Engineering topics
Publications and source records attributed to Rosenberg, Sanders D..
Iridium-coated rhenium combustion chamber withstands operating temperatures up to 2,200 degrees C. Chamber designed to replace older silicide-coated combustion chamber in small rocket engine. Modified versions of newer chamber could be designed for use on Earth in gas turbines, ramjets, and scramjets.
Two rocket engines that operate at temperature of 2,500 K designed to provide thrust for station-keeping adjustments of geosynchronous satellites, for raising and lowering orbits, and for changing orbital planes. Also useful as final propulsion stages of launch vehicles delivering small satellites to low orbits around Earth. With further development, engines used on planetary exploration missions for orbital maneuvers. High-temperature technology of engines adaptable to gas-turbine combustors, ramjets, scramjets, and hot components of many energy-conversion systems.
The Aerojet Carbothermal Process for the manufacture of oxygen from lunar resources has three essential steps: the reduction of silicate with methane to form carbon monoxide and hydrogen; the reduction of carbon monoxide with hydrogen to form methane and water; and the electrolysis of water to form oxygen and hydrogen. This cyclic process does not depend upon the presence of water or water precursors in the lunar materials; it will produce oxygen from silicates regardless of their precise composition and fine structure. Research on the first step of the process was initiated by determining some of the operating conditions required to reduce igneous rock with carbon and silicon carbide. The initial phase of research on the second step is completed; quantitative conversion of carbon monoxide and hydrogen to methane and water was achieved with a nickel-on-kieselguhr catalyst. The equipment used in and the results obtained from these process studies are reported in detail.
The Aerojet carbothermal process for the manufacture of oxygen from lunar materials has three essential steps: the reduction of silicate with methane to form carbon monoxide and hydrogen; the reduction of carbon monoxide with hydrogen to form methane and water; and the electrolysis of water to form hydrogen and oxygen. The reactions and the overall process are shown. It is shown with laboratory experimentation that the carbothermal process is feasible. Natural silicates can be reduced with carbon or methane. The important products are carbon monoxide, metal, and slag. The carbon monoxide can be completely reduced to form methane and water. The water can be electrolyzed to produce hydrogen and oxygen. A preliminary engineering study shows that the operation of plants using this process for the manufacture of propellant oxygen has a large economic advantage when the cost of the plant and its operation is compared to the cost of delivering oxygen from Earth.
Space transportation requirements for the NASA baseline scenario for future space missions are discussed. Spacecraft/propulsion technologies required for surface-to-orbit, orbit-to-orbit, and surface (lunar) transportation are addressed.
Experimental data validating advanced engine designs at three thrust levels (5, 15, and 100 lbF) is presented. All of the three engine designs considered employ a Moog bipropellant torque motor valve, platelet injector design, and iridium-lined rhenium combustion chamber. Attention is focused on the performance, robustness, duration, and flexibility characteristics of the engines. It is noted that the 5- and 15-lbF thrust engines can deliver a steady state specific impulse in excess of 310 lbF-sec/lbm at an area ratio of 150:1, while the 150-lbF thrust engines deliver a steady state specific impulse of 320 lbF-sec/lbm at an area ratio of 250:1. The hot-fire test results reveal specific impulse improvements of 15 to 25 sec over conventional fuel film cooled columbium chamber designs while operating at maximum chamber temperatures.
The formation and deposition of carbon (soot) was studied in the Carbon Deposition Model for Oxygen-Hydrocarbon Combustion Program. An empirical, 1-D model for predicting soot formation and deposition in LO2/hydrocarbon gas generators/preburners was derived. The experimental data required to anchor the model were identified and a test program to obtain the data was defined. In support of the model development, cold flow mixing experiments using a high injection density injector were performed. The purpose of this investigation was to advance the state-of-the-art in LO2/hydrocarbon gas generator design by developing a reliable engineering model of gas generator operation. The model was formulated to account for the influences of fluid dynamics, chemical kinetics, and gas generator hardware design on soot formation and deposition.