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Title: Bellows-Type Accumulators for Liquid Metal Loops of Space Reactor Power Systems

Abstract

In many space nuclear power systems, the primary and/or secondary loops use liquid metal working fluids, and require accumulators to accommodate the change in the liquid metal volume and maintain sufficient subcooling to avoid boiling. This paper developed redundant and light-weight bellows-type accumulators with and without a mechanical spring, and compared the operating condition and mass of the accumulators for different types of liquid metal working fluids and operating temperatures: potassium, NaK-78, sodium and lithium loops of a total capacity of 50 liters and nominal operating temperatures of 840 K, 860 K, 950 K and 1340 K, respectively. The effects of using a mechanical spring and different structural materials on the design, operation and mass of the accumulators are also investigated. The structure materials considered include SS-316, Hastelloy-X, C-103 and Mo-14Re. The accumulator without a mechanical spring weighs 23 kg and 40 kg for a coolant subcooling of 50 K and 100 K, respectively, following a loss of the fill gas. The addition of a mechanical spring comes with a mass penalty, in favor of higher redundancy and maintaining a higher liquid metal subcooling.

Authors:
;  [1];  [2]
  1. Institute for Space and Nuclear Power Studies, University of New Mexico, Albuquerque, NM 87131 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20798014
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: 10.1063/1.2169254; (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; 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; CAPACITY; COOLANTS; DESIGN; HASTELLOY X; LIQUID METAL COOLED REACTORS; LIQUID METALS; LITHIUM; NUCLEAR POWER; POTASSIUM; POTASSIUM ALLOYS; POWER GENERATION; POWER SYSTEMS; REACTOR MATERIALS; SODIUM; SODIUM ALLOYS; SPACE; SPACE VEHICLES; SUBCOOLING; WORKING FLUIDS; NESDPS Office of Nuclear Energy Space and Defense Power Systems

Citation Formats

Tournier, Jean-Michel, El-Genk, Mohamed S., and Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, NM 87131. Bellows-Type Accumulators for Liquid Metal Loops of Space Reactor Power Systems. United States: N. p., 2006. Web. doi:10.1063/1.2169254.
Tournier, Jean-Michel, El-Genk, Mohamed S., & Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, NM 87131. Bellows-Type Accumulators for Liquid Metal Loops of Space Reactor Power Systems. United States. doi:10.1063/1.2169254.
Tournier, Jean-Michel, El-Genk, Mohamed S., and Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, NM 87131. Fri . "Bellows-Type Accumulators for Liquid Metal Loops of Space Reactor Power Systems". United States. doi:10.1063/1.2169254.
@article{osti_20798014,
title = {Bellows-Type Accumulators for Liquid Metal Loops of Space Reactor Power Systems},
author = {Tournier, Jean-Michel and El-Genk, Mohamed S. and Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, NM 87131},
abstractNote = {In many space nuclear power systems, the primary and/or secondary loops use liquid metal working fluids, and require accumulators to accommodate the change in the liquid metal volume and maintain sufficient subcooling to avoid boiling. This paper developed redundant and light-weight bellows-type accumulators with and without a mechanical spring, and compared the operating condition and mass of the accumulators for different types of liquid metal working fluids and operating temperatures: potassium, NaK-78, sodium and lithium loops of a total capacity of 50 liters and nominal operating temperatures of 840 K, 860 K, 950 K and 1340 K, respectively. The effects of using a mechanical spring and different structural materials on the design, operation and mass of the accumulators are also investigated. The structure materials considered include SS-316, Hastelloy-X, C-103 and Mo-14Re. The accumulator without a mechanical spring weighs 23 kg and 40 kg for a coolant subcooling of 50 K and 100 K, respectively, following a loss of the fill gas. The addition of a mechanical spring comes with a mass penalty, in favor of higher redundancy and maintaining a higher liquid metal subcooling.},
doi = {10.1063/1.2169254},
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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