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Title: Planetary surface reactor shielding using indigenous materials

Abstract

The exploration and development of Mars will require abundant surface power. Nuclear reactors are a low-cost, low-mass means of providing that power. A significant fraction of the nuclear power system mass is radiation shielding necessary for protecting humans and/or equipment from radiation emitted by the reactor. For planetary surface missions, it may be desirable to provide some or all of the required shielding from indigenous materials. This paper examines shielding options that utilize either purely indigenous materials or a combination of indigenous and nonindigenous materials. {copyright} {ital 1999 American Institute of Physics.}

Authors:
; ;  [1];  [2]
  1. Nuclear Systems Design and Analysis Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
  2. Nuclear Technology and Research, Sandia National Laboratories, Albuquerque, New Mexico 87185-1146 (United States)
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
700898
Report Number(s):
CONF-990103-
Journal ID: APCPCS; ISSN 0094-243X; TRN: 9911M0032
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 458; Journal Issue: 1; Conference: 1999 space technology and applications international forum, Albuquerque, NM (United States), 31 Jan - 4 Feb 1999; Other Information: PBD: Jan 1999
Country of Publication:
United States
Language:
English
Subject:
21 NUCLEAR POWER REACTORS AND ASSOCIATED PLANTS; NUCLEAR POWER PLANTS; SHIELDING; MATERIALS; POWER REACTORS; RADIATION PROTECTION; SHIELDING MATERIALS; MARS PLANET; OVERBURDEN; CARBON DIOXIDE; HEAT FLUX

Citation Formats

Houts, Michael G., Poston, David I., Trellue, Holly R., and Lipinski, Ronald J. Planetary surface reactor shielding using indigenous materials. United States: N. p., 1999. Web. doi:10.1063/1.57545.
Houts, Michael G., Poston, David I., Trellue, Holly R., & Lipinski, Ronald J. Planetary surface reactor shielding using indigenous materials. United States. doi:10.1063/1.57545.
Houts, Michael G., Poston, David I., Trellue, Holly R., and Lipinski, Ronald J. 1999. "Planetary surface reactor shielding using indigenous materials". United States. doi:10.1063/1.57545.
@article{osti_700898,
title = {Planetary surface reactor shielding using indigenous materials},
author = {Houts, Michael G. and Poston, David I. and Trellue, Holly R. and Lipinski, Ronald J.},
abstractNote = {The exploration and development of Mars will require abundant surface power. Nuclear reactors are a low-cost, low-mass means of providing that power. A significant fraction of the nuclear power system mass is radiation shielding necessary for protecting humans and/or equipment from radiation emitted by the reactor. For planetary surface missions, it may be desirable to provide some or all of the required shielding from indigenous materials. This paper examines shielding options that utilize either purely indigenous materials or a combination of indigenous and nonindigenous materials. {copyright} {ital 1999 American Institute of Physics.}},
doi = {10.1063/1.57545},
journal = {AIP Conference Proceedings},
number = 1,
volume = 458,
place = {United States},
year = 1999,
month = 1
}
  • The exploration and development of Mars will require abundant surface power. Nuclear reactors are a low-cost, low-mass means of providing that power. A significant fraction of the nuclear power system mass is radiation shielding necessary for protecting humans and/or equipment from radiation emitted by the reactor. For planetary surface missions, it may be desirable to provide some or all of the required shielding from indigenous materials. This paper examines shielding options that utilize either purely indigenous materials or a combination of indigenous and nonindigenous materials.
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  • A nuclear reactor system could provide power to support long term human exploration of the moon. Such a system would require shielding to protect astronauts from its emitted radiations. Shielding studies have been performed for a Gas Cooled Reactor system because it is considered to be the most suitable nuclear reactor system available for lunar exploration, based on its tolerance of oxidizing lunar regolith and its good conversion efficiency. The goals of the shielding studies were to determine a material shielding configuration that reduces the dose (rem) to the required level in order to protect astronauts, and to estimate themore » mass of regolith that would provide an equivalent protective effect if it were used as the shielding material. All calculations were performed using MCNPX, a Monte Carlo transport code. Lithium hydride must be kept between 600 K and 700 K to prevent excessive swelling from large amounts of gamma or neutron irradiation. The issue is that radiation damage causes separation of the lithium and the hydrogen, resulting in lithium metal and hydrogen gas. The proposed design uses a layer of B4C to reduce the combined neutron and gamma dose to below 0.5Grads before the LiH is introduced. Below 0.5Grads the swelling in LiH is small (less than about 1%) for all temperatures. This approach causes the shield to be heavier than if the B4C were replaced by LiH, but it makes the shield much more robust and reliable.« less