Example 2. Interlocking rings

The following example is composed of two rings of constant cross-section that can be swept along their axes. The problem here is that the rings overlap, forming a tetrahedral shape which cannot be swept. The key to solving this problem is separating out the region of overlap, explicitly setting the source and target surfaces, and using the tetprimitive scheme on the tetrahedral region.

Suggested webcuts

Webcut Command

CUBIT> webcut body 1 plane surface 5

CUBIT> webcut body 2 sheet extended from surface 4

CUBIT> webcut body 3 plane surface 12

CUBIT> webcut body 4 sheet extended from surface 10
CUBIT> imprint all
CUBIT> merge all

There are five volumes that result from the webcutting. Two of them are automatically sweepable. Two of them must have their schemes set explicitly, and one of them is meshed using the tetprimitive scheme.

Webcut Command

One-to-one Sweepable

Source and target are set automatically using autoscheme

CUBIT> volume 1 3 scheme auto

One-to-one Sweepable

Must have source and target set explicitly

CUBIT> volume 2 scheme sweep source 17 target 7
CUBIT> volume 4 scheme sweep source 29 target 18

Non-sweepable

Use the tetprimitive scheme

CUBIT> curve in volume 5 interval 6
CUBIT> volume 5 scheme tetprimitive
CUBIT> volume all size 0.5
CUBIT> mesh volume all

Final mesh

The final mesh is created at a size of 0.5 for all volumes.