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Title: Radiation Shielding Design and Orientation Considerations for a 1 kWe Heat Pipe Cooled Reactor Utilized to Bore Through the Ice Caps of Mars

Abstract

The goal in designing any space power system is to develop a system able to meet the mission requirements for success while minimizing the overall costs. The mission requirements for the this study was to develop a reactor (with Stirling engine power conversion) and shielding configuration able to fit, along with all the other necessary science equipment, in a Cryobot 3 m high with {approx}0.5 m diameter hull, produce 1 kWe for 5yrs, and not adversely affect the mission science by keeping the total integrated dose to the science equipment below 150 krad. Since in most space power missions the overall system mass dictates the mission cost, the shielding designs in this study incorporated Martian water extracted at the startup site in order to minimize the tungsten and LiH mass loading at launch. Different reliability and mass minimization concerns led to three design configuration evolutions. With the help of implementing Martian water and configuring the reactor as far from the science equipment as possible, the needed tungsten and LiH shield mass was minimized. This study further characterizes the startup dose and the necessary mission requirements in order to ensure integrity of the surface equipment during reactor startup phase.

Authors:
 [1];  [2];  [3];  [4];  [5]
  1. Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, FL 32611 (United States)
  2. (United States)
  3. Jet Propulsion Laboratories, California Institute of Technology, Pasedena, Ca 91109 (United States)
  4. Sandia National Laboratory, Albuquerque, NM 87185 (United States)
  5. Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)
Publication Date:
OSTI Identifier:
20797998
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 813; Journal Issue: 1; Conference: 10. conference on thermophysics applications in microgravity; 23. symposium on space nuclear power and propulsion; 4. conference on human/robotic technology and the national vision for space exploration; 4. symposium on space colonization; 3. symposium on new frontiers and future concepts, Albuquerque, NM (United States), 12-16 Feb 2006; Other Information: DOI: 10.1063/1.2169222; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COST; DESIGN; ENERGY CONVERSION; HEAT PIPES; ICE CAPS; LITHIUM HYDRIDES; MINIMIZATION; POWER GENERATION; POWER SYSTEMS; RADIATION PROTECTION; REACTORS; RELIABILITY; SHIELDING; SHIELDS; SPACE; SPACE VEHICLES; STIRLING ENGINES; TUNGSTEN; NESDPS Office of Nuclear Energy Space and Defense Power Systems

Citation Formats

Fensin, Michael L., Los Alamos National Laboratory, Los Alamos, NM 87545, Elliott, John O., Lipinski, Ronald J., and Poston, David I. Radiation Shielding Design and Orientation Considerations for a 1 kWe Heat Pipe Cooled Reactor Utilized to Bore Through the Ice Caps of Mars. United States: N. p., 2006. Web. doi:10.1063/1.2169222.
Fensin, Michael L., Los Alamos National Laboratory, Los Alamos, NM 87545, Elliott, John O., Lipinski, Ronald J., & Poston, David I. Radiation Shielding Design and Orientation Considerations for a 1 kWe Heat Pipe Cooled Reactor Utilized to Bore Through the Ice Caps of Mars. United States. doi:10.1063/1.2169222.
Fensin, Michael L., Los Alamos National Laboratory, Los Alamos, NM 87545, Elliott, John O., Lipinski, Ronald J., and Poston, David I. Fri . "Radiation Shielding Design and Orientation Considerations for a 1 kWe Heat Pipe Cooled Reactor Utilized to Bore Through the Ice Caps of Mars". United States. doi:10.1063/1.2169222.
@article{osti_20797998,
title = {Radiation Shielding Design and Orientation Considerations for a 1 kWe Heat Pipe Cooled Reactor Utilized to Bore Through the Ice Caps of Mars},
author = {Fensin, Michael L. and Los Alamos National Laboratory, Los Alamos, NM 87545 and Elliott, John O. and Lipinski, Ronald J. and Poston, David I.},
abstractNote = {The goal in designing any space power system is to develop a system able to meet the mission requirements for success while minimizing the overall costs. The mission requirements for the this study was to develop a reactor (with Stirling engine power conversion) and shielding configuration able to fit, along with all the other necessary science equipment, in a Cryobot 3 m high with {approx}0.5 m diameter hull, produce 1 kWe for 5yrs, and not adversely affect the mission science by keeping the total integrated dose to the science equipment below 150 krad. Since in most space power missions the overall system mass dictates the mission cost, the shielding designs in this study incorporated Martian water extracted at the startup site in order to minimize the tungsten and LiH mass loading at launch. Different reliability and mass minimization concerns led to three design configuration evolutions. With the help of implementing Martian water and configuring the reactor as far from the science equipment as possible, the needed tungsten and LiH shield mass was minimized. This study further characterizes the startup dose and the necessary mission requirements in order to ensure integrity of the surface equipment during reactor startup phase.},
doi = {10.1063/1.2169222},
journal = {AIP Conference Proceedings},
number = 1,
volume = 813,
place = {United States},
year = {Fri Jan 20 00:00:00 EST 2006},
month = {Fri Jan 20 00:00:00 EST 2006}
}
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