Abstract: A Perforated-Plate Churn-Mixer (PPCM) is disclosed for a mixing system that is used to efficiently wet and disperse small-particle-size solids into a liquid and then provide a wide range of shear levels to insure the break-up of any remaining agglomerates and the uniformity of the mixture. The PPCM is a device which comprises a mixing vessel and a perforated plate that oscillates within the vessel to force the solids and liquids to pass repeatedly through the perforations in the plate and the clearance between the plate and the walls of the vessel. The perforated plate is attached to a rod that is oscillated by external equipment and passes through an airtight seal in the lid of the vessel. The lid maintains an airtight seal with the parallel walls of the vessel and also has a vent that can be closed.

Abstract: Elemental silicon is a solid high energy material which provides an advane when added to gel, hybrid, and ducted rocket fuels by increasing both specific impulse, lsp, and density specific impulse, .rho.*lsp. The quantity added depends on the specific applications for which the formulation will be used. The usual concentration ranges from about 0.5% to about 70% by weight. The important parameters to consider during formulation are particle size, concentration, combustion efficiency, physical properties, and plume signature. Comparisons for 50% solid fuel loading in a gel bipropulsion system predicts a maximum lsp of 286 lbf.s/lbm as compared to 267 lbf.s/lbm for carbon--a 7% increase. The .rho.*lsp produced by silicon is 14.5 lbf.s/cubic inch as compared to 13.7 lbf.s/cubic inch produced by carbon--a 7% increase. A 25% solid loading in solid fuel-gas generators for the hybrid rocket produced a maximum lsp of 278 lbf.s/lbm as compared to 267 lbf.s/lbm produced by carbon--a 4% increase. The .rho.

Abstract: A propulsion system is disclosed comprising a glycidyl azide polymer (GAP) olid fuel generator (SFGG) that produces fuel-rich hot gases which are combusted in a combustion zone of a combustion chamber of a solid fuel ducted rocket. A basic embodiment comprises an airbreathing engine wherein a ducted member scoops air in from the atmosphere for hypergolic reaction with the fuel-rich hot gases for propulsion during a sustain stage of a flight. An augmentation of the basic embodiment is achieved by combusting the fuel-rich GAP SFGG effluent with inhibited red fuming nitric acid (IRFNA) gel oxidizer to produce higher thrust during the boost and dash stages of a flight. During the high thrust stages, the air ducts of the ducted member are closed and IRFNA gel is injected into the combustion chamber to react with the fuel-rich hot gases from the GAP SFGG.

Abstract: A gel/solid bipropellant propulsion system employs fuel-rich combustion gs from a solid gas generator and an oxidizer gel in a highly efficient combustion chamber wherein the fuel-rich combustion gases and the oxidizer gel are each metered through a vortex injector into a combustion chamber to produce a hypergolic reaction. The solid gas generator (SSG) has a preferred composition of glycidly azide polymer (GAP). The GAP SSG is composed of GAP diol and/or triol polymerized with a di-or tri-function isocyanate, such as isophorone diisocyanate. The gel/solid bipropellant propulsion system comprises the SSG in combination with an oxidizer storage/extrusion vessel system, a combustion chamber system, and a system controller which controls initial ignition of the SSG to produce fuel rich combustion gas which pressurize the system. The system controller monitors pressures and flow rates of fuel and gel oxidizer.