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mkgeo_contraction(1rheolef) rheolef-7.0 mkgeo_contraction(1rheolef)

NAME

mkgeo_contraction -- build an unstructured 2d mesh of an abrupt contraction

SYNOPSIS

  mkgeo_contraction options [nx [ny [nz]]]

EXAMPLE

The following command build a triangle-based 2d unstructured mesh of the [-10,0]x[0,4] u [0,10]x[0,1] mesh 

        mkgeo_contraction > contraction.geo
        geo contraction.geo

DESCRIPTION

This command is convenient for building a mesh for the abrupt contraction, as it is a very classical benchmark in complex fluid flow problems. It calls bamg unstructured mesh generator with anisotropy feature. The mesh files goes on `@var{name'.geo} where name is the basename for the output (see option -name below). The three auxiliary files required for automatic mesh generation with Rheolef combined with bamg are also provided: `@var{name'.bamg}, `@var{name'.bamgcad} and `@var{name'.dmn}.

THE GEOMETRY

The geometry is [-Lu,0]x[0,d] u [0,Ld]x[0,1]. By default c=4 is the contraction ratio and Lu=Ld=10 are the upstream and downstream pipe lengths.
-c float
-Lu float
-Ld float
These options control the geometry parameters.
-cartesian
-zr
-rz
These options control the geometry coordinate system. Default is cartesian. THE DISCRETIZATION: The optional nx and ny arguments are floats that specifies the subdivision in each direction. By default nx=1 and ny=ny. Changing the density applies the factor 1/n to all the mesh edges lengths.
-hmin float
Controls the edge length at the re-entrant corner of the contraction. Default is hmin=0.1. Changing the density by the previous options applies the factor 1/n to hmin also.

BOUNDARY DOMAINS

The boundary sides are represented by domains: axis, wall, upstream and downstream.

OTHERS OPTIONS

-name string
Set the basename for the output files. By default, the basename is contraction.
-split
-nosplit
Split each triangle in three substriangles by inserting the barycenter as an additional node. This is useful for using the Scott and Vogelius incompressible mixed finite element P2-P1d for velocity-pressure approximation. Default is no split.
-clean
-noclean
Clear temporary files (this is the default).
-verbose
-noverbose
In verbose mode, print to stderr all subcommands and logs.

COPYRIGHT

Copyright (C) 2000-2018 Pierre Saramito <Pierre.Saramito@imag.fr> GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
rheolef-7.0 rheolef-7.0