NAME

       mkgeo_ugrid - unstructured mesh of a parallelepiped (rheolef-7.1)

SYNOPSIS

       mkgeo_ugrid [options] n

EXAMPLE

           mkgeo_ugrid -t 10 > square-10.geo
           geo square-10.geo

        The previous command build a triangle based 2d unstructured mesh of the unit square:

DESCRIPTION

       This command is useful when testing programs on simple geometries. Invocation is similar to those of
       mkgeo_grid(1) . It callsg gmsh as unstructured mesh generator. It avoid the preparation of an input file
       for a mesh generator. The optional n argument is an integer that specifies the subdivision in each
       direction. By default n=10. The mesh files goes on standard output.

       The command supports all the possible element types: edges, triangles, rectangles, tetrahedra, prisms and
       hexahedra. It supports also mixed 2D with triangles and quadrangles:

           mkgeo_ugrid -tq 10 | geo -

        and mixed 3D with tetraedra, prisms and/or hexahedra:

           mkgeo_ugrid -TP  10 | geo -paraview -
           mkgeo_ugrid -PH  10 | geo -paraview -
           mkgeo_ugrid -TPH 10 | geo -paraview -

ELEMENT TYPE OPTION

       -e

           1d mesh using edges.

       -t

           2d mesh using triangles.

       -q

           2d mesh using quadrangles (rectangles).

       -T

           3d mesh using tetrahedra.

       -P

           3d mesh using prisms.

       -H

           3d mesh using hexahedra.

       -tq

           2d mesh using both triangles and quadrangles.

       -TP
       -PH
       -TPH

           3d mixed mesh combining tetrahedra, prisms and/or hexahedra.

THE GEOMETRY

       -a float
       -b float
       -c float
       -d float
       -f float
       -g float

           The geometry can be any [a,b] segment, [a,b]x[c,d] rectangle or [a,b]x[c,d]x[f,g] parallelepiped. By
           default a=c=f=0 and b=d=g=1, thus, the unit boxes are considered.

BOUNDARY DOMAINS

       -[no]sides

           The boundary sides are represented by domains: left, right, top, bottom, front and back.

       -[no]boundary

           This option defines a domain named boundary that groups all sides.

REGIONS

       -[no]region

           The whole domain is split into two subdomains: east and west. Also, the separating domain is named
           interface in the mesh. This option is used for testing computations with subdomains (e.g.
           transmission problem; see usersguide ).

CORNERS

       -[no]corner

           The corners (four in 2D and eight in 3D) are defined as OD-domains. This could be useful for some
           special boundary conditions.

COORDINATE SYSTEM OPTIONS

       -cartesian
       -rz
       -zr

           Specifies the coordinate system. The default is cartesian while -rz and -zr denotes some axisymmetric
           coordinate systems. Recall that most of Rheolef codes are coordinate-system independent and the
           coordinate system is specified in the geometry file .geo.

THE MESH ORDER

       This option is related to curved boundaries. Since boundaries are here flat, this option has no practical
       effect and is provided for test purpose only.

       -order int

           The polynomial approximation mesh order, as defined by gmsh. This option enable a possible curved
           boundary, when applying a suitable nonlinear transformation to the mesh. Default is order=1.

IMPLEMENTATION

       This documentation has been generated from file main/sbin/mkgeo_ugrid.sh

AUTHOR

       Pierre  Saramito  <Pierre.Saramito@imag.fr>

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.