Engineering topics
Publications and source records attributed to Richter, R..
A solid electrolyte cell including a body of solid ionized gas-conductive electrolyte having mutually spaced surfaces and on which is deposited a multiplicity of mutually spaced electrodes is described. Strips and of bare substances are interposed between electrodes, so that currents of ionic gas may be established between the electrodes via the bare strips, whereby electrical resistance for the cells is lowered and the gas conductivity is enhanced.
The major design and performance test subtasks in the development of small (200 to 1,000 whr) integral heat pipe/thermal energy storage devices for use with thermally driven spacecraft cryo-coolers are described. The design of the integral heat pipe/thermal energy storage device was based on a quasi steady resistance heat transfer, lumped capacitance model. Design considerations for the heat pipe and thermal storage annuli are presented. The thermomechanical stress and insulation system design for the device are reviewed. Experimental correlations are described, as are the plans for the further development of the concept.
Mission analyses indicated that by extracting oxygen from the Martian atmosphere, which consists primarily of carbon dioxide, the launch mass of a spacecraft can be reduced by such an amount that samples from the planet can be returned to earth. The solid electrolyte process for producing O2 from CO2 was investigated. A model of the thermodynamic and electrochemical processes in the electrolyte cell was postulated, thereby establishing the parameters influencing the effectiveness and efficiency of an in situ O2 production system. The major operating parameters were investigated over a wide range of temperature and pressure. Operating limits imposed by the solid electrolyte material, 8% yttria stabilized zirconia, were determined as a function of the operating temperature.
Interplanetary missions with extraterrestrial returns are limited by large propulsion mass requirements. The injected mass landed on an extraterrestrial body can be reduced substantially by utilizing indigenous materials for the production of propellant on the extraterrestrial body. Analyses reported show that for Mars return missions, in situ production of oxygen during the wait between landing and the next low-energy return opportunity reduces the Earth-launch mass requirements to the allowable limit for direct entry and direct return missions. A small chemical processor using radioisotope thermal energy can extract oxygen several times its own mass from carbon dioxide, during the several-hundred-days wait on Mars. The fundamental element of the concept is the electrolytic process. Solid electrolyte cells for extracting oxygen from gaseous feedstock are identified. The basic physical principles underlying the extraction process are analyzed, and the relations between the major parameters established. The laboratory equipment for experimental investigation of the process is presented.
Thermal Energy Storage Units were developed for storing thermal energy required for operating Vuilleumier cryogenic space coolers. In the course of the development work the thermal characteristics of thermal energy storage material was investigated. By three distinctly different methods it was established that ternary salts did not release fusion energy as determined by ideality at the melting point of the eutectic salt. Phase change energy was released over a relatively wide range of temperature with a large change in volume. This strongly affects the amount of thermal energy that is available to the Vuilleumier cryogenic cooler at its operating temperature range and the amount of thermal energy that can be stored and released during a single storage cycle.
Operational limitations of arc heaters caused by enthalpic stagnation pressures
Reducing the pressure in the vicinity of the arc attachment point by allowing the gas to flow through a supersonic nozzle minimizes local heating rates, prevents ablation, and increases the efficiency of coaxial gas-flow arcs.
High enthalpy constricted arc heater for materials and structural testing
Performance prediction and design analysis of constricted coaxial-flow arc air heaters for materials testing and atmospheric entry simulation
Electronics of plasma arc jet engines
Open-cycle thermodynamics, nozzle fluid dynamics and heat transfer for plasma arc jet engines