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Showing 1 to 20 of 113 for “"Propellants"”.
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Reactions of centralite in aged propellants
… from thermally aged double- and triple-base propellants containing centralite, as well as the nitrocellulose and pierite residues from the latter, by means of two-dimensional thin-layer chromatography and electronic absorption spectroscopy. A second purpose was to obtain material balances for …
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Simplified Combustion Modeling of Composite Propellants
… observed trends for typical composite propellants are replicated. For example, the relative protrusion/recession of oxidizer and binder, recognized as an important feature of propellant surface topography, is correctly predicted. The simulation demonstrates the relation between …
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Random Sphere Packing Model of Heterogeneous Propellants
… of analysis of the morphology of heterogeneous propellants is developed which uses the concept of multi-point correlation functions. A set of intrinsic length scales of local density fluctuations in random heterogeneous propellants is identified by performing a Monte-Carlo study of the …
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Oscillatory Behavior of Fine AP/HTPB Composite Propellants
… of wide distribution AP/HTPB composite propellants containing coarse AP and fuel-rich, fine-AP/HTPB pocket regions has been investigated experimentally and theoretically. These propellants are of special interest because they are similar to many wide distribution bi-modal tailorable …
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Investigation on Ammonium Perchlorate Based Electrically Controlled Propellants
An experimental study exploring the ignition behavior of an electrically controlled gel monopropellant (ECGP) composed of an ionically conducting liquid polymer (polyethylene glycol) and ammonium perchlorate (AP) was conducted. Complexation of AP with PEG enabled ion transport when a voltage was …
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The analysis of rocket propellants by carbon-13 NMR
Polybutadienes, polymerized via free radical mechanism to give an average molecular weight of 3000, were analyzed with carbon-13 NMR. The relative abundance of the three types of structural units (cis-1,4, trans-1,4, and vinylic-1,2 units) was quantitatively determined. The distribution of the …
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Thermomechanical Meso-Scale Modeling of Combustion of Heterogeneous Solid Propellants
In the final part of this dissertation, the coupled thermomechanical and propellant surface regression solver is further enhanced through addition of fluid-phase equations for transport of chemical species and temperature. A simple three-step kinetics model is used to describe the complex reactions …
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Low flux radiative ignition studies of ammonium perchlorate composite propellants
… of aluminized and non-aluminized AP based propellants. A piece of blackened aluminum foil was bound to the top of the propellant to simulate the rocket motor casing and the propellant-metal interface. Once ignition time data and temperature profiles were collected, theoretical models were …
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Fundamental experiments on electrospray propulsion: Propellants, plumes, and material interactions
Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2026-05-01
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Cooling performance of storable propellants for a micro rocket engine
This thesis studies the selection of propellants for a liquid regeneratively cooled micro rocket engine focusing on the characterization of their cooling performance. Propellants will be at high pressures and under high heat fluxes in the cooling passages and will be supercritical. A summary of the …
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Exploration and Development of Electrically Controllable Gel and Solid Propellants
Electrically controllable propellants (ECPs) provide a new method to increase the control and functionality of rocket motors in particular solid rockets. Traditional solid rockets do not have the capability to modify the burning rate on demand during operation, which greatly limits operational …
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Measurement and Modeling of Pressure -Driven Transient Burning of Solid Propellants
… models, applicable to fine oxidizer composite propellants, are examined. The ""surface accumulation model"" supposes that components accumulate in a layer at the surface. Each component reaches an equilibrium concentration inversely proportional to its burning rate. The ""double reaction layer …
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XPS and Carbon-13 NMR spectroscopic analysis of composite rocket propellants
In this study the applicability of Carbon-13 NMR and XPS to the detection of chemical changes in a solid composite rocket propellant was studied. Storage at elevated temperatures was used to simulate the propellant ageing process. In the XPS analysis, changes in the sources for the N(1s) and Cl(2p) …
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Comparison of Cation-Anion Oxidizer Pairings in Electrically Controllable Solid Propellants
Electrically controllable solid propellants are an area of interest as a viable solution to the lack of throttle-ability in solid propellant rocket motors. Existing studies have focused on propellants compositions using hydroxyl-ammonium nitrate, ammonium nitrate, or lithium perchlorate as …
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Methods and analyses for evaluation of erosive burning in solid propellants
… models for erosive burning in composite propellants were reviewed. The experimental techniques which were cited in the literature for the measurement of erosive burning were also reviewed. Only the high-speed motion picture technique was found to have resolution sufficiently high to …
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Nitrosation reactions of sym-diethyldiphenylurea and stabilizer degradation in double-base propellants
… the action of this substance as a stabilizer for propellants. A second aim was to determine the content of centralite and its derivatives in the nitrocellulose residues (obtained from aged double-base propellants), by means of thin-layer chromatographic and spectrophotometry methods. Another aim …
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The effect of radiative heat feedback on burning rate of metalized propellants
Restriction data tranferred 2014-07-01T11:27:36-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission
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In Situ Flame Structure Imaging of Composite Propellants using High-Speed Planar Laser-Induced Fluorescence
… the most commonly used oxidizer in solid rocket propellants due to its availability, high oxygen balance, and combustion characteristics. Models of AP composite propellants have been made since the 1950s and have become highly advanced in recent years. However, experimental data have not kept …
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Modifying burning rate and agglomeration size in aluminized composite solid propellants using mechanically activated metals
… (CMDB) and ammonium perchlorate (AP) composite propellants. However, the ignition temperature is larger than the comparable mechanically activated (MA) Al-Mg powder.</p> <p>Mechanical milling was performed on magnalium powders and modifications of structure and morphology of the alloy during …
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