Improving convergence rates for low pressure material processing calculations

Moen, C D

Title: Improving convergence rates for low pressure material processing calculations

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Abstract

An enhanced solution strategy for the SIMPLER algorithm is presented for low pressure heat and mass transport calculations with applications in material processing. The accurate solution of highly diffusive flows requires an inflow boundary condition that preserves chemical species mass fluxes. The flux-preserving inflow boundary condition contains a scaling problem that causes the species equations to converge very slowly when using the standard SIMPLER algorithm. A gradient algorithm, coupled to a line-relaxation method, accelerates the convergence of the linear problem. Reformulation of the pressure-correction boundary conditions ensures that continuity is preserved in each finite volume at each iteration. The boundary condition scaling problem is demonstrated with a simple linear model problem. The enhanced solution strategy is implemented in a baseline computer code that is used to solve the multicomponent Navier-Stokes equations on a generalized, multiple-block grid system. Convergence rate acceleration factors of up to 100 are demonstrated for several material processing example problems.

Authors:: Moen, C D

Publication Date:: Sun Dec 01 00:00:00 EST 1996

Research Org.:: Sandia National Lab. (SNL-CA), Livermore, CA (United States)

Sponsoring Org.:: USDOE Office of Energy Research, Washington, DC (United States)

OSTI Identifier:: 453906

Report Number(s):: SAND-96-8559C; CONF-960738-9
ON: DE97050448

DOE Contract Number:: AC04-94AL85000

Resource Type:: Conference

Resource Relation:: Conference: 1996 American Society of Mechanical Engineers (ASME) Fluid Engineering Division summer meeting, San Diego, CA (United States), 7-11 Jul 1996; Other Information: PBD: [1996]

Country of Publication:: United States

Language:: English

Subject:: 99 MATHEMATICS, COMPUTERS, INFORMATION SCIENCE, MANAGEMENT, LAW, MISCELLANEOUS; 36 MATERIALS SCIENCE; HEAT TRANSFER; ALGORITHMS; MASS TRANSFER; MANUFACTURING; COMPUTERIZED SIMULATION; MATERIALS; SCALING; DIFFUSION; CONVECTION; S CODES; BOUNDARY CONDITIONS; PROCESS CONTROL; CALCULATION METHODS; NAVIER-STOKES EQUATIONS; NUMERICAL ANALYSIS

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                    Moen, C D. Improving convergence rates for low pressure material processing calculations.  United States: N. p., 1996. 
        Web.

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                    Moen, C D. Improving convergence rates for low pressure material processing calculations.  United States.

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                    Moen, C D. 1996.  
        "Improving convergence rates for low pressure material processing calculations".  United States.  https://www.osti.gov/servlets/purl/453906.

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@article{osti_453906,

  title        = {Improving convergence rates for low pressure material processing calculations},

  author       = {Moen, C D},

  abstractNote = {An enhanced solution strategy for the SIMPLER algorithm is presented for low pressure heat and mass transport calculations with applications in material processing. The accurate solution of highly diffusive flows requires an inflow boundary condition that preserves chemical species mass fluxes. The flux-preserving inflow boundary condition contains a scaling problem that causes the species equations to converge very slowly when using the standard SIMPLER algorithm. A gradient algorithm, coupled to a line-relaxation method, accelerates the convergence of the linear problem. Reformulation of the pressure-correction boundary conditions ensures that continuity is preserved in each finite volume at each iteration. The boundary condition scaling problem is demonstrated with a simple linear model problem. The enhanced solution strategy is implemented in a baseline computer code that is used to solve the multicomponent Navier-Stokes equations on a generalized, multiple-block grid system. Convergence rate acceleration factors of up to 100 are demonstrated for several material processing example problems.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/453906},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Sun Dec 01 00:00:00 EST 1996},

  month        = {Sun Dec 01 00:00:00 EST 1996}

}

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