PointList Block

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A <PointList> block can explicitly list individual material points.

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'/>
  </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.
  • (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.
  • (temp) - the initial temperature (temp) when doing thermal loading or conduction calculations.

The elements subordinate to <mp> define the material point location (<pt> and its (x, y, (z if 3D)) coordinates in attributes in mm, but an optional units attribute can specify other length units) and the material point's initial velocity (<vel> and the velocity in the x, y, and z (if 3D) directions in mm/sec, but an optional units attribute can specify other velocity units). If not specified, the initial velocity, angle, and concentration potential will all be zero, the thickness (if planar 2D) will be the grid thickness, and the temperature will be equal to the stress-free temperature. For axisymmetric calculations use x and y to enter R and Z coordinates.

Normally the particle mass is determined from the size of the elements and the number of particles per element. When running a simulation based on material points from a previous simulation, a subordinate <mass> element can be used to set the particle mass (in g, but an optional units attribute can specify the mass units).