Download or read book Coupling Between Velocity Oscillations and Solid Propellant Combustion written by R. S. Brown and published by . This book was released on 1982 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: A literature survey of velocity coupling found that existing analytical models do not predict instability reliably. Manifestations of velocity coupling in burners and motors are described in the literature as harmonic content and mean shift in pressure traces and susceptibility to triggering instability by pulsing. Evidence of these phenomena were found in numerous laboratory burners, research motors, and development motors. The motors which exhibited velocity coupling all had a large L/D ration. The severity of instability was found to depend on the propellant composition, grain geometry, nozzle geometry, and propellant conditioning temperature. A cold flow simulated rocket motor with porous walls has been constructed. Oscillatory heat flux at the wall has been measured in this simulated motor while driving pressure oscillations with a rotating valve. (Author).
Download or read book Solid propellant Combustion Instability and the Role of Velocity Coupling written by Louis A. Povinelli and published by . This book was released on 1969 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pressure and velocity coupling effects on combustion stability in solid propellant burning.
Download or read book Coupling Between Acoustic Velocity Oscillations and Solid Propellant Combustion written by R. S. Brown and published by . This book was released on 1986 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fluid mechanics of the coupling between acoustic waves and the solid propellant combustion have been studied in a cold flow simulation of a solid propellant rocket motor. The axial variation of the oscillatory heat flux shows substantial deviations from the behavior expected from both the linear and nonlinear heuristic models of velocity coupling that are currently used in combustion stability analyses. Keywords: solid propellants, combustion, acoustics, instability.
Download or read book Nonlinear Combustion Instability in Solid Rocket Motors A Numerical Study of Longitudinal Oscillations with Pressure and Velocity Coupling written by Joseph D. Baum and published by . This book was released on 1982 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: An existing nonlinear instability model has been extended and improved to allow it to more realistically treat the longitudinal shock wave type of combustion instability frequently encountered in tactical solid rocket motors. Results obtained utilizing this model to investigate limiting amplitude and velocity coupling phenomena in solid rocket motors are presented. An advanced finite difference integration technique capable of accurately describing shocks and contact discontinuities has been incorporated into the computer program, as well as an improved heat conduction solution, an heuristic velocity coupling model, and a spectral analysis capability. Solutions of wave propagation and shock formation and propagation in a variable area duct and a solid propellant rocket motor are presented; as are a number of solutions demonstrating that limiting amplitude is independent of the characteristics of the initial disturbance. Results of a preliminary study of nonlinear velocity modulated limit cycles are presented, as are results that demonstrate the primarily traveling wave nature of nonlinear wave propagation in solid rocket motors, and the complexity of the phase relationships between pressure, burning rate, and velocity oscillations are presented. Finally, the effect of a threshold velocity on non-linear velocity coupled instability was explored, and some of the results are also presented. (Author).
Download or read book Solid propellant Combustion Instability and the Role of Velocity Coupling written by Louis A. Povinelli and published by . This book was released on 1969 with total page 49 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 1988 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
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 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 Combustion Instabilities In Solid Propellant Rocket Motors written by and published by . This book was released on 2004 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Velocity Coupling Analysis written by M. D. Horton and published by . This book was released on 1972 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report describes the results of a phenomenological study of the interaction between acoustic velocities and solid propellant combustion. The test apparatus used in the study was a T-burner, adapted to permit high speed cinemicrography coverage of a propellant test sample placed at the center of the T-burner where the acoustic velocity is at a maximum. A driver propellant (usally JPN) was used to provide a hot, oscillatory environment for the tests. Over 100 tests were performed with nine different propellant formulations. The frequency of oscillation, mean pressure, acoustic pressure amplitude, mean erosive velocity, and acoustic velocity were test variables. (Author).
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1987 with total page 934 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Combustion Theory written by Forman A. Williams and published by CRC Press. This book was released on 2018-03-05 with total page 549 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combustion Theory delves deeper into the science of combustion than most other texts and gives insight into combustions from a molecular and a continuum point of view. The book presents derivations of the basic equations of combustion theory and contains appendices on the background of subjects of thermodynamics, chemical kinetics, fluid dynamics, and transport processes. Diffusion flames, reactions in flows with negligible transport and the theory of pre-mixed flames are treated, as are detonation phenomena, the combustion of solid propellents, and ignition, extinction, and flamibility pehnomena.
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 Analysis of Combustion Oscillations in Heterogeneous Systems written by M. Ben-Reuven and published by . This book was released on 1984 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study is aimed at elucidation of the physical mechanisms capable of driving acoustic instability in solid propellant rocket motors, of the type termed velocity-coupled instability. The first and second tasks of this research, Critical Literature Review, and Order of Magnitude Analyses of velocity-coupling mechanisms, have been reported earlier. The third part of the study, Analytical Simulation of the Interior Flowfield Within a Solid Propellant Grain, is reported herein. The subject of the present analysis is simulation of the cold-flow experiments by Dr. Brown at UTC/CSD, in which nitrogen is injected through the porous sidewalls of a cylindrical pipe, creating an internal axisymmetric flow field. A comprehensive analytical model of the nonsteady flow processes entails a system of four partial differential equations for continuity, radial and axial momentum and thermal enthalpy. The flowfield is considered compressible and viscous, with all of the dissipative terms included. A focal point of the analysis has been the thin viscous sublayer adjacent to the porous surface, where visco-acoustic interactions occur. Additional keywords: mathematical models; combustion stability; numerical analysis; computations; heat transfer; and perturbations.
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 558 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Solid propellant ignition and unsteady combustion processes written by Leonard H. Caveny and published by . This book was released on 1976 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research carried out under the grant was aimed at furthering the scientific understanding of nonsteady propellant combustion behavior in rocket motor chambers. Controlled nonsteady flow and burning conditions were produced in laboratory-scale solid rocket motors by developing a device that modulated the throat area of the primary nozzle. Modulation frequencies up to 2400 Hz were obtained. The modulated throat rocket motor is being used to acquire data using AP composite propellant grains. Cold flow tests were used to study the acoustic modes and nozzle discharge characteristics. Computerized techniques were developed for conducting spectral analyses of head-end and nozzle-end pressure data. In addition, the equations describing the nonsteady one-dimensional gas dynamics and propellant combustion were formulated, and a comprehensive numerical solution was developed. The present solution takes into account the couplings among the oscillating nozzle flow, the nonsteady chamber flow, and erosive burning. Since pressure and velocity oscillations can be made to occur and decay in high loading density rocket motors with realistic grain configurations, the experiment is expected to produce propellant/chamber response functions that are relatively easy to interpret, compared to the difficult to interpret T-burner response functions.
Download or read book Development of a Computerized Analysis for Solid Propellant Combustion Instability with Turbulence written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-02 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: A multi-dimensional numerical model has been developed for the unsteady state oscillatory combustion of solid propellants subject to acoustic pressure disturbances. Including the gas phase unsteady effects, the assumption of uniform pressure across the flame zone, which has been conventionally used, is relaxed so that a higher frequency response in the long flame of a double-base propellant can be calculated. The formulation is based on a premixed, laminar flame with a one-step overall chemical reaction and the Arrhenius law of decomposition with no condensed phase reaction. In a given geometry, the Galerkin finite element solution shows the strong resonance and damping effect at the lower frequencies, similar to the result of Denison and Baum. Extended studies deal with the higher frequency region where the pressure varies in the flame thickness. The nonlinear system behavior is investigated by carrying out the second order expansion in wave amplitude when the acoustic pressure oscillations are finite in amplitude. Offset in the burning rate shows a negative sign in the whole frequency region considered, and it verifies the experimental results of Price. Finally, the velocity coupling in the two-dimensional model is discussed. Chung, T. J. and Park, O. Y. Unspecified Center NAG8-627...
