PointList Block

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A <PointList> block can explicitly list individual material points. This block is almost never used because it is much better to use 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>.

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

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 length units), 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 length units and this element is required (if using Legacy units where coordinates units are in mm, an optional units attribute can specify other length units).
  • <vel> - give the material point's initial velocity in the x, y, and z (if 3D) directions in velocity units (if using Legacy units where velocity units are in mm/s, an optional units attribute can specify other velocity units). If omitted, velocity is set to zero.
  • <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 mass units (if using Legacy units where mass units are in g, an optional units attribute can specify other mass units).