Download or read book An Experimental Investigation of the Burning Rate of Propellant ANB 3066 Under Oscillatory Pressure and Oscillatory Velocity Conditions written by R. D. Gould and published by . This book was released on 1973 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt: A program of work was conducted in order to measure the effects of oscillatory pressure and velocity at a frequency of 800 Hz upon the burning rate of ANB 3066. The burning rate was measured using a microwave interferometer method and also calculated from the pressure/time records of T-burner and KT-motor firings. An empirical relationship was derived which describes the burning rate under oscillatory and non-oscillatory conditions in terms of the average Mach number, the oscillatory pressure and the mean pressure at the propellant surface. (Author).

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1980 with total page 1280 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements written by and published by . This book was released on 1974 with total page 1000 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Journal of Wave material Interaction written by and published by . This book was released on 1992 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Investigation of the Effect of Aluminum Size and Loading on the Burning Rate of Solid Propellants Under Acceleration written by G. Burton Northam and published by . This book was released on 1969 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Studies on the Oscillatory Combustion of Solid Propellants written by NAVAL WEAPONS CENTER CHINA LAKE CA. and published by . This book was released on 1969 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the results of testing a series of composite and double-base propellants in a T-burner facility. The investigation reveals the unstable combustion behavior that is susceptible of excitation under acoustic pressure-coupled conditions. The degree of instability is quantitatively described in terms of the response function, which is a well-defined characteristic of the propellant. The effect of pressure and frequency has been systematically investigated for the frequency range of 500-10,000 cps and for pressures up to nearly 3,000 psia. Such an extended coverage has permitted the determination of a very general pattern of behavior, including the maximum instability conditions, the isoresponse function contours, and the neutral boundary separating the unstable and stable combustion regimes in the 1.5-inch T-burner. (Author).

Download or read book Experimental Investigation of Transverse mode Solid propellant Combustion Instability in a Vortex Burner written by Louis A. Povinelli and published by . This book was released on 1966 with total page 42 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 1977 with total page 1414 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 650 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1996 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Analytical and Experimental Investigation of the Erosive Burning of Composite Propellants written by Merrill K. King and published by . This book was released on 1977 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Augmentation of solid propellant burning rate often occurs in the presence of strong product gas flow across the burning surface: This phenomenon is referred to as erosive burning. Increasing use of motors with low port-to-throat area ratios (including nozzleless motors) is leading to increased occurrence and severity of erosive burning. A first generation model based upon bending of columnar diffusion flames by a crossflow, permitting prediction of the effect of high-velocity crossflow on the burning rate of a composite propellant given only the zero-crossflow burning rate characteristics, is briefly summarized and compared with data. A second generation model (currently under development) which does not require even zero-crossflow burning rate data, using only composition and particle size as input, is outlined. In addition, a test device permitting extensive characterization of burning rate-pressure-crossflow velocity relationships for various propellants with direct continuous measurement of instantaneous burning rate by high-speed cinematography is described, and results of a series of tests with four propellants are presented. These tests indicate that the first generation composite propellant erosive burning model has reasonable good predictive capability, particularly in the higher pressure region where the propellant combustion is dominated by the propellant heterogeneity.

Download or read book Government Reports Index written by and published by . This book was released on 1975 with total page 1074 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Government Reports Annual Index written by and published by . This book was released on 1974 with total page 1064 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Study of Solid Propellant Combustion Instability written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, experimental investigation of solid propellant combustion instability using an end burning T-Burner setup is performed. For this purpose, a T-Burner setup is designed, analyzed, constructed and tested with all its sub components. T-Burner setup constructed is mainly composed of a base part, a control panel and the T-Burner itself. Combustion chamber, pressure stabilization mechanism, pressurization system, measurement instruments and data acquisition systems form the T-Burner. Pressure stabilization mechanism is utilized in two different alternatives, first of which is by the use of nitrogen gas and a small surge tank with a cavitating venturi. This is a brand new approach for this kind of system. The second alternative is the use of a choked nozzle for pressure stabilization. Resonance frequencies of the system with the two different pressure stabilization mechanisms are experimentally evaluated. Helmholtz frequency of the T-burner constructed is calculated and no Helmholtz instability is observed in the system. Constructed T-Burner setup is operated for a specific solid propellant. System worked successfully and pressure data are obtained. Pressure data revealed oscillatory behaviour. Decay and growth rates of pressure oscillations are used for the calculation of pressure response of the propellant tested. By the use of this T-Burner comparison of the behavior of different propellants can be performed. It can be used as a test device for measuring quantitatively the response of a burning propellant to unsteady motions.

Download or read book Experimental Investigation of High Burn Rate Propellant for Use in Nozzle less Boosters written by R. Farinaccio and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Combustion Dynamics of Liquid Droplets and Turbulent Jets Relevant to Rocket Engines written by Miguel Angel Plascencia Quiroz and published by . This book was released on 2021 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: These experiments examined the reactive processes involving nanoparicle laden liquid droplets, and turbulent jet flames as two separate sets of studies. The first part of this dissertation (Chapters 2 and 3) deals with the combustion of ethanol liquid droplets loaded with nano particulate additives using different droplet formation methods. For this study, an apparatus at the Energy and Propulsion Research Laboratory at UCLA was used to keep the droplet in a quiescent environment. Three different types of droplet combustion experiments were performed, involving: (I) the classic single droplet suspended from a quartz fiber, (II) a single droplet suspended from a quartz capillary, (III) a burning droplet that has continual fuel deliver to sustain the droplet for longer periods of time during the combustion process. Two alternative nanoparticles were explored to demonstrate the effect of energetic additives: reactive nano aluminum (nAl) and inert nano silicon dioxide (nSiO2), each having nominal average diameters of 80 nm. Simultaneous high speed visible and OH* chemiluminescence images were taken to determine the shape of the droplet over time and hence the burning rate constant (K), flame standoff distance, and mean OH* chemiluminescence intensity with varying particulate concentrations. Visible imaging showed particle/vapor ejections and jetting in continuously fed droplet experiments, while rod-suspended burning droplets showed limited particle ejection, usually towards the end of the droplet lifetime. The nSiO2-laden, rod-suspended droplets formed a porous, shell-like structure resembling the shape of a droplet at higher nSiO2 concentrations, in contrast to smaller residue structures left for nAl-laden droplets. A systematic increase in the burning rate constant was observed as the loading concentration of nAl was increased from 1wt%-6wt%. The droplet with continual fuel delivery had the greatest improvement in K of 13% over the pure fuel value. For nSiO2, the continuously fed droplet showed the greatest increase of 5% at 1 wt% loading concentrations, and no consistent trend was observed for nSiO2, likely due to the large shell-like residue structures in the latter stages of combustion. Transmission electron microscopy (TEM) images of particle residue revealed additional insights.The second part of this dissertation (Chapters 4 and 5) studied reacting gaseous turbulent jets in a newly constructed experiment at the Air Force Research Laboratory (AFRL/RQR) located at Edwards Air Force base. This experimental study aimed to characterize the coupling of an acoustic field with a turbulent gaseous methane nonpremixed flame under atmospheric pressure conditions. Two separate injection configurations were examined: one that involved a classic single methane jet surrounded by a minimal velocity oxidizer co-flow and a second coaxial jet configuration with annular oxidizer flow and the same low-velocity co-flow. The different jets were placed within an acoustic waveguide in which standing waves could be created using several speakers. The reacting jets could thus be situated at either a pressure node or a pressure anti-node location. High-speed Schlieren and OH* chemiluminescence images recorded the near field behavior of the flame under both unforced and acoustically forced conditions. High-speed imaging showed two different phenomena associated with these standing waves. When the flame was forced while situated at a pressure node, a sinuous oscillatory response of the flame was observed, in addition to transverse oscillations of the center fuel jet, which shortened the intact fuel core length. The flame "flattened" into an ellipsoidal shape in the direction of the acoustic waves. Conversely, at a pressure anti-node, the coupling of the acoustics and flame gave rise to an axisymmetric response (puff-like oscillations), which prompted the flame to become unstable at the anchoring region. This could lead to periodic liftoff or permanent flame liftoff. A receptivity study for a methane jet at Reynolds number of 5,300 and an ambient oxygen concentration of 40\% showed that the reacting jet was able to respond at the frequency of the unsteady acoustic field for a range of frequencies, but with a diminishing response of the flame for both the pressure node and the pressure anti-node under high frequency excitation. Proper Orthogonal Decomposition (POD) analysis was able to extract mode shapes and frequencies based on pixel intensity fluctuations. For the cases of pressure node forcing, this analysis method illustrated the different modes of flame oscillation, in many cases which were similar to corresponding low Reynolds number fuel jet experiments with pressure node excitation conducted at UCLA. A forcing susceptibility diagram was created to map the three different anchoring stability regimes the flame experienced under pressure anti-node forcing, demonstrating the need for higher amplitude excitation required for the flame to lift off when forced at higher frequency pressure anti-node conditions. As an extension to the single jet, the shear coaxial jet configuration kept the center fuel and surrounding oxidizer co-flow constant. Only the outer annular oxidizer flowrate was varied, with annulus-to-inner jet velocity ratios ranging from R = 0.05 to 0.3, to investigate its impact on the flame's ability to respond to the acoustics. In the absence of acoustic excitation, the coaxial jet did demonstrate natural shear layer/wake like instabilities at higher annular-to-jet velocity ratios, for R = 0.17 and 0.3. The dynamical response of the coaxial jet to pressure node excitation exhibited similar characteristics to that of the single jet for a range of forcing frequencies. But when forced at a pressure anti-node, a notable difference between the two configurations was found. The shear coaxial jet was more responsive to the acoustic forcing at higher forcing frequencies, for example, than the single fuel jet. The susceptibility diagrams for the full range of annular-to-inner jet velocity ratios demonstrated opposite trends when compared to the single jet, that is, that the coaxial jet was more responsive to excitation at a given excitation amplitude when the forcing frequency was higher, and thus closer to the natural coaxial jet instability frequency. Hence evidence suggests that the natural instabilities of the coaxial jet shear layer may be causing the difference in susceptibility diagrams. Both sets of experimental studies here, the nanofuel droplet combustion studies and the acoustically-coupled turbulent fuel jet combustion experiments, provide useful advances to our understanding of reactive flows relevant to liquid rocket engine systems. Enhancement in burning rates with nanoparticulate additives show potential benefits for rocket fuels, and attendant benefits are documented in the presence of acoustic disturbances, studied separately [1]. AFRL-based acoustically coupled turbulent fuel jet studies reveal different dynamical characteristics, depending on the injection system and the acoustic frequency and amplitude range. Different characteristic signatures extracted via POD analysis are both relevant in understanding combustion instabilities and in developing reduced order models underlying control of such instabilities. The present studies contribute to these goals in important ways.