Commands & Concepts¶

spparks input file¶

• Run spparks:

  # SPPARKS 'potts' model for modeling 'grain' growth
  let N=128
  let Q=2048
  let P=$Q+1
  kT="0.85"
  spk_flame.gnu -var kT $kT -var N $N  -var Q $Q -var P $P < grain_growth.in
  

• Download 'grain_growth.in'

  # SPPARKS 'potts' model for modeling 'grain' growth
  # let N=128
  # let Q=2048
  # let P=$Q+1
  # kT="0.25"
  # spk_flame.gnu -var kT $kT -var N $N  -var Q $Q -var P $P < grain_growth.in
  
  seed		 56689
  
  # Use 'Potts' app to simulate grain growth;
  # Site 'spins' can assume values of its nearest neighbors.
  app_style	 potts/pin ${Q}
  
  # 2d lattice; Each site has 8 neighbors
  dimension	 2
  lattice		 sq/8n 1.0
  
  # Define lattice extent called 'square'; 
  region		 square block 0 ${N} 0 ${N} -1.0 1.0
  
  # Define 'axis' aligned simulation domain on 'square'
  create_box	 square
  
  # Creates sites on lattice defined above; also creates neighborhood list for each site
  create_sites     box
  
  # Initializes sites randomly with values between 1 and 2048
  set site range 1 ${Q}
  
  # Now pin 1% of sites (including their neighbors (multiflag=1))
  # Pin value = Q+1
  pin .01 1 0
  
  # Simulation temperature; Units of energy
  temperature	 ${kT}
  
  # KMC solver
  solve_style      tree
  # sectors are required to run 'tree' kmc in parallel
  sector yes
  
  # Diagnostic style energy computes the total energy for all sites
  diag_style       energy
  
  # Print diagnostic information to screen and log file every 50.0 seconds
  stats            50.0
  
  # Write snapshot of site values to 'grain_growth.dump' every 25.0 seconds 
  dump  1 text  25.0 grain_growth.dump
  
  # Write 'image'; boundary between grains drawn with color = 0 0 0 aka 'black'
  dump grain_growth_image image 50 grain_growth.*.jpg site site crange 1 ${Q} drange 1 1 view 0.0 0.0 boundary site 1 shape cube box no 1 zoom 1.95
  dump_modify grain_growth_image boundcolor black backcolor white scolor ${P} black pad 4
  
  # Write 'cluster/grain' diagnostics
  diag_style       cluster stats no delt 25.0 filename grain_growth.cluster
  
  # Run for 1400 *spparks* steps
  run              1400.0
  

[1]	https://www.uwgb.edu/dutchs/symmetry/bravais.htm