ismip_f.sif

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!                                       !!
!! Test ISMIP HOM F000 - no sliding      !!
!!                                       !!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

check keywords warn
echo on
$L = 50.0e3
$Slope = 3.0 * pi / 180.0

$yearinsec = 365.25*24*60*60
$rhoi = 900.0/(1.0e6*yearinsec^2)   
$gravity = -9.81*yearinsec^2
$n = 1.0
$A = 2.140373e-01
$eta = 1.0/(2.0*A)

Header
  Mesh DB "." "rectangle"
End

Constants
! No needed
End


!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Simulation
  Coordinate System  = Cartesian 3D 
  Simulation Type ="Transient"

  Extruded Mesh Levels = Integer 16

  Timestepping Method = "bdf"
  BDF Order = 1
  Output Intervals = 1
  Timestep Intervals = 1000  
  Timestep Sizes = 1.0 

  Steady State Max Iterations = 8
  Steady State Min Iterations = 1
  Post File = "ismip_F001_.vtu"
  max output level = 20 
End
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!! the ice core (3d)
Body 1
  Name= "ice body"
  Equation = 1
  Body Force = 1
  Material = 1
  Initial Condition = 1
End

! Upper free surface
Body 2
  Name= "free surface"
  Equation = 2
  Material = 1
  Body Force = 2
  Initial Condition = 2
End


!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
! for ice core
Initial Condition 1
 Pressure = 0.0e0
 Velocity 1 = 0.0e0
 Velocity 2 = 0.0e0
 Velocity 3 = 0.0e0
End

!! for free surface
Initial Condition 2
  Zs = Real 0.0  
End

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Body Force 1
  Flow BodyForce 1 = Real $-gravity*sin(Slope)
  Flow BodyForce 2 = Real 0.0
  Flow BodyForce 3 = Real $gravity*cos(Slope)
End

!! accumulation flux in m/year
Body Force 2
   Accumulation Flux 1 = Real 0.0e0
   Accumulation Flux 2 = Real 0.0e0 
   Accumulation Flux 3 = Real 0.0e0 
End

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!! ice material properties in MPa - m - a system 
Material 1
  Density = Real $rhoi 
  Viscosity Model = String "power law"
  Viscosity = Real $eta                       
  Viscosity Exponent = Real 1.0               
  Critical Shear Rate = Real 1.0e-10
  
  ! Bed condition
  Min Zs = Real -1000.0
  Max Zs = Real +1.0e10
End

Solver 1  
  Equation = "MapCoordinate"
  Procedure = "StructuredMeshMapper" "StructuredMeshMapper"
  Active Coordinate = Integer 3

  Top Surface Variable Name = String "Zs"

  Mesh Velocity Variable = String "dSdt"
  Mesh Update Variable = String "dS"
  Mesh Velocity First Zero = Logical True
End

Solver 2
  Equation = "Navier-Stokes"
  
  Stabilization Method = String Stabilized
  Flow Model = Stokes

  Exported Variable 1 = -dofs 1 "dSdt" 
  Exported Variable 2 = -dofs 1 "dS" 

  Linear System Solver = Iterative      
  Linear System Iterative Method = BICGStab
  Linear System Preconditioning = ILU0
  Linear System Convergence Tolerance = Real 1.0e-8
  Linear System Max Iterations = 500

  Nonlinear System Max Iterations = 1  ! n=1
  Nonlinear System Convergence Tolerance  = 1.0e-5
  Nonlinear System Newton After Iterations = 3   
  Nonlinear System Newton After Tolerance = 1.0e-02
  Nonlinear System Relaxation Factor = 1.00
    
  Steady State Convergence Tolerance = Real 1.0e-4
End

Solver 3
  Equation = "Free Surface Top"
  Variable = String "Zs" 
  Variable DOFs =  1
  Exported Variable 1 = String "Zs Residual"
  Exported Variable 1 DOFs = 1

  Procedure = "FreeSurfaceSolver" "FreeSurfaceSolver"
  Before Linsolve = "EliminateDirichlet" "EliminateDirichlet"

  Linear System Solver = Iterative
  Linear System Max Iterations = 1500
  Linear System Iterative Method = BiCGStab
  Linear System Preconditioning = ILU0
  Linear System Convergence Tolerance = Real 1.0e-9
  Linear System Abort Not Converged = False
  Linear System Residual Output = 1

  Nonlinear System Max Iterations = 100
  Nonlinear System Convergence Tolerance  = 1.0e-6
  Nonlinear System Relaxation Factor = 1.00

  Steady State Convergence Tolerance = 1.0e-04

  Stabilization Method = Bubbles    
  Apply Dirichlet = Logical False ! No limiter needed for the upper surface

! How much the free surface is relaxed
  Relaxation Factor = Real 1.00       
End

Solver 4
  Exec Solver =  After TimeStep 
  Procedure = File "SaveData" "SaveLine"
  Filename =  "surface_F001.dat"
  File Append = Logical False
End

Solver 5
  Exec Solver =  After TimeStep 
  Equation = "Save Scalars"
  Procedure = "SaveData" "SaveScalars"
  Filename = "volume_F001.dat"
  File Append = Logical True 
  
  Variable 1 = String "flow solution"
  Operator 1 = String "Volume"

  Variable 2 = String "dSdt"
  Operator 2 = String "max abs"
End
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


Equation 1
  Active Solvers (4)= 1 2 4 5 
End

Equation 2
  Active Solvers (1) = 3
  Flow Solution Name = String "Flow Solution"
  Convection = String Computed
End
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!! BC  (y=y0)    
Boundary Condition 1
  Target Boundaries = 1
  Periodic BC = 3 
  Periodic BC Velocity 1  = Logical True
  Periodic BC Velocity 2  = Logical True
  Periodic BC Velocity 3  = Logical True
  Periodic BC Pressure = Logical True
  Periodic BC Zs  = Logical True
End

!!! BC (x=xmax) 
Boundary Condition 2
  Target Boundaries = 2
  Periodic BC = 4 
  Periodic BC Velocity 1  = Logical True
  Periodic BC Velocity 2  = Logical True
  Periodic BC Velocity 3  = Logical True
  Periodic BC Pressure = Logical True
  Periodic BC Zs  = Logical True
End

!!! BC (y=ymax)   
Boundary Condition 3
  Target Boundaries = 3
End

!!! BC  (x=x0) 
Boundary Condition 4
  Target Boundaries = 4
End

!!! bedrock
Boundary Condition 5
  Flow Force BC = Logical True

  Velocity 1 = 0.0e0
  Velocity 2 = 0.0e0
  Velocity 3 = 0.0e0
  
  Bottom Surface = Variable Coordinate 1, Coordinate 2
     Real MATC "-1000.0+100.0*exp(-(tx(0)*tx(0)+tx(1)*tx(1))/1.0e8)"
End

!!! free surface
Boundary Condition 6
  !!! this BC is equal to body no. 2 !!!
  Body Id = 2
  Save Line = Logical True
End