Nuclear heating in He-3 fast SCRAM rods

Baumann, N P; Flach, G P

doi:10.2172/6975970

Title: Nuclear heating in He-3 fast SCRAM rods

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Abstract

Nuclear heating occurs in the He-3 fill gas of the fast SCRAM rods as a result of the very neutron captures which make the rods operative. This heating gives rise to a pressure rise within the rod. If severe enough this heating could present a structural problem, but more importantly the pressurization always causes a partial backflow of the fill gas. This, in turn, reduces the residual gas content and thus reduces the effectiveness of the rod. If enough gas were expelled, the rod would no longer have the required reactivity shutdown margin. This memorandum discusses the bases for determining the heat input and estimating the resultant temperatures, pressures, and backflows to be expected under various assumed design and operational conditions. A method for mitigating the effect by means of heat-conducting fins on the interior surface of the rods is discussed and evaluated. 5 refs.

Authors:: Baumann, N P; Flach, G P

Publication Date:: Fri Sep 01 00:00:00 EDT 1989

Research Org.:: Savannah River Site (SRS), Aiken, SC (United States)

Sponsoring Org.:: DOE/DP

OSTI Identifier:: 6975970

Report Number(s):: WSRC-RP-89-770
ON: DE90009302

DOE Contract Number:: AC09-89SR18035

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 22 GENERAL STUDIES OF NUCLEAR REACTORS; 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; HEATING; COMPUTERIZED SIMULATION; PRODUCTION REACTORS; SCRAM RODS; B CODES; COMPARATIVE EVALUATIONS; DESIGN; EQUILIBRIUM; FUEL ASSEMBLIES; G CODES; H CODES; HEAT TRANSFER; MODIFICATIONS; NEUTRONS; NUSSELT NUMBER; PRESSURE EFFECTS; REACTOR CONTROL SYSTEMS; REACTOR OPERATION; SAVANNAH RIVER PLANT; STRUCTURAL MODELS; TEMPERATURE EFFECTS; THERMODYNAMICS; TRANSIENTS; BARYONS; COMPUTER CODES; CONTROL ELEMENTS; CONTROL SYSTEMS; ELEMENTARY PARTICLES; ENERGY TRANSFER; FERMIONS; HADRONS; NATIONAL ORGANIZATIONS; NUCLEONS; OPERATION; REACTOR COMPONENTS; REACTORS; SIMULATION; US AEC; US DOE; US ERDA; US ORGANIZATIONS; 220900* - Nuclear Reactor Technology- Reactor Safety; 220700 - Nuclear Reactor Technology- Plutonium & Isotope Production Reactors

Citation Formats


                    Baumann, N P, and Flach, G P. Nuclear heating in He-3 fast SCRAM rods.  United States: N. p., 1989. 
        Web.  doi:10.2172/6975970.

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                    Baumann, N P, & Flach, G P. Nuclear heating in He-3 fast SCRAM rods.  United States.  https://doi.org/10.2172/6975970

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                    Baumann, N P, and Flach, G P. 1989.  
        "Nuclear heating in He-3 fast SCRAM rods".  United States.  https://doi.org/10.2172/6975970.  https://www.osti.gov/servlets/purl/6975970.

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@article{osti_6975970,

  title        = {Nuclear heating in He-3 fast SCRAM rods},

  author       = {Baumann, N P and Flach, G P},

  abstractNote = {Nuclear heating occurs in the He-3 fill gas of the fast SCRAM rods as a result of the very neutron captures which make the rods operative. This heating gives rise to a pressure rise within the rod. If severe enough this heating could present a structural problem, but more importantly the pressurization always causes a partial backflow of the fill gas. This, in turn, reduces the residual gas content and thus reduces the effectiveness of the rod. If enough gas were expelled, the rod would no longer have the required reactivity shutdown margin. This memorandum discusses the bases for determining the heat input and estimating the resultant temperatures, pressures, and backflows to be expected under various assumed design and operational conditions. A method for mitigating the effect by means of heat-conducting fins on the interior surface of the rods is discussed and evaluated. 5 refs.},

  doi          = {10.2172/6975970},

  url          = {https://www.osti.gov/biblio/6975970},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Fri Sep 01 00:00:00 EDT 1989},

  month        = {Fri Sep 01 00:00:00 EDT 1989}

}

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