Seeded Hydrogen in Mars Transfer Vehicles Using Nuclear Thermal Propulsion Engines

Abstract

Using the NASA Design Reference Architecture, an Aerojet Rocketdyne vehicle architecture, and a University of Alabama in Huntsville nuclear thermal propulsion engine model, the performance of a Mars transfer vehicle using hydrogen propellant seeded with argon was analyzed. Seeded hydrogen, up to a maximum seed mass concentration of 55.85%, increased engine and vehicle performance by reducing pressure losses, decreasing reactor power, and increasing the overall while assuming constant propellant volume and vehicle dry mass. The tradeoff for using seeded hydrogen was lowered specific impulse and increased net propellant mass, resulting in increased vehicle wetted mass. Vehicle performance monotonically increased with seed mass concentration and provided a best-case 32-day reduction in round-trip transit time to Mars versus pure hydrogen.