NEBA-3 pin and cermet hybrid bimodal reactor

Early in 1994 a bimodal (power and propulsion) reactor concept that made use of two different fuel types was identified. UN pin fuel was selected for long lifetime to produce electricity, and UO{sub 2}-W cermet was selected for short-time high-temperature propulsion. During the last year the concept has been refined and analyzed as part of the DOE contribution to the joint Air Force Phillips Laboratory-Department of Energy Bimodal Program. With the exception of refractory metal vacuum gaps between the components containing hydrogen propellant and the refractory metal components containing lithium, and high temperature liquid metal-gas heat exchangers, the concept identified as Nuclear Engine for Bimodal Applications (NEBA)-3 uses previously developed and demonstrated technologies, including high efficiency closed Brayton cycle turboalternator-compressors for power production. Using near-term technology NEBA-3 can, as an upper stage to an Atlas IIAS launch vehicle, provide propulsion with specific impulse of about 850 seconds at thrusts of 90 to 925 Newtons, and 10 kilowatts of electricity for ten years. Based on previous cost estimates by DOE and NASA, a minimum program could deliver a flight system such as NEBA-3 within six years at a cost of from $500 to $700 million. The US space reactor power andmore » propulsion community now has the technical capability to deliver such a system early in the next century.« less