A parallel, volumetracking algorithm for unstructured meshes
Abstract
Many diverse areas of industry benefit from the use of volume of fluid methods to predict the movement of materials. Casting is a common method of part fabrication. The accurate prediction of the casting process is pivotal to industry. Mold design and casting is currently considered an art by industry. It typically involves many trial mold designs, and the rejection of defective parts is costly. Failure of cast parts, because residual stresses reduce the part`s strength, can be catastrophic. Cast parts should have precise geometric details that reduce or eliminate the need for machining after casting. Volume of fluid codes will help designers predict how the molten metal fills a mold and where ay trapped voids remain. Prediction of defects due to thermal contraction or expansion will eliminate defective, trial mold designs and speed the parts to market with fewer rejections. Increasing the predictability and therefore the accuracy of the casting process will reduce the art that is involved in mold design and parts casting. Here, recent enhancements to multidimensional volumetracking algorithms are presented. Illustrations in two dimensions are given. The improvements include new, local algorithms for interface normal constructions and a new full remapping algorithm for time integration. Thesemore »
 Authors:
 Los Alamos National Lab., NM (United States)
 Cambridge Power Computing Associates, MA (United States)
 Publication Date:
 Research Org.:
 Los Alamos National Lab., NM (United States)
 Sponsoring Org.:
 USDOE, Washington, DC (United States)
 OSTI Identifier:
 383638
 Report Number(s):
 LAUR962420; CONF96052112
ON: DE96014239; TRN: AHC29621%%84
 DOE Contract Number:
 W7405ENG36
 Resource Type:
 Conference
 Resource Relation:
 Conference: Parallel CFD `96, Capri (Italy), 2023 May 1996; Other Information: PBD: [1996]
 Country of Publication:
 United States
 Language:
 English
 Subject:
 99 MATHEMATICS, COMPUTERS, INFORMATION SCIENCE, MANAGEMENT, LAW, MISCELLANEOUS; 36 MATERIALS SCIENCE; 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; METALS; CASTING; FLUID MECHANICS; ALGORITHMS; FOUNDRIES; COMPUTERAIDED MANUFACTURING; PARALLEL PROCESSING; MESH GENERATION; CASTING MOLDS; FORTRAN; ITERATIVE METHODS
Citation Formats
Mosso, S.J., Swartz, B.K., Kothe, D.B., and Ferrell, R.C. A parallel, volumetracking algorithm for unstructured meshes. United States: N. p., 1996.
Web.
Mosso, S.J., Swartz, B.K., Kothe, D.B., & Ferrell, R.C. A parallel, volumetracking algorithm for unstructured meshes. United States.
Mosso, S.J., Swartz, B.K., Kothe, D.B., and Ferrell, R.C. Tue .
"A parallel, volumetracking algorithm for unstructured meshes". United States.
doi:. https://www.osti.gov/servlets/purl/383638.
@article{osti_383638,
title = {A parallel, volumetracking algorithm for unstructured meshes},
author = {Mosso, S.J. and Swartz, B.K. and Kothe, D.B. and Ferrell, R.C.},
abstractNote = {Many diverse areas of industry benefit from the use of volume of fluid methods to predict the movement of materials. Casting is a common method of part fabrication. The accurate prediction of the casting process is pivotal to industry. Mold design and casting is currently considered an art by industry. It typically involves many trial mold designs, and the rejection of defective parts is costly. Failure of cast parts, because residual stresses reduce the part`s strength, can be catastrophic. Cast parts should have precise geometric details that reduce or eliminate the need for machining after casting. Volume of fluid codes will help designers predict how the molten metal fills a mold and where ay trapped voids remain. Prediction of defects due to thermal contraction or expansion will eliminate defective, trial mold designs and speed the parts to market with fewer rejections. Increasing the predictability and therefore the accuracy of the casting process will reduce the art that is involved in mold design and parts casting. Here, recent enhancements to multidimensional volumetracking algorithms are presented. Illustrations in two dimensions are given. The improvements include new, local algorithms for interface normal constructions and a new full remapping algorithm for time integration. These methods are used on structured and unstructured grids.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Oct 01 00:00:00 EDT 1996},
month = {Tue Oct 01 00:00:00 EDT 1996}
}

We develop a new algorithm for performing parallel S{sub n} sweeps on unstructured meshes. The algorithm uses a lowcomplexity list ordering heuristic to determine a sweep ordering on any partitioned mesh. For typical problems and with ''normal'' mesh partitionings we have observed nearly linear speedups on up to 126 processors. This is an important and desirable result, since although analyses of structured meshes indicate that parallel sweeps will not scale with normal partitioning approaches, we do not observe any severe asymptotic degradation in the parallel efficiency with modest ({le}100) levels of parallelism. This work is a fundamental step in themore »

AN ALGORITHM FOR PARALLEL SN SWEEPS ON UNSTRUCTURED MESHES
We develop a new algorithm for performing parallel S{sub n} sweeps on unstructured meshes. The algorithm uses a lowcomplexity list ordering heuristic to determine a sweep ordering on any partitioned mesh. For typical problems and with ''normal'' mesh partitionings we have observed nearly linear speedups on up to 126 processors. This is an important and desirable result, since although analyses of structured meshes indicate that parallel sweeps will not scale with normal partitioning approaches, we do not observe any severe asymptotic degradation in the parallel efficiency with modest ({le} 100) levels of parallelism. This work is a fundamental step inmore » 
A high resolution finite volume method for efficient parallel simulation of casting processes on unstructured meshes
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High resolution finite volume parallel simulations of mould filling and binary alloy solidification on unstructured 3D meshes
The Los Alamos National Laboratory (LANL) is currently developing a new casting simulation tool (known as Telluride) that employs robust, highresolution finite volume algorithms for incompressible fluid flow, volume tracking of interfaces, and solidification physics on threedimensional (3D) unstructured meshes. Their finite volume algorithms are based on colocated cellcentered schemes that are formally second order in time and space. The flow algorithm is a 3D extension of recent work on projection method solutions of the NavierStokes (NS) equations. Their volume tracking algorithm can accurately track topologically complex interfaces by approximating the interface geometry as piecewise planar. Coupled to their fluidmore » 
An Algorithm for Parallel S{sub n} Sweeps on Unstructured Meshes
A new algorithm for performing parallel S{sub n} sweeps on unstructured meshes is developed. The algorithm uses a lowcomplexity list ordering heuristic to determine a sweep ordering on any partitioned mesh. For typical problems and with 'normal' mesh partitionings, nearly linear speedups on up to 126 processors are observed. This is an important and desirable result, since although analyses of structured meshes indicate that parallel sweeps will not scale with normal partitioning approaches, no severe asymptotic degradation in the parallel efficiency is observed with modest ({<=}100) levels of parallelism. This result is a fundamental step in the development of efficientmore »