Main Help → All Commands → MPM Grid and Material Points → Intensity
The Intensity
command is used to map levels in a gray-scale BMP File image to different types of material points or to different material initial conditions in an MPM analysis. For FEA calculations, it is used to material the image to different types of materials to assign to mesh elements. When a second mask BMP File is used to determine material angles, another Intensity
command is used to map intensities to an angle. The two forms are:
Intensity (id),(imin),(imax),<(prop),(value)>,...
or
Intensity "angles",(imin),(imax),(angle1),(angle2)
where:
(id)
is the material ID for a previously defined material. When the first argument is "angles"
(or actually any text that is not a material ID), then that command is used to map intensities to material angle in the mask BMP file. Angle mapping for more than one BMP file in 3D simulations can be done by using more than one Intensity
command. Each extra command maps the corresponding BMP in the BMPRegion command in order provided. If there are fewer Intensity
commands then BMP angle files, the remaining files will use the map set by the last Intensity
command(imin)
and (imax)
are the range in gray-scale intensities to map to this material or two intensities corresponding to material angles. The numbers must be from 0 (for black) to 255 (for white) and (imin)
must be less than or equal to (imax)
.(id)
is a material ID, one or more <(prop),(value)
>optional pairs are arguments to specify initial conditions for the particles in the intensity range, ehere (prop)
defines the property and (value)
defines the value. The properties for both FEA and MPM are:
"thick"
for particle or element thickness in planar 2D calculations in length units."angle"
for angle for the material which is only relevant for anisotropic materials. The units are degrees. This angle is constant rotation angle about z axis. Use Rotate command to handle non-constant rotations or rotations about other axes."temp"
for particle temperature. The units are degrees."vx"
for particle x-direction velocity (R direction is axisymmetric) in velocity unitsc."vy"
for particle y-direction velocity (Z direction is axisymmetric) in velocity units."vz"
for particle z-direction velocity in 3D MPM in velocity units."conc"
for particle concentration."pp"
for particle pore pressure in pressure units."angles"
(or any non-material ID), (angle1)
and (angle2)
determine the angles (in degrees) corresponding to the intensity values in (imin)
and (imax)
in the mask BMP file. The angle will be calculated by a linear interpolation between (imin,angle1)
and (imax,angle2)
. If more than one (anglepath)
file is usedin the BMPRegion command, you can have a corresponding number of Intensity
commands to set angle mapping for each file. If fewer Intensity
comands are used then (anglepath)
files, the extra files will use the mapping of the last Intensity command.Intensity
commands in a single BMPRegion block
can be used to define a composite material or to define regions with different initial conditions.Intensity
command range, will be left empty in the grid or mesh.