Download or read book Model for Steady State Combustion of Unimodal Composite Solid Propellants written by Merrill K. King and published by . This book was released on 1978 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: A model for prediction of burning rate-pressure-crossflow velocity relationships for non-metalized composite propellants containing unimodal oxidizer, given only composition and oxidizer particle size, has been developed. This model embodies many of the concepts used in the Beckstead-Derr-Price model, but contains major modifications, including a postulated columnar diffusion flame bending mechanism for erosive burning. The major part of this paper is devoted to description and discussion of these modifications and to model development. Preliminary predictions of burning rate at various pressures and crossflow velocities have been made for a series of three 73/27 ammonium perchlorate (AP)/hydroxy-terminated-polybutadiene (HTPB) formulations, with oxidizer particle diameters of 5, 20, and 200 microns, and compared with data for these formulations. With optimization of three 'free constants' appearing in the model, it is found to give excellent agreement with no-crossflow burning rate data over the entire range of pressures and particle sizes studied. In all cases, however the predicted sensitivity of burning rate to crossflow velocity is somewhat less than observed experimentally. (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 Steady State Combustion of Nonmetallized Composite Solid Propellant written by R. L. Glick and published by . This book was released on 1975 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: Monodisperse BDP combustion model was extended to nonmetallized propellants with mixed, polydisperse oxidizers by embedding monodisperse model in statistical framework including mixture ratio effects. Basically, polydisperse propellant is 'disassembled and rearranged' to form sequence of monodisperse pseudo-propellants whose rates are computed via monodisperse model. Reassembly provides real propellant's burning rate. Approach provides information pertaining to distribution of regression rates and surface structure among different size oxidizer particles. Preliminary results suggest that significant factor in rate increases wrought by introduction of small oxidizer modes is mixture ratio alternations in larger modes. Hydraulic T-burner analog was constructed and employed to visualize vent flow phenomena. Studies showed that flow enters vent with axial momentum and that momentum is partially transformed to vent into Karman vortex sheet. Fact that flow enters vent with axial momentum invalidates boundary condition of Culick analysis for flow turning gain; 'correct' boundary condition leads to null vent gain. Experimental facts consistent with proof that in formal one-dimensional flow vent gain violates second law of thermodynamics. Logical and consistent way to reduce solid rocket data when pressure-time history is not neutral was derived. Since current techniques are not self-consistent in this situation, these results open door to reclamation of performance data heretofore rejected. (Author).
Download or read book Statistical Analysis of Steady State Combustion of Composite Solid Propellants written by R. L. Glick and published by . This book was released on 1978 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: A general method for extracting particle size dependent information from experimental rate/formulation data was developed from the statistical methodology. This technique was employed to correlate the data bases of Miller. Results showed that, by employing an interaction parameter of 4, both additive and additive free data could be correlated to standard error of estimate below 10.5%. The effect of steady radiant energy deposition on steady and nonsteady burning was explored. Results showed that if the radiant energy deposited in the reactive zones is negligible (an excellent assumption for low signature propellants) the effect of radiant energy deposition can always be accounted for by substituting the radiation augmented initial temperature for the initial propellant temperature.
Download or read book Effects of Steady state Acceleration on Combustion Characteristics of an Aluminized Composite Solid Propellant written by G. Burton Northam and published by . This book was released on 1968 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Investigation of the Steady State Burning of Ammonium Perchlorate Composite Solid Propellants written by Job S. Ebenezer and published by . This book was released on 1973 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new, comprehensive steady-state model describing the burning of non-metalized, unimodal ammonium perchlorate (AP)-polymeric composite solid propellant has been developed and shown to yield better results than previous models. This new model incorporates a near-surface AP decomposition flame perturbed by fuel vapor diffusion (after Chaiken) followed by a granular diffusion flame (after Summerfield), and is termed the 'modified granular diffusion flame' (MGDF) model. The MGDF model permits numerical prediction of the influence of pressure, AP particle size, mixture ratio and propellant initial temperature on propellant burning rate. While the new model has proven notably successful, evaluation of the capabilities of it and other models is constrained by the limited existing data base. (Modified author abstract).
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1984 with total page 1200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Statistical Analysis of Steady State Combustion of Nonmetallized Composite Solid Propellants written by R. L. Glick and published by . This book was released on 1977 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: The combustion model including aluminum and iron oxide was employed to correlate data bases of Miller and Maykut. Results for additive free formulations were excellent for both rate and exponent; results for formulations with aluminum and aluminum plus iron oxide were poor. A new method for extracting particle size dependent information from rate/response function/formulation data was developed from the statistical methodology itself and employed to process the aforementioned data bases. Results were encouraging; Miller's additive free and aluminum plus iron oxide data correlated very well; Miller's aluminum data showed that the increasing aluminum particle size increases interactions between oxidizer modes; Maykut's data base showed that aluminum induced interactions among oxidizer modes are decreased as iron content increases. Results elucidate mechanisms for rate, exponent, and response function control and show that the equal rate hypothesis employed in much combustion modeling is incorrect. A new approach for including the effects of transients introduced by particle size dependent rates in both steady and nonsteady combustion modeling was conceived. (Author).
Download or read book Combustion Response Calculations for Composite Solid Propellants written by J. P. Renie and published by . This book was released on 1981 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this report, the theoretical, steady state combustion model, the Petite Ensemble Model (PEM), is described in detail. The PEM is based upon a combination of a unique statistical treatment of the burning propellant surface and a comprehensive multiple flame type, physio-chemical combustion model. Due to this statistical treatment, the PEM can account for both oxidizer particle size and oxidizer particle size distribution effects on burning rate behavior; an unique feature of this model. The effects on propellant burning rate behavior due to the inclusion of aluminum particles have been taken into account within this version of the PEM, as have any possible effects caused by the presence of a crossflow velocity above the propellant surface (erosive burning). The PEM is capable of modeling the burning behavior of AP-based/hydrocarbon binder, composite solid propellants. Propellant additives such as aluminum oxide, zirconium carbide and graphite, as well as aluminum, can also be incorporated in the propellant formulations modeled by the PEM. This report presents the results obtained by applying a small perturbation analysis to the equations representing the steady state PEM (including aluminum and erosive burning effects). Performing such an analysis yields nonsteady state models of both the pressure coupled response and the velocity pressure coupled response of composite solid propellants. Other historical pressure coupled response models such as the Dension and Baum mode, the Cohen model, and the Zeldovich/Novozhilov model are also briefly described. Finally, a second velocity coupled response model based on the Zeldovich/Novozhilov methodology coupled to the erosive burning PEM is presented. (Author).
Download or read book Combustion Response Modeling for Composite Solid Propellants written by Norman S. Cohen and published by . This book was released on 1978 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this program was to develop a computerized mathematical model of the combustion response function of composite solid propellants, with particular attention to the contributions of the solid phase heterogeneity. A one-dimensional model was developed which treats the solid phase as alternating layers of AP and binder, with an exothermic melt layer at the surface. Solution of the Fourier heat equation in the solid provides temperature and heat flux distributions with space and time. The problem is solved by equating the heat flux at the surface to that produced by a suitable model of the gas phase. An approximation of the BDP flame model is utilized to represent the gas phase. By the use of several reasonable assumptions, it is found that a significant portion of the problem can be solved in closed form. A method is presented by which the model can be applied to tetramodal particle size distributions. A computerized steady-state version of the model was completed, which served to validate the various approximations and lay a foundation for the combustion response modeling. It is concluded that some other mechanism associated with the propellant heterogeneity must be incorporated into the theory to account for observed behavior.
Download or read book Theory of Solid Propellant Nonsteady Combustion written by Vasily B. Novozhilov and published by John Wiley & Sons. This book was released on 2020-09-15 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite significant developments and widespread theoretical and practical interest in the area of Solid-Propellant Nonsteady Combustion for the last fifty years, a comprehensive and authoritative text on the subject has not been available. Theory of Solid-Propellant Nonsteady Combustion fills this gap by summarizing theoretical approaches to the problem within the framework of the Zeldovich-Novozhilov (ZN-) theory. This book contains equations governing unsteady combustion and applies them systematically to a wide range of problems of practical interest. Theory conclusions are validated, as much as possible, against available experimental data. Theory of Solid-Propellant Nonsteady Combustion provides an accurate up-to-date account and perspectives on the subject and is also accompanied by a website hosting solutions to problems in the book.
Download or read book 16th JANNAF Combustion Meeting Naval Postgraduate School Monterey California September 10 14 1979 Nitramine and solid rocket propellants ramjets and liquid bipropellants unclassified written by and published by . This book was released on 1979 with total page 706 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:
Download or read book Some Research Problems in the Steady State Burning of Composite Solid Propellants written by D. W. Blair and published by . This book was released on 1960 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper outlines a number of basic problems in the theory of steady-state combustion of solid propellants, particularly of the ammonium perchlorate composite type. It represents an extension of the earlier research at Princeton that led to a theoretical burning rate law for composite propellants that was based on the concept of granular diffusion flame. This paper is in the nature of a progress report in which the new experimental approaches are described, and some puzzling difficulties are analyzed. Specifically, the experiments deal with three topics: refinement of methods for measuring burning rate; the role of radiative energy transfer in the burning process; and the connection between oxidizer particle size and the b parameter in the above-mentioned theoretical burning rate law.
Download or read book A Continuous Oxidizer Regression Model for the Combustion of Composite Solid Propellants written by Joseph John Cor and published by . This book was released on 1987 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past several decades, there has been a considerable effort to model the process occurring during the combustion of composite solid propellents. Accurate models able to predict the burning rate characteristics of solid propellents would be very valuable, as they would facilitate the design of solid rocket fuels by reducing the need for laboratory testing of different solid mixtures until a mixture with the right ballistic properties is found. Using a reliable analytical model, a propellent designer could, in theory, simply input key properties of a possible propellent formulation into the model, and the model would provide an accurate prediction of what the burning rate characteristics for the mixture would be. Earlier attempts at modeling the steady-state burning of composite solid propellents are reviewed, with an emphasis placed on the Beckstead, Derr, and Price (BDP) and Petite Ensemble Model (PEM). The Continuous Oxidizer Regression (COR) model is then described, which is a modification to the PEM model. The COR model's predictions for burning rate and pressure exponent are then compared to those of an actual solid composite propellent. The model predicts the general trends found in actual experimental data, but the model's output is found to be highly sensitive to the assumptions regarding surface geometry and flame formation, which are as yet not clearly known.
Download or read book Modeling the Steady state Combustion of Solid Propellant Ingredients with Detailed Kinetics written by Karthik V. Puduppakkam and published by . This book was released on 2003 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Combustion Response Calculations for Composite Solid Propellants Volume II User s Manual written by J. P. Renie and published by . This book was released on 1981 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume II is a user's manual for computer programs written to perform theoretical analyses described in Volume I. This volume describes the main routines and subroutines used in the analysis of the combustion of composite solid propellants both steady state and nonsteady state. Also, a detailed description of the input parameters required as well as the output generated is presented. Sample cases are provided to facilitate understanding of the programs so described. (Author).
