, premixed, flat flames of Methane/NO2/O2 and CH2O/NO2/O2 have been investigated and a reaction mechanism is suggested which accounts for all of the major observations in the data.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 542 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chemical Kinetic Investigation of the Thermal Decomposition of Energetic Materials written by Tanusree Chatterjee and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Energetic materials such as propellants which are burned to produce thrust in applications like guns, rockets/space propulsion systems, automobile air bags and ejection seats of airplanes, play a critical role in meeting the performance and safety requirements by generating high pressure within a short duration of time. Propellants used in practical applications, generally consists of two or more energetic ingredients. To ensure that the above-mentioned devices are well designed, it is critical to understand the thermal decomposition (or combustion) behavior of energetic ingredients that comprise the propellants. It is also of paramount importance to understand the chemistry involved during decomposition of these energetic ingredients which will enable a knowledge-based improvement and engineering of propellants. In this dissertation using synergistic application of experimental and computational methods, three different energetic materials are studied: Ammonia borane (AB); Ammonium perchlorate (AP) and HMX-TAGzT. Ammonia borane (AB) is a hypergolic rocket fuel used in liquid propellants and a potential hydrogen storage medium. Although several studies have been undertaken over the years to understand the chemical kinetics involved during AB decomposition, it is still not well understood. The reaction pathways developed so far are primarily based on the experimental observations of a limited set of chemical species and there exists no consensus. In this work, a detailed AB reaction mechanism was developed using thermolysis experiments and quantum mechanics (QM) calculations to explain the formation of species observed during experiments, reconciling the existing conflicts regarding the initiation step, as well as the pathways of H2 formation during decomposition. The developed reaction mechanism not only explains the experimental observations, but also provides information which are difficult to obtain only by performing experiments. Ammonium perchlorate (AP) is one of the most common oxidizers used in solid composite propellant. Owing to high-pressure deflagration limit (PDL) and very fine structure of AP flame, minimal amount of experimental data is available till today. Hence, numerical simulations play critical role in order to understand the combustion phenomenon of AP monopropellants. Although existing combustion models use detailed reaction mechanism for gas phase, chemical kinetics involved in AP melt layer or condensed phase is still modeled using global/semi-global reactions which is one of the major stumbling blocks in modeling AP combustion. In this work, a liquid phase reaction mechanism for perchloric acid (HClO4) decomposition is proposed based on QM calculations. HClO4 which is one of the primary sublimation products of AP is experimentally observed during the ignition and combustion of AP (NH4C1O4)-containing solid propellants in both gas and condensed phase. Hence, this work can be viewed as a first step towards development of detailed liquid-phase reaction mechanism for AP combustion modeling. HMX is a nitramine-based high-explosive fuel which is often used in solid composite propellants to increase energy output and TAgzT is commonly used as burn rate enhancer for nitramine-based propellants. Although significant amount of work has been done to understand the thermal decomposition behavior of HMX and TAGzT as a monopropellant, the interaction of these two energetic materials was not studied previously. In this work, using thermolysis experiments (TGA/DSC coupled with FTIR spectroscopy), thermal decomposition characteristics of HMX-TAGzT mixtures at low and moderate temperatures (373-673 K) using low heating rates (

Download or read book Chemical Kinetics of the Gas Phase Combustion of Fuels written by Francis Westley and published by . This book was released on 1976 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Work supported by the Office of Standard Reference Data, National Bureau of Standards, Naval Sea Systems Command, Department of the Navy, and Division of Conservation, Research and Technology, Energy Research and Development Administration.

Download or read book Chemical Kinetics of Nitramine Propellants written by Melvyn Branch and published by . This book was released on 1986 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper describes experimental measurements of the structure of a lean, premixed, laminar, flat flame of methane/nitrogen oxide/oxygen. The composition of stable species in the flame was measured by a cooled quartz sampling microprobe and gas chromatographic analysis. The composition of the intermediates CN, Ch, NH and NH2 was measured by laser-induced fluorescence spectroscopy using an excimer laser pumped tunable dye laser system. The flame has two luminous zones, one yellow and the other violet, separated by distinct, dark nonluminous zones. The concentration of NO2 has a maximum in the yellow zone while the concentrations of CN, NH, NH2 and NO are maximum in the violet region. The CH concentration profile has two peaks with one occuring in the yellow and one in the violet luminous zone. THe first peak is thought to be due to Ch4/02 reactions while the second peak is attributed to CH4/NO2 reactions. The oxidation of Ch4 is supported by the decomposition of NO2 to NO, although 02 is important in the initiation of the reaction process.

Download or read book Solid Propellant Chemistry Combustion and Motor Interior Ballistics 1999 written by Vigor Yang and published by AIAA. This book was released on 2000 with total page 1038 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Chemistry and Physics of Energetic Materials written by S.N. Bulusu and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 756 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book represents a collection of lectures presented at the NATO Advanced study Institute(ASI) on "Chemistry & Physics of the Molecular Processes in Energetic Materials", held at Hotel Torre Normanna, Altavilla Milicia, Sicily, Italy, September 3 to 15, 1989. The institute was attended by seventy participants including twenty lecturers, drawn from thirteen countries. The purpose of the institute was to review the major ad vances made in recent years in the theoretical and experi mental aspects of explosives and propellants. In accordance with the format of the NATO ASI, it was arranged to have a relatively small number of speakers to present in depth, re view type lectures emphasizing the basic research aspects of the subject, over a two week period. Most of the speakers gave two lectures, each in excess of one hour with addition al time for discussions. The scope of the meeting was limit ed to molecular and spectroscopic studies since the hydro dynamic aspects of detonation and various performance crite ria of energetic materials are often covered adequately in other international meetings. An attempt was made to have a coherent presentation of various theoretical, computational and spectroscopic approaches to help a better understanding of energetic materials from a molecular point of view. The progress already made in these areas is such that structure property (e. g.

Download or read book Research in Progress written by and published by . This book was released on 1992 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book AIAA 28th Aerospace Sciences Meeting written by and published by . This book was released on 1990 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Critical Analysis of Nitramine Decomposition Data written by Michael A. Schroeder and published by . This book was released on 1985 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is currently considerable interest in the use of nitramine oxidizers in gun and rocket propellants due to their desirable properties, such as absence of noxious combustion products, high specific impulse and impetus, and thermal stability. The most commonly used nitramine oxidizers are RDX (also known by such names as hexogen or cyclonite) and HMX. (Octogen). A literature review is presented, on kinetic parameters for thermal decomposition of HMX and RDX in the homogeneous vapor, liquid, and dissolved states. The decomposition apparently fits first-order kinetics, and suggested values for Arrhenius parameters for HMX and RDX decomposition in the gaseous and liquid phases, and for decomposition of RDX in solution in TNT are given. The possible importance of autocatalysis is pointed out as are some possible complications that may be encountered in interpreting, extending or extrapolating kinetic data for these compounds from measurements carried out below their melting points to the higher temperatures and pressures characteristic of combustion. The mechanistic implications of the activation energies and frequency factors are discussed. Keywords: Statistical analysis; Vapor phase decomposition; Neat liquid.

Download or read book Thermal Decomposition Pathways in Nitramine Propellants written by Frank J. Lovas and published by . This book was released on 1995 with total page 19 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 1999 with total page 1016 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Overviews Of Recent Research On Energetic Materials written by Donald L Thompson and published by World Scientific. This book was released on 2005-08-02 with total page 531 pages. Available in PDF, EPUB and Kindle. Book excerpt: Few books cover experimental and theoretical methods to characterize decomposition, combustion and detonation of energetic materials. This volume, by internationally known and major contributors to the field, is unique because it summarizes the most important recent work, what we know with confidence, and what main areas remain to be investigated. Most chapters comprise summaries of work spanning decades and contain expert commentary available nowhere else. Although energetic materials are its focus, this book provides a guide to modern methods for investigations of condensed and gas-phase reactions. Although these energetic reactions are complex and difficult to study, the work discussed here provides readers with a substantial understanding of the behavior of materials now in use, and a predictive capability for the development of new materials based on target properties.

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1991 with total page 1380 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1989 with total page 1458 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 698 pages. Available in PDF, EPUB and Kindle. Book excerpt: