PointList Block

A <PointList> block can explicitly list individual material points. This block is almost never used because it is much better to use [MPM Region and Hole Commands|Region and Hole commands]]. The one exception is when running a calculation based on material point locations from a previous simulation.

PointList Block

An XML file can include one <PointList> block and it must be within the single<MaterialPoints>.

<PointList>
  <mp elem='(elemNum)' mat='(natNum)' angle='(angle)' thick='(thick)' conc='(conc)' temp='(temp)'>
    <pt units='mm' x='1.25' y='-11.25'/>
    <vel units='mm/sec' x='0' y='0'/>
    <mass units='g' m='1e-3'/>
  </mp>
   . . .
</PointList>

Within the <PointList> block,the material points are defined by a series of subordinate <mp> elements. Its attributes are:

• (elemNum) - the element number that contains the material point (this attribute is optional; if not provided the element will be looked up)
• (matNum) - the material nuimber (a number can be replaced by a material name using a matname attribute as explained here.
• (angle) - the material angle (in degrees) which is used for some anisotropic materials (default = 0).
• (thick) - the thickness (in mm), for planar 2D only (default is equal to the grid thickness).
• (conc) - the initial concentration (set as potential from 0 to 1 where 1 is the saturation concentration for the particle's material type) when doing diffusion calculations. Alternatively you can set initial concentration as weight fraction by using a wtconc attribute instead. The weight fraction concentration must be between 0 and the saturation concentration for the particle's material type. If both conc and conc are used, the one that appears last will determine the concentration (default 0).
• (temp) - the initial temperature (temp) when doing thermal loading or conduction calculations (default is the stress free temperature).

Subordinate to each <mp> element, you define the material point properties using <pt> (required), <vel>, and <mass> commands:

• <pt>- gives the x, y, and z (if 3D)) coordinates in attributes in mm, but an optional units attribute can specify other length units (required).
• <vel> - give the material point's initial velocity in the x, y, and z (if 3D) directions in mm/sec. An optional units attribute can specify other velocity units) (default is zero velocity)
• <mass> - normally the particle mass is determined from the size of the elements and the number of particles per element and this command is not used. When running a simulation based on material points from a previous simulation, this command can be used to set the particle mass (in g, but an optional units attribute can specify the mass units).