Parametric Analyses of a 75 kN Thrust Class Composite Fuel Based NTR Engine

Abstract

Numerous recent architecture studies have indicated that a Nuclear Thermal Rocket (NTR) engine in the 75 kN (16.9 klbf) thrust class is a good candidate for various cargo and unmanned probe missions. In order to parametrically evaluate this thrust class of engine, a highly detailed Monte Carlo N-Particle (MCNP) model of the Small Nuclear Rocket Engine (SNRE) is developed and exercised to determine the thermal energy deposition rate in the various engine components. These results are then used by the Nuclear Engine System Simulation (NESS) code to model an expander cycle based NTR engine based on the SNRE design, and a perform parametric sweep in chamber pressure for two different tubopump assembly (TPA) models to evaluate their effect on engine system level performance parameters. Additional analysis is then conducted to determine the applicability of RL60 turbo machinery to this thrust class of NTR engine.