gcr_cmg_sgs.sif

! Simple 2d linear elasticity bending problem.
! Here the monolithic matrix is split into a block matrix
! and then the block matrix strategy is used to solve it.
!
! Compared to base case here we used cmg instead of amg.

Header
  CHECK KEYWORDS Warn
  Mesh DB "." "angle"
  Include Path ""
  Results Directory ""
End

Simulation
  Max Output Level = 5
  Coordinate System = "Cartesian"
  Coordinate Mapping(3) = 1 2 3

  Simulation Type = "Steady State"
  Steady State Max Iterations = 1
  Steady State Min Iterations = 1
  Output Intervals = 1

!  Post File = "case.ep"
End

Constants
  Gravity(4) = 0 -1 0 9.82
  Stefan Boltzmann = 5.67e-08
End

Body 1
  Name = "Body1"
  Equation = 1
  Material = 1
  Body Force = 1
End


Equation 1
  Name = "Both"
  Active Solvers(1) = 1
End


Solver 1
  Equation = "lin.elast"

  Optimize Bandwidth = False
  Linear System Scaling = True

  Procedure = "StressSolve" "StressSolver"
  Variable = String "Disp"
  Variable DOFs = Integer 2
  Calculate Stresses = False
  Displace Mesh = Logical False

  Steady State Convergence Tolerance = 1.0e-05
  Nonlinear System Relaxation Factor = Real 1.0
  Nonlinear System Max Iterations = Integer 1

! These choose the overall block strategies
!-----------------------------------------
  Block Solver = Logical True
  Block Preconditioner = Logical True
  Block Gauss-Seidel = Logical True
  Block Matrix Reuse = Logical True

! Linear system solver for outer loop
!-----------------------------------------
  Outer: Linear System Solver = string "Iterative"
  Outer: Linear System Convergence Tolerance = real 1e-8
  Outer: Linear System Iterative Method = string GCR
  Outer: Linear System GCR Restart = Integer 50
  Outer: Linear System Residual Output = integer 1
  Outer: Linear System Max Iterations = integer 200

! Linear system solver for blocks
!-----------------------------------------
  Linear System Solver = multigrid	
  Linear System Convergence Tolerance = 1.0e-05
  Multigrid Levels = Integer 10

!--- basic algebraic multigrid iteration stuff
  MG Levels = Integer 10
  MG Smoother = String sgs
  MG Pre Smoothing Iterations(1) = 1
  MG Post Smoothing Iterations(1) = 1
 
!--- cluster MG specific parameters
  MG Method = String cluster
  MG Cluster Size = Integer 0
  MG Cluster Alpha = Real 1.8
  MG Strong Connection Limit = Real 0.01
! MG Strong Connection Minimum = Integer 4
  MG Max Iterations = Integer 2
End  

Material 1
  Name = "Ideal"

  Youngs modulus = 1
  Poisson Ratio  = 0.35
  Density = 1.0
End 

Body Force 1 
  Name = "bodyforce"
  Stress BodyForce 1 = Real 1.0
!  Stress BodyForce 2 = Real -1.0
End


Boundary Condition 1
  Target Boundaries(1) = 1 

  Disp 1 = Real 0
  Disp 2 = Real 0
End

Solver 1 :: Reference Norm = Real 0.23581335