Download or read book Modeling and Experiments of Laser induced Ignition of Nitramine Propellants written by S. J. Ritchie and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling Laser induced Ignition of Nitramine Propellants with Condensed and Gas phase Absorption written by Yeong-Cherng Liau and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Probes of Propellant Combustion Chemistry written by David R. Crosley and published by . This book was released on 1987 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laser-induced fluorescence (LIF) can be used to measure the small (diatomic and triatomic) free radicals and other transient species that are intermediates in combustion chemistry. LIF can be coupled with detailed computer models of the chemical reaction networks that incorporate a consistent set of reaction rate constants. Doing so leads to an understanding of that chemistry, of predictive value to describe the combustion under conditions difficult to probe experimentally. This report describes the development of LIF techniques, their applications to flames and laser/pyrolysis (LP) kinetics experiments, and rate constant estimation studies for detailed combustion chemistry modeling. The systems studied were those of hydrocarbons burning in nitrous oxide. These contain some of the chemical networks, individual reactions, and intermediate species present in the gas-phase combustion of nitramine propellants such as HMX and RDX.
Download or read book Nitramine Propellant Ignition and Combustion Research New Tools and New Directions written by and published by . This book was released on 1989 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: The efficient and successful design of new generations of highly energetic propellants based on evolving nitramine chemistry will require a thorough knowledge of the chemical and physical parameters controlling their ignition and combustion. The necessary level of insight can be attained and successfully embodied in the predictive computer models necessary for effective propellant design, development and testing activities if a coordinated, hierarchical program of theoretical modeling and confirming and supporting experiments is designed and properly executed. This paper reviews the current state of our understanding of the chemistry and physics of nitramine propellant ignition and combustion and develops and motivates the basic research program necessary to put advanced nitramine propellant development on a firm and effective scientific basis. Confronting and solving problems involving complex physicochemical phenomena which intertwine complex heat, mass and radiative transfer processes with chemical kinetics is a challenge which physical and engineering scientists are becoming much more adept at meeting. Modern theoretical and experimental tools are now available which allow the design and utilization of much more comprehensive analytical models as well as their concomitant supporting and confirming experimental measurements. Gun propellants, Rocket propellants, LOVA propellants, Solid propellants, RDX, HMX.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1995 with total page 1208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 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 31st AIAA ASME SAE ASEE Joint Propulsion Conference and Exhibit written by and published by . This book was released on 1995 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Ignition of Nitramine Composite Propellants written by Jong Uck Kim and published by . This book was released on 1988 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Laser Ignition of Nitramine Composite Propellants and Crack Propagation and Branching in Burning Solid Propellants written by and published by . This book was released on 1987 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two major tasks performed during the report period of investigation were: (i) laser ignition of nitramine-based composite propellants using a high- powered CO2 laser in (ii) crack propagation and branching in burning solid propellants. The laser ignition of a series of RDX-based composite propellants was studied theoretically and experimentally. A comprehensive model for the radiative ignition of the nitramine composite propellants was formulated. The theoretical model was solved numerically. A radiative ignition test setup employing a high-powered CO2 laser was designed and constructed to study ignition characteristics of a series of RDX-based nitramine composite propellants. Interactions between the infrared laser beam and nitramine composite propellants revealed a number of interesting processes. The laser ignition of composite propellants involves many complex thermophysiochemical processes including gasification, initiation of a luminous flame, propagation of the flame, and chemical reactions near the sample surface as well as heat conduction in solid phases. In general, the delay time based upon the onset of light emission decreases monotonically with the increase of incident laser energy flux. Keywords:Ignition, Carbon dioxide laser, Nitramine, Composite propellants, Thermal decomposition, Reaction mechanisms, Ignition delay, Radiation ignition, Crack propagation, Crack branching, Interrupted burning, Depressurization, Extinguishment.
Download or read book Laser Ignition of Solid Propellants 1 Ignition Delays written by and published by . This book was released on 1993 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ignition experiments on nitrate-ester and nitramine propellants have been conducted in a closed bomb. The ignition source was a variable (
Download or read book Research in Progress written by and published by . This book was released on 1988 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nitramine Smokeless Propellant Research written by N. S. Cohen and published by . This book was released on 1977 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: A transient ballistics and combustion model is derived to represent the closed vessel experiment that is widely used to characterize propellants. The model incorporates the nitramine combustion mechanisms which are contained within the steady-state model developed as a part of last year's (FY 1976) research. A computer program is developed to solve the time-dependent equations, and is applied to explain aspects of closed vessel behavior. It is found that the rate of pressurization in the closed vessel is insufficient at pressures of interest to augment the burning rate by time-dependent processes. In the case of nitramine propellants, however, the cratering of the burning surface associated with combustion above break-point pressures augments the effective burning rate as deduced from the closed vessel experiment. Low pressure combustion is significantly affected by the ignition process and, in the case of nitramine propellants, by the developing and changing surface structure. Thus, burning rates deduced from the closed vessel experiment may of may not agree with those measured in the equilibrium strand burner. Application of the model to closed vessel test cases shows good agreement between theory and experiment. Series of T-burner experiments are performed to compare the combustion instability characteristics of nitramine (HMX)-containing propellants and ammonium perchlorate (AP) propellants. It is found that the inclusion of HMX consistently renders the propellant more stable. Although ash produced by more fuel-rich propellants could have provided mechanical suppression, results from clean-burning propellants permit the conclusion the HMX reduces the acoustic driving.
Download or read book Journal of Thermophysics and Heat Transfer written by and published by . This book was released on 2006 with total page 996 pages. Available in PDF, EPUB and Kindle. Book excerpt: This journal is devoted to the advancement of the science and technology of thermophysics and heat transfer through the dissemination of original research papers disclosing new technical knowledge and exploratory developments and applications based on new knowledge. It publishes papers that deal with the properties and mechanisms involved in thermal energy transfer and storage in gases, liquids, and solids or combinations thereof. These studies include conductive, convective, and radiative modes alone or in combination and the effects of the environment.
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 Modeling of Laser Induced Metal Combustion written by and published by . This book was released on 2008 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experiments involving the interaction of a high-power laser beam with metal targets demonstrate that combustion plays an important role. This process depends on reactions within an oxide layer, together with oxygenation and removal of this layer by the wind. We present an analytical model of laser-induced combustion. The model predicts the threshold for initiation of combustion, the growth of the combustion layer with time, and the threshold for self-supported combustion. Solutions are compared with detailed numerical modeling as benchmarked by laboratory experiments.
Download or read book Analytical Investigation of the Combustion Processes Occurring in Advanced Nitramine Based Propellants written by R. N. Kumar and published by . This book was released on 1974 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes a theoretical investigation of the current problems of nitramine (composite) propellant combustion. This study has a detailed examination of the condensed-phase processes in the combustion of nitramine propellants. As a consequence of a recently developed model for the combustion of ammonium perchlorate (AP)/composite propellants, it is hypothesized that the condensed-phase degradation of the nitramine oxidizer particles to a vaporizable state is the overall rate-limiting step. It is also assumed that the gas-phase details are secondary in importance and need be studied only to the extent of supplying the correct boundary conditions on the condensed-phase/vapor-phase heat transfer. Because of an imprecise understanding of the gas-phase processed in the presence of combustion, several plausible models are considered for the gas phase. All of the gas-phase models considered lead to predictions sufficiently close to experimental trends to conclude that precise details of gas-phase processes are not of critical importance in determining propellant combustion behavior. It is believed that a thorough examination of the condensed-phase details may be sufficient in itself not only to interpret most of the available data on experimental regression rate vs. pressure of nitramine propellants, but also to aid in the formulation of propellants needed.
