Hexahedron, wedge, tetrahedron, and pyramid diffusion operator discretization

Roberts, R M

doi:10.2172/442193

Title: Hexahedron, wedge, tetrahedron, and pyramid diffusion operator discretization

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Abstract

The diffusion equation, {phi}({rvec x}), is solved by finding the extrema of the functional, {Gamma}[{phi}] = {integral}({1/2}D{rvec {nabla}}{phi}{center_dot}{rvec {nabla}}{phi} + {1/2}{sigma}{sub a}{phi}{sup 2} - {ital Q}{phi}){ital d}{sup 3}{ital x}. A matrix is derived that is investigated for hexahedron, wedge, tetrahedron, and pyramid cells. The first term of the diffusion integration was concentrated and the others dropped; these dropped terms are also considered. Results are presented for hexahedral meshes and three weighting methods.

Authors:: Roberts, R M

Publication Date:: Tue Aug 06 00:00:00 EDT 1996

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE, Washington, DC (United States)

OSTI Identifier:: 442193

Report Number(s):: LA-UR-96-3501
ON: DE97001352

DOE Contract Number:: W-7405-ENG-36

Resource Type:: Technical Report

Resource Relation:: Other Information: PBD: 6 Aug 1996

Country of Publication:: United States

Language:: English

Subject:: 66 PHYSICS; 99 MATHEMATICS, COMPUTERS, INFORMATION SCIENCE, MANAGEMENT, LAW, MISCELLANEOUS; DIFFUSION; MATHEMATICAL MODELS; INTEGRAL EQUATIONS; GEOMETRY; MESH GENERATION; MATRICES; WEIGHTING FUNCTIONS

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                    Roberts, R M. Hexahedron, wedge, tetrahedron, and pyramid diffusion operator discretization.  United States: N. p., 1996. 
        Web.  doi:10.2172/442193.

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                    Roberts, R M. Hexahedron, wedge, tetrahedron, and pyramid diffusion operator discretization.  United States.  https://doi.org/10.2172/442193

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                    Roberts, R M. 1996.  
        "Hexahedron, wedge, tetrahedron, and pyramid diffusion operator discretization".  United States.  https://doi.org/10.2172/442193.  https://www.osti.gov/servlets/purl/442193.

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@article{osti_442193,

  title        = {Hexahedron, wedge, tetrahedron, and pyramid diffusion operator discretization},

  author       = {Roberts, R M},

  abstractNote = {The diffusion equation, {phi}({rvec x}), is solved by finding the extrema of the functional, {Gamma}[{phi}] = {integral}({1/2}D{rvec {nabla}}{phi}{center_dot}{rvec {nabla}}{phi} + {1/2}{sigma}{sub a}{phi}{sup 2} - {ital Q}{phi}){ital d}{sup 3}{ital x}. A matrix is derived that is investigated for hexahedron, wedge, tetrahedron, and pyramid cells. The first term of the diffusion integration was concentrated and the others dropped; these dropped terms are also considered. Results are presented for hexahedral meshes and three weighting methods.},

  doi          = {10.2172/442193},

  url          = {https://www.osti.gov/biblio/442193},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Aug 06 00:00:00 EDT 1996},

  month        = {Tue Aug 06 00:00:00 EDT 1996}

}

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