9 Practical tips
9.1 Continuing an analysis
-
Copy the database from the previous calculation to a new file,
e.g. new.dat.
- Adjust control records like control_timestep, etc.
- Run a new calculation with new.dat.
9.2 Saving CPU time.
-
Post data items (post_point, etc.) slow down the calculation.
Skip them if you want to spare time.
- Printing (control_print, etc.) can substantially slow
down the calculation. If you know that a calculation
runs fine, only print the results at the end or so.
- Redirect printed output to a file and not to the screen.
A hard disk is faster then a screen.
9.3 Saving computer memory.
-
Try -options_matrix_group.
- Try -options_matrix_length (for the advanced user).
- Don’t use extreme large indices, since memory is allocated for all indices
up to the largest.
9.4 To model geometrically linear material
-
Use -fixed_in_space for options_mesh
- Use options_convection -no
- Use -updated_without_rotation for the material.
9.5 When you find yourself in times of troubles
-
Try the linear elements (-bar2, -tria3 and -tet4)!
- Try smaller time steps.
- Try control_timestep_iterations with at least 2.
- Try inertia (group_condif_density, group_condif_capacity, .. )
- Try relaxation (options_relaxation).