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NASA NTRS · 20220001928

Nuclear Electric Propulsion Modular Power Conversion Model

Abstract

This work builds upon a previously examined single loop power conversion cycle for nuclear electric propulsion systems. The intent of this model is to enable examination of trends within the system and extract system parameters that could be used in a mass model to understand how technology performance may impact overall system mass.Several model upgrades were made since the previous work which included physics-based sizing of the turbomachinery and pressure loss inside the radiator. A higher fidelity and modular fluid property code was also developed to help understand the impact of variable fluid properties more accurately and allow for the analysis of different fluids in the same model. The upgraded model features radiator and reactor loops with separate fluids from the Brayton cycle to understand advantages and disadvantages of using multiple working fluids as well as the capability of simulating off nominal system performance. The latter provides a steppingstone for modeling the transient performance of the power conversion system.

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BibTeXRIS

Dennis Nikitaev, Corey D. Smith, Matthew Duchek, Christopher Harnack, William Machemer, Emanuel Grella. Nuclear Electric Propulsion Modular Power Conversion Model. https://ntrs.nasa.gov/citations/20220001928

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