zone separate command

Syntax

zone separate keyword <range>

Primary keywords:

by-face

separates internal faces specified by the range. The gridpoints of the face are duplicated, and a new surface face is created. New faces and gridpoints get copies of all group and extra variable assignments belonging to the original face and gridpoint.

Note that faces may be restricted by giving two group range elements, therefore indicating that the face must be on the surface of the first and the second group. For instance, if Fred and George are group names assigned to zones, then

range group 'Fred' group 'George'

will select faces that are connected to zone of both group Fred and George. Also note that faces can be selected by group directly.

One (consistent) side of the newly created faces will have a new group assignment made, to make it easier to distinguish one side from the other after creation (since they will be in the same location in space). By default, the new side will be assigned the group NewSideX in slot Separate, where X is a number starting at 1 and incrementing with each zone separate command. The new-side keyword can be used to specify which side is assigned and the group and slot name used.

Note that this command uses a different algorithm than in past versions of FLAC3D, and should work correctly on zone regions that are not perfectly topologically connected, such as commonly result from a zone densify command. However this requires that only one surface with clear sides be created, if multiple intersecting surfaces are designed, use two zone separate by-face commands.

At this time, only one option to select faces for separation is available:

by-face

Attempts to separate all internal faces in the range.

clear-attach

By default, an error occurs if any gridpoint that has an attach condition associated with it is found among those to be separated. However, if the clear-attach keyword is supplied, then the separation of gridpoints will occur regardless. In addition, FLAC3D will remove any attach conditions connected to gridpoints affected.

new-side keyword

origin v

Specify a location in space used to determine which side is assigned to the new group. If the vector from the origin to the face centroid is in the opposite direction then the group name is assigned. This check is made to the first valid face encountered, and the side is kept consistent from then on. By default, the origin is (0,0,0).

group s <slot s >

Newly created faces will be assigned the group name name in the specified slot. The default slot, which is used if slot s is not supplied, is named Default. FLAC3D determines which face will be new and which one will be old by using the origin keyword. Use of the group logic is described in Group.