Hybrid thermionic space reactor for power and propulsion

Journal Article · Mon Aug 01 00:00:00 EDT 1994 · Nuclear Technology; (United States)

OSTI ID:6936742

Sahin, S ^[1]; Kennel, E B ^[2]

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1. Gazi Univ., Ankara (Turkey). Teknik Egitim Fakueltesi
2. Space Exploration Associates, Cedarville, OH (United States)

A thermo-hydrodynamic-neutronic analysis is performed for a fast, uranium carbide (UC) fueled space-craft nuclear in-core thermionic reactor. The thermo-hydrodynamic analysis shows that a hybrid thermionic spacecraft nuclear reactor can be designed for both electricity generation and nuclear thermal propulsion purposes. The neutronic analysis has been conducted in S[sub 8]-P[sub 3] approximation with the help of one- and two-dimensional neutron transport codes ANISN and DORT, respectively. The calculations have shown that a UC fueled electricity generating single mode thermionic nuclear reactor can be designed to be extremely compact because of the high atomic density of the nuclear fuel (by 95% sintering density), namely, with a core radius of 8.7 cm and core height of 25 cm, leading to power levels as low as 5 kW (electric) by an electrical output on an emitter surface of 1.243 W/cm[sup 2]. A reactor control with boronated reflector drums at the outer periphery of the radial reflector of 16-cm thickness would make possible reactivity changes of [Delta]k[sub eff] > 10% -- amply sufficient for a fast reactor -- without a significant distortion of the fission power profile during all phases of the space mission. The hybrid thermionic spacecraft nuclear reactor mode contains cooling channels in the nuclear fuel for the hydrogen propellant. This increase the critical reactor size because of the lower uranium atomic density in this design concept. Calculations have lead to a reactor with a core radius of 22 cm and core height of 35 cm leading to power levels [approximately] 50 kW(electric) under the aforementioned thermionic conversion conditions.

• OSTI ID: 6936742
• Journal Information: Nuclear Technology; (United States), Vol. 107:2; ISSN 0029-5450
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
30 DIRECT ENERGY CONVERSION
SPACE POWER REACTORS
DESIGN
THERMIONIC REACTORS
HEAT TRANSFER
HYDRAULICS
REACTOR CONTROL SYSTEMS
REACTOR COOLING SYSTEMS
SPACECRAFT POWER SUPPLIES
CONTROL SYSTEMS
COOLING SYSTEMS
ELECTRONIC EQUIPMENT
ENERGY SYSTEMS
ENERGY TRANSFER
EQUIPMENT
FLUID MECHANICS
MECHANICS
MOBILE REACTORS
POWER REACTORS
POWER SUPPLIES
REACTOR COMPONENTS
REACTORS
NESDPS Office of Nuclear Energy Space and Defense Power Systems
210600* - Power Reactors
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& Transportable
300404 - Thermionic Converters- Applications