| Author | Message | ||
     Jerry Brown (jerrybrown11743) Member Username: jerrybrown11743 Post Number: 51 Registered: 03-2004 |
There was a mention of GROW3 in a recent post. It apparently is used for mesh control. I can't find any reference to it in HELP. What is this? | ||
| Robert G. Nelson (rgnelson) Moderator Username: rgnelson Post Number: 1187 Registered: 06-2003 |
GROW3 controls the rate at which 3D cell sizes can increase as a function of distance from boundary features. A cell at a distance D from a boundary feature of size F can be at most F+Grow3*D in size. The actual size is limited to the minimum of all competing controls, including Mesh_Spacing controls. The default value of GROW3 is 0.25. Mesh generation is very sensitive to this number, and it is easier to break a mesh by twiddling it than to cure one. But sometimes it is useful. We have never done a complete study of the behavior of this control, but I would guess it should never be over 0.35 or under 0.15. There is an analogous control GROW2 for 2D meshes. It defaults to 0.3 in 2D problems. In 3D problems it defaults to 0.25 for surface and sidewall meshes, and should be kept consistent with GROW3 in 3D problems. | ||
| Jerry Brown (jerrybrown11743) Member Username: jerrybrown11743 Post Number: 52 Registered: 03-2004 |
Thanks. Looks like something better left alone. | ||
| Robert G. Nelson (rgnelson) Moderator Username: rgnelson Post Number: 1188 Registered: 06-2003 |
Unless a mesh generation is failing, there is no point in playing with the growth factors. |