Analysis of NTR Engines Utilizing Prismatic Fuel Elements Derived from the GE-710 Program

摘要

Nuclear rocket engines utilizing W-UO_2 ceramic-metal (cermet) fuel with a prismatic geometry based on the GE-710 design are analyzed. A highly detailed Monte Carlo N-Particle (MCNP) model of the reactor core is developed and exercised to determine the energy deposited in both the fuel matrix itself and the various engine components via decelerating fission products and scattered neutrons and photons. These results are then used by NASA's Nuclear Engine System Simulation (NESS) code to determine both engine performance characteristics and thermodynamic state points throughout the cycle, and estimate engine mass. The engines are expander cycle based, but do not utilize tie-tubes to extract thermal energy from the reactor to drive the turbo-machinery. Instead, fuel elements located at the periphery of the reactor core are utilized to provide the additional thermal energy required to close the cycle.