# Test goal: Anisotropic molecular diffusion.
# Author: Jan Stebel
# Source for reference: qualitative
#   Two solutes are transported only by molecular diffusion
#   in the direction (2,1) and (1,2), respectively.
#   The magnitude of the diffusivity is 0.05 (the only positive eigenvalue).

flow123d_version: 4.0.0a01
problem: !Coupling_Sequential
  description: Anisotropic molecular diffusion
  mesh:
    mesh_file: ../00_mesh/square_1x1_xy.msh
  flow_equation: !Flow_Darcy_LMH
    input_fields:
      - region: .BOUNDARY
        bc_type: dirichlet
        bc_pressure: 0
    output:
      fields: []
  solute_equation: !Coupling_OperatorSplitting
    transport: !Solute_AdvectionDiffusion_DG
      input_fields:
        - region: .BOUNDARY
          bc_type: diffusive_flux
        - region: BULK
          diff_m:
            - !FieldConstant
              value: [ [ 0.04, 0.02, 0 ], [ 0.02, 0.01, 0 ], [ 0, 0, 0 ] ]
            - !FieldConstant
              value: [ [ 0.01, 0.02, 0 ], [ 0.02, 0.04, 0 ], [ 0, 0, 0 ] ]
          init_conc: !FieldFormula
            value: exp(-1e6*((X[0]-0.5)**2+(X[1]-0.5)**2)**4)
          dg_penalty: 10
      solver: !Petsc
        a_tol: 1.0e-12
        r_tol: 1.0e-12
      output:
        fields:
        - conc
        - diff_m
    output_stream: 
      format: !vtk
        variant: ascii
      times:
        - step: 0.1
      precision: 15
    substances: [ 1, 2 ]
    time:
      end_time: 1
    balance:
      cumulative: true
