Controlling FEA Output

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If FEA files, the Output command defines which results are written to the output text file. Some of the output options can be restricted to selected nodes.

Scripted Input Files

The Output command is used to determine what FEA calculation results are in the output file. The format is

Output #1,#2,<#3,#4>,<#5,#6>,...

where the arguments are given in pairs: (#1,#2), (#3,#4), etc.; the first number gives a calculation result. The options are:

  1. "displacements" to output nodal displacements.
  2. "forces" to output nodal forces calculated in each element.
  3. "elementstresses" to output all components of stress calculated in each element and surface tractions in each <a href="imperfect.html">interface</a> elements.
  4. "nodalstresses" to output average stresses at the nodal points.
  5. "reactivities" to output reaction forces at all nodes with fixed boundary conditions.
  6. "energy" to output strain energy of each element and the total strain energy.

Each output option is followed by an option that determines what is included in the option file. These options are:

  • "yes" means fully output the preceding option. Fully option means to output all nodal results are all element results.
  • "no" means to completely omit the preceding option.
  • "selected" means to only output result relevant to selected nodes, which are selected as described below. If no nodes are selected, this mode will result in no output for that option.

Selecting Nodes

You can select nodes for any output option using the "selected" style with the following commands:

SelectLine command
The SelectLine command is used to select all nodes near a line and it is available in two version:
SelectLine #1,#2,#3,#4,<#5>
or
SelectLine #6
where
  • (#1, #2) and (#3, #4) define (x, y) coordinates (in mm) for the points at the beginning and end of the line (or (R, Z) coordinates if axisymmetric).
  • #5 is optional tolerance (in mm).
  • #6 is the id of a previously defined path.
SelectPoint command
The SelectPoint command is used to select a single node and it is available in two version:
SelectPoint #1,#2
or
SelectPoint #3
where
  • (#1, #2) define (x, y) coordinates (in mm) for a point (or (R, Z) coordinates if axisymmetric). The node closest to that point will be selected.
  • #3 is a previously defined key point. The node at that key point will be selected.
Select command
The Select command (with no arguments can be used within a FixLine Command or a FixPoint Command to select all nodes on the defined line or the single node on the point.

XML Input Files

The Output and Select commands are used to determine what FEA calculation results are in the output file. The format within the main header is:

<Output>YYYYNY</Output>
<Select node='1'/>
<Select node='23'>

The text of the Output command has 1 to 6 letters, each of which must be 'Y', 'C', or 'N' &emdash; 'Y' means that result is fully included in the file; 'C' means that result is conditionally included only if it is relevant to one of a set of preselected nodes; and 'N' means that result is not included in the file. The six output options are listed above. To preselect nodes for the 'C' option, include one or mode Select commands in the main header using its node attribute to specify the node by number.