*TRANSFORMF

Keyword type: model definition

This option may be used to specify a local axis system X'-Y'-Z' to be used for defining SPC's in CFD-calculations. For now, rectangular and cylindrical systems can be defined, triggered by the parameter TYPE=R (default) and TYPE=C.

A rectangular system is defined by specifying a point a on the local X' axis and a point b belonging to the X'-Y' plane but not on the X' axis. A right hand system is assumed (Figure ).

When using a cylindrical system two points a and b on the axis must be given. The X' axis is in radial direction, the Z' axis in axial direction from point a to point b, and Y' is in tangential direction such that X'-Y'-Z' is a right hand system (Figure ).

The difference with the *TRANSFORM card is that for CFD-calculations the SPC's are applied to element faces instead of nodes. The parameter SURFACE, specifying the surface for which the transformation applies, is required. Notice that this surface must be face-based.

First line:

• *TRANSFORM
• Enter the required parameter SURFACE, and the optional parameter TYPE if needed.

Second line:

• X-coordinate of point a.
• Y-coordinate of point a.
• Z-coordinate of point a.
• X-coordinate of point b.
• Y-coordinate of point b.
• Z-coordinate of point b.

Example:

*TRANSFORMF,SURFACE=ABC,TYPE=C
0.,0.,0.,1.,0.,0.

assigns a new cylindrical coordinate system to the faces belonging to surface ABC. The cylindrical axis is the global x-axis.

Example files: .