Two-dimensional finite element multigroup diffusion theory for neutral atom transport in plasmas

Hasan, M Z; Conn, R W

doi:10.2172/5841629

Title: Two-dimensional finite element multigroup diffusion theory for neutral atom transport in plasmas

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Abstract

Solution of the energy dependent diffusion equation in two dimensions is formulated by multigroup approximation of the energy variable and general triangular mesh, finite element discretization of the spatial domain. Finite element formulation is done by Galerkin's method. Based on this formulation, a two-dimensional multigroup finite element diffusion theory code, FENAT, has been developed for the transport of neutral atoms in fusion plasmas. FENAT solves the multigroup diffusion equation in X-Y cartesian and R-Z cylindrical/toroidal geometries. Use of the finite element method allows solution of problems in which the plasma cross-section has an arbitrary shape. The accuracy of FENAT has been verified by comparing results to those obtained using the two-dimensional discrete ordinate transport theory code, DOT-4.3. Results of application of FENAT to the transport of limiter-originated neutral atoms in a tokamak fusion machine are presented.

Authors:: Hasan, M Z; Conn, R W

Publication Date:: Sat Feb 01 00:00:00 EST 1986

Research Org.:: California Univ., Los Angeles (USA). Dept. of Mechanical, Aerospace and Nuclear Engineering

OSTI Identifier:: 5841629

Report Number(s):: UCLA/PPG-916
ON: DE86011441

DOE Contract Number:: FG03-86ER52130

Resource Type:: Technical Report

Resource Relation:: Other Information: Portions of this document are illegible in microfiche products. Original copy available until stock is exhausted

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; PLASMA; TRANSPORT THEORY; TOKAMAK DEVICES; ATOMS; COMPUTER CALCULATIONS; DIFFUSION; FINITE ELEMENT METHOD; TWO-DIMENSIONAL CALCULATIONS; CLOSED PLASMA DEVICES; NUMERICAL SOLUTION; THERMONUCLEAR DEVICES; 700105* - Fusion Energy- Plasma Research- Plasma Kinetics-Theoretical- (-1987)

Citation Formats


                    Hasan, M Z, and Conn, R W. Two-dimensional finite element multigroup diffusion theory for neutral atom transport in plasmas.  United States: N. p., 1986. 
        Web.  doi:10.2172/5841629.

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                    Hasan, M Z, & Conn, R W. Two-dimensional finite element multigroup diffusion theory for neutral atom transport in plasmas.  United States.  https://doi.org/10.2172/5841629

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                    Hasan, M Z, and Conn, R W. 1986.  
        "Two-dimensional finite element multigroup diffusion theory for neutral atom transport in plasmas".  United States.  https://doi.org/10.2172/5841629.  https://www.osti.gov/servlets/purl/5841629.

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@article{osti_5841629,

  title        = {Two-dimensional finite element multigroup diffusion theory for neutral atom transport in plasmas},

  author       = {Hasan, M Z and Conn, R W},

  abstractNote = {Solution of the energy dependent diffusion equation in two dimensions is formulated by multigroup approximation of the energy variable and general triangular mesh, finite element discretization of the spatial domain. Finite element formulation is done by Galerkin's method. Based on this formulation, a two-dimensional multigroup finite element diffusion theory code, FENAT, has been developed for the transport of neutral atoms in fusion plasmas. FENAT solves the multigroup diffusion equation in X-Y cartesian and R-Z cylindrical/toroidal geometries. Use of the finite element method allows solution of problems in which the plasma cross-section has an arbitrary shape. The accuracy of FENAT has been verified by comparing results to those obtained using the two-dimensional discrete ordinate transport theory code, DOT-4.3. Results of application of FENAT to the transport of limiter-originated neutral atoms in a tokamak fusion machine are presented.},

  doi          = {10.2172/5841629},

  url          = {https://www.osti.gov/biblio/5841629},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Sat Feb 01 00:00:00 EST 1986},

  month        = {Sat Feb 01 00:00:00 EST 1986}

}

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