Grid BC Shape Commands

These commands define shapes. All nodes contained with in the shape will be assigned boundary conditions specified within the shape command.

Line (2D and Axisymmetric)

The command to select a line through a 2D mesh in scripted files is:

MoveLine (x1),(y1),(x2),(y2),(tolerance)
  (one or more velocity, temperature, or concentration condition)
    ...
EndMoveLine

In XML files, a line is selected with:

<BCLine units='(units)' x1='(x1)' y1='(y1)' x2='(x2)' y2='(y2)' tolerance='(tolerance)'>
  (one or more velocity, temperature, or concentration condition)
    ...
</BCLine>

where

• (x1, y1) to (x2, y2) define (x, y) coordinates for the points at the beginning and end of the line (or (R, Z) coordinates if axisymmetric). The units are mm (or determined by a units attribute in XML files).
• (tolerance) is an optional tolerance. If it is omitted, the tolerance will be set to a small fraction of the grid's cell minimum cell size.

This command will apply velocity, temperature, and/or concentration boundary conditions to all nodes with (tolerance) of the line from (x1, y1) to (x2, y2).

Arc (2D or Axisymmetric)

The command to select an arc through a 2D mesh in scripted files is:

MoveArc (x1),(y1),(x2),(y2),(startAng),(endAng),<(tolerance)>
  (one or more velocity, temperature, or concentration condition)
    ...
EndMoveLine

In XML files, a line is selected with:

<BCArc units='(units)' x1='(x1)' y1='(y1)' x2='(x2)' y2='(y2)'
       start='(startAng)' end='(endAng)' tolerance='(tolerance)'>
  (one or more velocity, temperature, or concentration condition)
    ...
</BCLine>

where

• (x1, y1) to (x2, y2) define (x, y) coordinates for the corners of a rectangular area enclosing the arc (or (R, Z) coordinates if axisymmetric). The units are mm (or determined by a units attribute in XML files).
• (startAng) and (endAng) give the start and end angle (in degrees) to specify the arc.
• (tolerance) is an optional tolerance. If it is omitted, the tolerance will be set to a small fraction of the grid's cell minimum cell size.

This command will apply velocity, temperature, and/or concentration boundary conditions to all nodes within (tolerance) the arc. The arc is traced in a counter-clockwise direction from (startAng) to (endAng) with angle = 0 corresponding to the position along the positive x axis.