Coupling (Manually)

The present version has a capability for one-way coupling with other models such as NHWAVE or FUNWAVE-TVD itself. The nesting scheme passes surface elevation and velocity components calculated from other models or FUNWAVE-TVD in a large domain to a nested small domain through ghost cells at nesting boundaries. To run a nested model, the following procedures should be performed.

  1. The coupling option in Makefile should be defined as ‘-Dcoupling’. The program should be re–compiled.

  2. Prepare nesting data using the output of a large-domain model. The following is an example of the data format:

! coupling data

!  boundary info: num of points (negative means no point), start point


  -1,           1       ! (no data on east side)


   5,           1       ! (5 points at west boundary, start from  1)


  -1,           0       ! ( no data on south side)


  -1,           0       ! (no data on north side)


68.443001               ! (first step, NOTE: model clock will be initialized as this time)

EAST SIDE               ! (no nesting on east side)


   0.141220E-02    0.141220E-02    0.141220E-02   0.141220E-02    0.141220E-02     ! (u)

   -0.119260E-10    -0.119260E-10   -0.667390E-10  -0.667390E-10   -0.219240E-10   ! (v)

   0.141890E-02    0.141890E-02   0.141890E-02  0.141890E-02   0.141890E-02        ! (z)

SOUTH SIDE              ! (no nesting on south side)

NORTH SIDE              ! (no nesting on north side)

   68.641998            ! (next time step)


The example above is a case that a model nesting takes place at the WEST (left) boundary of a small domain. Boundaries are defined with the order: EAST, WEST, SOUTH, and NORTH. If the num of points of a boundary is larger than zero, the program will read a time series of (\(u, v, \eta\)) below ‘XXXX SIDE’. The read format is:

READ(11,*)         ! TIME_COUPLING_2

READ(11,119)       ! (U_COUPLING_EAST(I,2), I=1, N_COUPLING_EAST)

READ(11,119)       ! (V_COUPLING_EAST(I,2), I=1, N_COUPLING_EAST)

READ(11,119)       ! (Z_COUPLING_EAST(I,2), I=1, N_COUPLING_EAST)


119                ! FORMAT(5E16.6)

where N_COUPLING_EAST is the number of points at the EAST boundary.

  1. Specify the file of coupling data in “input.txt”:

    ! ----------------- COUPLING -------------------------
    ! if do coupling, have to set -DCOUPLING in Makefile
    COUPLING_FILE = coupling.txt

where “coupling.txt” is the file saved in procedure 2.