.TH "mkgeo_obstacle" 1rheolef "Sat Mar 13 2021" "Version 7.1" "rheolef" \" -*- nroff -*-
.ad l
.nh
.SH NAME
mkgeo_obstacle \- mesh of the obstacle-in-channel (rheolef-7\&.1)
.PP
    
.SH "SYNOPSIS"
mkgeo_obstacle [options] [nx [ny]]
.SH "EXAMPLE"
The following command build a triangle-based 2d unstructured mesh of the [-L,L]x[0,c] with a unit circle hole at origin\&. 
.PP
.nf
    mkgeo_obstacle > obstacle.geo
    geo obstacle.geo

.fi
.PP
 
.SH "DESCRIPTION"
This command is convenient for building a mesh for the obstacle-in-channel geometry, as it is a very classical benchmark in complex fluid flow problems\&. It calls \fCbamg\fP unstructured mesh generator with anisotropy feature\&. The mesh files goes on name\&.geo where \fIname\fP is the basename for the output (see option \fC-name\fP below)\&. The three auxiliary files required for automatic mesh generation with Rheolef combined with \fCbamg\fP are also provided: 
.PP
.nf
        name.bamg
        name.bamgcad
        name.dmn

.fi
.PP
 
.SH "THE GEOMETRY"
\fC-c\fP \fIfloat\fP 
.br
\fC-L\fP \fIfloat\fP 
.PP
.RS 4
These options control the geometry parameters\&. Default is c=2 and L=2*c\&. 
.RE
.PP
\fC-cartesian\fP 
.br
\fC-zr\fP 
.PP
.RS 4
These options control the geometry coordinate system\&. Default is Cartesian\&. 
.RE
.PP
\fC-quarter\fP 
.br
\fC-half\fP 
.PP
.RS 4
When the \fCquarter\fP option is activated, the upstream-downstream symmetry is assumed and only one quarter of the geometry is considered\&. Otherwise, with the \fChalf\fP option, the upstream-downstream geometry is generated Default is the \fCquarter\fP option\&. 
.RE
.PP
\fC-N\fP \fIint\fP 
.PP
.RS 4
The number of elements around the half of the circular obstacle\&. When the \fCquarter\fP option is activated, only a quarter 
.br
 of the circular obstacle is considered\&. Default is \fCN=100\fP\&. 
.RE
.PP
.SH "THE DISCRETIZATION"
\fC-hmin\fP \fIfloat\fP 
.PP
.RS 4
Controls the edge length on the obstacle\&. Default is \fChmin\fP=0\&.1\&. Changing the density by the previous options applies the factor 1/n to \fChmin\fP also\&. 
.RE
.PP
.SH "BOUNDARY DOMAINS"
The boundary sides are represented by domains: \fCobstacle\fP, \fCaxis\fP, \fCwall\fP, \fCupstream\fP and \fCdownstream\fP\&.
.SH "OTHERS OPTIONS"
\fC-name\fP \fIstring\fP 
.PP
.RS 4
Set the basename for the output files\&. By default, the basename is \fCobstacle\fP\&. 
.RE
.PP
\fC-[no]split\fP 
.PP
.RS 4
Split each triangle in three subtriangles 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\&. 
.RE
.PP
\fC-[no]clean\fP 
.PP
.RS 4
Clear temporary files (this is the default)\&. 
.RE
.PP
\fC-[no]verbose\fP 
.PP
.RS 4
In verbose mode, print to stderr all commands and logs\&. 
.RE
.PP
.SH "IMPLEMENTATION"
This documentation has been generated from file main/sbin/mkgeo_obstacle\&.sh 
.SH AUTHOR
Pierre  Saramito  <Pierre.Saramito@imag.fr>
.SH 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.