#=========================== numerical methods ================================
NUMERICAL_METHODS FLOW

  NEWTON_SOLVER
    MAX_ALLOW_LIQ_PRES_CHANGE_NI 1.d0
  /

  LINEAR_SOLVER
    SOLVER DIRECT
  /

END

#=========================== regression =======================================
REGRESSION
  CELLS_PER_PROCESS 5
END

#=========================== solver options ===================================

#=========================== discretization ===================================
GRID
  TYPE STRUCTURED
  NXYZ 5 1 5
  BOUNDS
    0.d0 0.d0 0.d0
    10.d0 1.d0 10.d0
  /
END

#=========================== characteristic curves ============================
CHARACTERISTIC_CURVES cc1
  SATURATION_FUNCTION VAN_GENUCHTEN
    ALPHA  1.d-4
    M 0.5d0
    LIQUID_RESIDUAL_SATURATION 0.1d0
  /
  PERMEABILITY_FUNCTION MUALEM_VG_LIQ
    M 0.5d0
    LIQUID_RESIDUAL_SATURATION 0.1d0
  /
END

#=========================== output options ===================================
OUTPUT
  TIMES y 0.01 0.1 1.0
  PERIODIC TIME 1. y
  FORMAT HDF5
END

#=========================== times ============================================
TIME
  FINAL_TIME 10.d0 y
  INITIAL_TIMESTEP_SIZE 1.d0 h
#  FINAL_TIME 0.15d0 y
#  INITIAL_TIMESTEP_SIZE 0.05d0 y
  MAXIMUM_TIMESTEP_SIZE 5.d-2 y
END

#=========================== regions ==========================================
REGION all
  COORDINATES
    -1.d20 -1.d20 -1.d20
     1.d20  1.d20  1.d20
  /
END

REGION top
  FACE TOP
  COORDINATES
    -1.d20 -1.d20 10.d0
     1.d20  1.d20 10.d0
  /
END

REGION bottom
  FACE BOTTOM
  COORDINATES
    -1.d20 -1.d20 0.d0
     1.d20  1.d20 0.d0
  /
END

REGION infiltrometer
  FACE TOP
  COORDINATES
    4.d0 -1.d20 10.d0
    8.d0  1.d20 10.d0
  /
END

REGION low_perm_zone
  FACE BOTTOM
  COORDINATES
    -1.d20 -1.d20 4.d0
     1.d20  1.d20 8.d0
  /
END

#=========================== flow conditions ==================================
FLOW_CONDITION initial
  TYPE
    LIQUID_PRESSURE HYDROSTATIC
  /
  DATUM 0.d0 0.d0 0.25d0
  LIQUID_PRESSURE 101325.d0
END

FLOW_CONDITION recharge
  TYPE
    LIQUID_FLUX NEUMANN
  /
  LIQUID_FLUX 10.d0 cm/y
END

#=========================== condition couplers ===============================
# initial condition
INITIAL_CONDITION
  FLOW_CONDITION initial
  REGION all
END

BOUNDARY_CONDITION outlet
  FLOW_CONDITION initial
  REGION bottom
END

BOUNDARY_CONDITION inlet
  FLOW_CONDITION recharge
  REGION infiltrometer
END

#=========================== stratigraphy couplers ============================
STRATA
  REGION all
  MATERIAL sand
END

STRATA
  REGION low_perm_zone
  MATERIAL silt
END

