AFLR3 Tutorial – Growth Options
The following tutorial example cases demonstrate various capabilities within AFLR3 for controlling the point spacing field growth with an isotropic grid. These capabilities are also useful in controlling the point spacing in the isotropic grid region with a BL/SL/SNS grid. SolidMesh is used in the following sections to run the cases. A basic proficiency with SolidMesh is assumed. The data file for these cases is bar.SM.gz (right click to save/download the file). Alternatively, each of the cases can be run from a terminal window using the aflr3 script command. The surface grid files for these cases are bar.surf.gz, bar_control.surf.gz, and bar_control_ffx5.surf.gz.
The bar case is a simple case of a bar inside a box. The outer box is 100x100x100 with point spacing set to 4 and the inner box is 1x0.2x0.2 with point spacing set to 0.01.
An embedded/transparent surface is also included to control spacing near the bar. It is deactivated in the SolidMesh file provided and can be activated as needed. The control surface is 3x1.8x1.8 with point spacing set to 0.11.
1. INTERPOLATED AND SPECIFIED GROWTH
1.1. Default interpolated point spacing
Alternative Terminal Window AFLR3 Script Command
aflr3 bar.surf.gz –w
- Terminal Window
o run SolidMesh for case bar
sm –case bar.SM.gz
- SGen Panel
o deactivate surface groups for group Control
o generate surface grid
- VGen Panel
o set isotropic grid type
o generate volume grid
- Viz Panel
o read-in volume grid
o generate X-Y cutting plane
Typical output mesh
Tria Surface Faces = 28572
Nodes = 120156
Tet Elements = 669919
1.2. Specified growth point spacing
Alternative Terminal Window AFLR3 Script Command
aflr3 bar.surf.gz –w –grow1 –ogrid bar_growth1.b8.ugrid
- Terminal Window
o run SolidMesh for case bar
sm –case bar.SM.gz
- SGen Panel
o deactivate surface groups for group Control
o generate surface grid
- VGen Panel
o set isotropic grid type
o set moderate volume growth (growth rate is cdfr=1.2 and exclusion zone factor is cdfs=1.0)
o generate volume grid
- Viz Panel
o read-in volume grid
o generate X-Y cutting plane
Typical output mesh
Tria Surface Faces = 28572
Nodes = 39850
Tet Elements = 193275
1.3. Specified (lower) growth point spacing
Alternative Terminal Window AFLR3 Script Command
aflr3 bar.surf.gz –w –grow 1.1 –ogrid bar_grow_cdfr1,1.b8.ugrid
- Terminal Window
o run SolidMesh for case bar
sm –case bar.SM.gz
- SGen Panel
o deactivate surface groups for group Control
o generate surface grid
- VOpt Panel
o set new value for variable mdf to 2 (default growth rate is cdfr=1.1 and exclusion zone factor is cdfs=1.0)
- VGen Panel
o set isotropic grid type
o generate volume grid
- Viz Panel
o read-in volume grid
o generate X-Y cutting plane
Typical output mesh
Tria Surface Faces = 28572
Nodes = 79401
Tet Elements = 428448
1.4. Interpolated point spacing with increased growth rate limit
Alternative Terminal Window AFLR3 Script Command
aflr3 bar.surf.gz –w cdfr=1.3 –ogrid bar_cdfr1,3.b8.ugrid
- Terminal Window
o run SolidMesh for case bar
sm –case bar.SM.gz
- SGen Panel
o deactivate surface groups for group Control
o generate surface grid
- VOpt Panel
o set new value for variable cdfr to 1.3
- VGen Panel
o set isotropic grid type
o generate volume grid
- Viz Panel
o read-in volume grid
o generate X-Y cutting plane
Typical output mesh
Tria Surface Faces = 28572
Nodes = 96233
Tet Elements = 527829
1.5. Interpolated point spacing with a control surface
Alternative Terminal Window AFLR3 Script Command
aflr3 bar_control.surf.gz –w
- Terminal Window
o run SolidMesh for case bar
sm –case bar.SM.gz
- SGen Panel
o activate surface groups for group Control
o generate surface grid
- VGen Panel
o set isotropic grid type
o generate volume grid
- Viz Panel
o read-in volume grid
o generate X-Y cutting plane
Typical output mesh
Tria Surface Faces = 28572
Nodes = 126050
Tet Elements = 706139
1.6. Interpolated point spacing with a control surface and coarsened far-field
Alternative Terminal Window AFLR3 Script Command
aflr3 bar_control_ffx5.surf.gz –w
- Terminal Window
o run SolidMesh for case bar
sm –case bar.SM.gz
- SGen Panel
o activate surface groups for group Control
o select all 8 points on group FarField surface and increase their point spacing value from 4 to 20
o generate surface grid
- VGen Panel
o set isotropic grid type
o generate volume grid
- Viz Panel
o read-in volume grid
o generate X-Y cutting plane
Typical output mesh
Tria Surface Faces = 20414
Nodes = 85131
Tet Elements = 475541
