Tutorial

Normal procedure

  • Obtain an appropriate sample UDF file for your purpose from our examples.
  • Start "Gourmet" and open the UDF file. Modify it for your own purpose and save it as "input.udf".
  • Run KAPSEL as follows. (remove "./" if you use Windows command prompt)
   > ./kapsel -Iinput.udf -Ooutput.udf -Ddefine.udf -Rrestart.udf
  • "-I" option defines the name of UDF file which contains details of simulation (type of simulation, initial conditions, physical and simulation parameters, etc...).
  • "-O" option defines the name of UDF file which contains the results (time-dependent positions and velocities of all the particles, etc...) of the simulation.
  • "-D" option defines the name of UDF file which contains definitions of KAPSEL data dormat. This is common for any simulations.
  • "-R" option defines the name of UDF file which contains values of all dynamical variables at the end of the simulation See "Re-start run" below.
  • Field data (fluid velocities, ionic densitied, etc...) is saved in a subdirectory specified in "input.udf" if "output.AVS" = "on". This requires huge disk space (GB order). No field data is saved if "output.AVS" = "off".
  • Start "Gourmet" and open "output.udf".
    • Instantaneous positions and velocities of all the particles can be seen as variables in "Particles[]". Use slide bar at the bottom of Gourmet window to see variables at different time steps.
    • Load "plot.py" to plot time evolutions of the variables. (See STEP4)
    • Load "particleshow.py" to visualize motions of particles. (See STEP4)

Re-start run

  • One can re-start simulations from the end of the previous run.
  • Start "Gourmet", and open "restart.udf"
  • Set "resume.Calculation" = "CONTINUE"
  • Increase "output.Num_step", and save it as "input2.udf"
  • Run KAPSEL as follows. (remove "./" if you use Windows command prompt)
   > ./kapsel -Iinput2.udf -Ooutput2.udf -Ddefine.udf -Rrestart2.udf