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Showing 1 to 20 of 299 for “"propellant"”.
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On-Orbit Cryogenic Propellant Storage Optimization
<p>The optimization of an on-orbit Cryogenic Propellant Storage (CPS) system enables human exploration missions by reducing launch vehicle mass to orbit requirements and providing an extensible approach for human spaceflight missions to near-Earth asteroids, the moon, and Mars. The optimal CPS …
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Comprehensive Computational Modeling of Hypergolic Propellant Ignition
<p>Ignition and combustion of hypergolic propellants mono-methyl hydrazine (MMH) and red fuming nitric acid (RFNA) is investigated computationally. A hierarchical approach is chosen to study parametric behavior of isolated processes and complex interactions thereof, in this transient phenomenon. …
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Composite propellant combustion with low aluminum agglomeration
… polybutadiene (AP/HTPB) propellant formulation that results in low Al agglomeration, even at low pressures (1-30 atm). Variations in formulation—such as fine-AP/binder ratio, Al particle size, Al loading, coarse-AP size—are also examined. A fuel-rich, oxygenated binder …
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Towards Electrical Control Over Rocket Propellant Combustion
Electrical control over propellant combustion has the opportunity to improve the functionality and performance of various propulsion systems. In solid rocket motors, active burn rate modulation has the potential to enable throttling. In spacecraft propulsion systems, electrolysis of propellants may …
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Maneuvering Control of a Spacecraft with Propellant Sloshing
<p>Propellant slosh has been a problem studied in spacecraft designs since the early days of large, liquid-fuel rockets. The conventional design solution involves physical structures inside the fuel tanks that limit propellant motion. Although effective, baffles and bladders add to spacecraft mass …
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Minimization of Roll Firings for Optimal Propellant Maneuvers
… conditions with the goal of minimizing total propellant. An ISS simulation too was then used to test these solutions for feasibility. After several problem reformulations, multiple candidate solutions minimizing or completely eliminating roll firings were found. Flight implementation would not …
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Solid propellant slow cookoff experiments with advanced diagnostics
Slow cookoff of solid propellant was experimentally studied at the University of Illinois by examining the behavior throughout the cookoff process. The general concept involved preparing axial-symmetric samples of chosen compositions and casting them into carbon fiber cases. The cured samples were …
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Thermal stresses in a finite solid-propellant grain
… gain a fundamental understanding of actual solid propellant thermal stress problems, the geometry of the solid propellant baa been idealized as a short, circular cylinder with flat ends. It is felt that the consideration of actual curved ends would only unduly have complicated the analysis. The …
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Quantitative analysis of rocket propellant by capillary gas chromatography
The analysis of nitrate-ester propellants and explosives has been performed extensively by gas chromatography for the past decade. As capillary GC technology has advanced, new opportunities for the improvement of existing methods have developed. This investigation probes several of these …
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Investigations into deep cracks in rocket motor propellant models
… surface cracks are detected in the rocket motor propellants, the mechanism of these cracks is sull not well known due to the complex geometry of the grain. A stress-freezing photoelastic investigation has been performed to study the deep cracks which emanate from the fingertips of the star-shaped …
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DEVELOPMENT OF INNOVATIVE BURN RATE ADDITIVES FOR DOUBLE BASE PROPELLANT
… 1940s that the addition of lead to double-base propellants, resulted in beneficial burn rate phenomena. However, due to its toxicity the Department of Defense has been trying to find a replacement for lead over the last decade. Research efforts with this goal in mind have generally used the same …
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Characterization of a green electric solid propellant for electric propulsion
<p>"Electric solid propellants are advanced solid chemical rocket propellants that can be controlled (ignited, throttled and extinguished) through the application and removal of an electric current. These propellants are also being considered for use in ablative pulsed plasma thruster and multimode …
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Investigating Energetic Porous Silicon as a Solid Propellant Micro-Thruster
… energetic porous silicon as a viable solid propellant for propulsion of nano-satellites and micro-robots.
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Investigation of the Manufacturing Variables of Cast Double-base Propellant
The casting of double-base propellant involves the filling with liquid of a mould packed with solid particles. Simultaneous mass transfer between the phases, known as gelation, retards the flow, hindering the prediction of casting time. A mathematical model to predict casting times is developed via …
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Radiative heat transfer from aluminum oxide in solid propellant flames
The radiative heat transfer in aluminized propellant flames was determined. Liquid aluminum oxide (Al$\sb2$O$\sb3$) particles, produced from the distributed combustion of aluminum droplets, dominated the optical characteristics of aluminized propellant flames. A laser scattering and extinction …
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Lunar lander propellant production for a multiple site exploration mission
… surface with the capability of producing its own propellant to launch itself to multiple sites of scientific interest. It is compared with two other possible planetary exploration architectures: the multiple mission architecture which sends one mission to each landing site of interest, and the …
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Study of Hybrid Magneto-Active Propellant Management Device for Slosh Damping
… for many decades and many novel inventions in Propellant Management Devices (PMDs) such as the rigid baffles and elastomeric membranes have been implemented to counteract the free surface effect in both passive and active membrane known as Magneto-Active Propellant Management Device (MAPMD) to …
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Investigation into continuous spray and metered spray using compressed gas propellant
… the domestic aerosol products use hydrocarbon propellants (i.e. butane and propane) in which a high flash vaporisation provides a good atomisation. However, according to the 2015 United Nations Climate Change Conference agreed in Paris, these propellants have the adverse climatic effects due to …
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