Running DES3D

dynearthsol2d input.cfg

or

dynearthsol3d input.cfg

• Several example input files are provided under examples/ directory. The format of the input file is described in examples/defaults.cfg.
• Benchmark cases with analytical solution can be found under benchmarks/ directory.
• Execute the executable with -h flag to see the available input parameters and their descriptions.

Progress reporting

The sim.info_display_step_interval parameter controls how often DES3D prints a status line to the screen:

info_display_step_interval = 10   # print progress every 10 simulation steps

This parameter replaced the older info_display_interval (which was wall-clock seconds) as of 2026. The value must be a positive multiple of mesh.quality_check_step_interval; DES3D will round it up automatically and notify you if an adjustment is made.

Checkpointing and restart

DES3D writes checkpoint files at regular intervals so that a simulation can be resumed after interruption. As of 2026, restarts are deterministic: a restarted run produces bit-for-bit identical output to one that never stopped. The following state is now fully persisted in the checkpoint:

• dt and dt_PT (time step)
• max_global_vel_mag
• reference_frame_time
• info_display_next_step
• dhacc (surface marker correction)
• strain_rate, viscosity, volume_old

To restart from a checkpoint, run the executable with the same config file. DES3D detects the most recent checkpoint automatically.

Run-time warnings

• While running, DES3D might print warnings on screen. An example is the warning about the potential race condition: e.g.,

****************************************************************
*    Warning: egroup-0 and egroup-2 might share common nodes.
*             There is some risk of racing conditions.
*             Please either increase the resolution or
*             decrease the number OpenMP threads.
****************************************************************

• Please do pay attention and follow given suggestions if any.