Hi, everyone. I am a beginner of PyLith. I am trying to simulate a 2D locked fault in a subduction zone. The mesh size at the fault is approximately 1 km. The mesh generated by Trelis has already passed quality checks. I used a back-slip model. The simulation duration is 500 years to attempt reaching a steady state. The surface displacement of the final year is treated as the surface velocity field. I set adaptive time stepping with a maximum time step of 2 years. I encountered PETSc errors. After attempts, the current setup allows the simulation to run.
[pylithapp.petsc]
pc_type = asm
sub_pc_factor_shift_type = nonzero
ksp_rtol = 1.0e-7
ksp_atol = 1.0e-9
ksp_max_it = 10000
ksp_gmres_restart = 100
ksp_monitor = true
#ksp_view = true
ksp_converged_reason = true
ksp_error_if_not_converged = true
snes_rtol = 1.0e-8
snes_atol = 1.0e-8
snes_max_it = 100
snes_monitor = true
#snes_view = true
snes_converged_reason = true
snes_error_if_not_converged = true
However, the current parameters seem to be much larger than those in Table 4.3 of the V2.2.2 manual, especially ksp_max_it. During the computation, the number of KSP iterations mostly ranges from 1000 to 2000. I want to know how to verify whether my parameter settings and calculation results are reliable.
Additional question:
Many VTK files were generated in my working directory. Where did I go wrong with my output settings?
Thank you in advance for your reply. Any comments would be helpful to me.