Physics study of nuclear reactors for space and rocket propulsions

Abstract

With the renewed interest in human exploration of the solar system, new types of space propulsions systems must be studied and developed in order to reduce both the costs as well as the transit times of these missions. One such promising avenue of research is the development of the nuclear thermal rocket, a concept that was extensively explored in the 1960s and 70s by both the US and the former Soviet Union. The purpose of this study is to look at the feasibility of using alternative fuels to the traditional highly enriched uranium fuels used in previous research. This paper will present a study of the traditional NERVA reactor core, and compare the results with previous work done at Idaho National Laboratory (INL). The purpose of this initial study is to create a baseline with which to perform further analysis and to build a solid understanding of the neutronic characteristics of a solid core for the nuclear thermal rocket. Once consistency with work done at INL is established, this paper will provide a study of other fuel types, such as low andmedium-enriched uranium fuels. In this study, the paper will examine how the implementation of each fuel type affectsthe multiplication factor of the reactor, and will then explore different possibilitiesfor alterations needed to accommodatetheir successful usage. The reactor core analysis will be done by usingthe MCNP5Monte Carlo code.