FF: Curl/Cartesian wake fixes and AWAE VTK wake-plane output

docs/source/user/fast.farm/InputFiles.rst

@@ -1134,31 +1134,62 @@ The sub-volume directories must follow the naming convention
    and ``1`` through **NumTurbines** for the high-resolution domain of
    each wind turbine.
 
--  *<index>* is a zero-padded integer index with the same field width as
-   **DirStartIndex**. The index for time step :math:`n` is
-   :math:`\text{DirStartNum} + n \times \Delta_\text{index}`, where
-   :math:`\text{DirStartNum}` is the integer value of **DirStartIndex**
-   and :math:`\Delta_\text{index}` is the stride between successive
-   directory indices (determined automatically by FAST.Farm by scanning
-   the available directories).
-
-During initialization, FAST.Farm reads the header of the starting
-sub-volume for each domain (low-resolution sub-volume 0 and each
-high-resolution sub-volume 1 through **NumTurbines**) to obtain the
-grid properties, then calls the directory-discovery routine to confirm
-that a sufficient number of time steps exist and that the grid
-properties are consistent across all time steps. Specifically, FAST.Farm
-verifies:
-
--  That at least **NumDT** low-resolution and high-resolution
-   directories are available for the simulation duration.
+-  *<index>* is an integer index, zero-padded to at least the field width
+   of **DirStartIndex** and widened as needed when the step counter grows
+   past that width.
+
+FAST.Farm does **not** assume a constant stride between successive
+directory indices. During initialization it reads the ``Header`` of each
+directory matching the prefix and assigns it to a time step by the
+simulation time recorded there: the directory used for time step
+:math:`n` is the one whose header time is
+:math:`t_\text{start} + n\,\Delta t`, where :math:`t_\text{start}` is the
+header time of the directory named by **DirStartIndex** and
+:math:`\Delta t` is **DT_Low-AMReX** for the low-resolution domain or
+**DT_High-AMReX** for the high-resolution domains.
+
+This supports precursor data written with a varying solver time step --
+for example an AMR-Wind run that transitions from ``time.initial_dt`` to
+``fixed_dt``, where the stride between directory indices changes but the
+output interval in time does not -- provided the output interval itself
+is uniform.
+
+Times are matched to within a tolerance of
+:math:`\max(10^{-6}\ \mathrm{s},\ 10^{-9}(|t_\text{start}| + |t|))`, which
+accommodates the floating-point drift accumulated by a long precursor
+simulation while remaining far tighter than a single output interval.
+
+Having obtained the grid properties from the starting sub-volume of each
+domain (low-resolution sub-volume 0 and each high-resolution sub-volume 1
+through **NumTurbines**), FAST.Farm verifies:
+
+-  That every required time step is represented by a directory: steps 0
+   through **NumDT** - 1 for the low-resolution domain, and steps 0
+   through (**NumDT** - 1) x (**DT_Low-AMReX** / **DT_High-AMReX**) for each
+   high-resolution domain. A time step matched by no directory (missing
+   data) is a fatal error naming the time step and its expected simulation
+   time, as is a time step matched by more than one of the directories
+   scanned (for example, overlapping output left behind by a restart). The
+   duplicate check is not exhaustive: the scan stops early once every
+   required step has been matched, so a stale duplicate at a higher
+   directory index than the first directory past the simulation window is
+   not read. Directories whose header time falls between two required
+   steps are ignored, so the LES may write its sub-volumes at a finer
+   cadence than FAST.Farm reads them, provided the FAST.Farm time step is
+   an integer multiple of the output interval.
 
 -  That the grid dimensions, origin, and spacing are identical across
    all time steps for a given sub-volume.
 
 -  That the grid dimensions are the same for all high-resolution
    sub-volumes (one per turbine).
 
+-  That every high-resolution sub-volume is written at the same
+   simulation times as sub-volume 1. FAST.Farm uses a single
+   **DT_High-AMReX** for the whole farm, so a sub-volume on a different
+   set of times would supply its turbine a different instant than the
+   rest of the farm.
+
 Because the grid properties are determined from the precursor data
 files, the user does not specify low- or high-resolution grid dimensions
 or origins in the FAST.Farm primary input file when using

glue-codes/fast-farm/src/FAST_Farm_Subs.f90

@@ -222,7 +222,11 @@ SUBROUTINE Farm_Initialize( farm, InputFile, ErrStat, ErrMsg )
    call AllocAry( farm%p%MaxNumPlanes, farm%p%NumTurbines, 'farm%p%MaxNumPlanes', ErrStat2, ErrMsg2);  CALL SetErrStat( ErrStat2, ErrMsg2, ErrStat, ErrMsg, RoutineName); if (Failed()) return
    do i=1,farm%p%NumTurbines
       ! Eventually, we will have different settings for different rotors
-      farm%p%MaxNumPlanes(i) = ceiling( 15.0 * ( WD_InitInput%InputFileData%NumDFull + WD_InitInput%InputFileData%NumDBuff ) / AWAE_InitInput%InputFileData%C_Meander )
+      if (WD_InitInput%InputFileData%Mod_Wake == Mod_Wake_Polar) then
+         farm%p%MaxNumPlanes(i) = ceiling( 18.0 * ( WD_InitInput%InputFileData%NumDFull + WD_InitInput%InputFileData%NumDBuff ) / AWAE_InitInput%InputFileData%C_Meander )
+      else
+         farm%p%MaxNumPlanes(i) = ceiling( 54.0 * ( WD_InitInput%InputFileData%NumDFull + WD_InitInput%InputFileData%NumDBuff ) )
+      endif
       farm%p%MaxNumPlanes(i) = max( 2, min( farm%p%MaxNumPlanes(i) , farm%p%n_TMax + 2 ) )
    end do
 
@@ -698,6 +702,12 @@ SUBROUTINE Farm_InitWD( farm, WD_InitInp, ErrStat, ErrMsg )
          WD_InitInp%TurbNum      = nt
          WD_InitInp%MaxNumPlanes = farm%p%MaxNumPlanes(nt)
          WD_InitInp%OutFileRoot  = farm%p%OutFileRoot
+         WD_InitInp%LowResBounds(1,1) = farm%p%X0_low
+         WD_InitInp%LowResBounds(2,1) = farm%p%Y0_low
+         WD_InitInp%LowResBounds(3,1) = farm%p%Z0_low
+         WD_InitInp%LowResBounds(1,2) = farm%p%X0_low + farm%p%dX_low * real(farm%p%nX_low - 1, ReKi)
+         WD_InitInp%LowResBounds(2,2) = farm%p%Y0_low + farm%p%dY_low * real(farm%p%nY_low - 1, ReKi)
+         WD_InitInp%LowResBounds(3,2) = farm%p%Z0_low + farm%p%dZ_low * real(farm%p%nZ_low - 1, ReKi)
 
             ! note that WD_Init has Interval as INTENT(IN) so, we don't need to worry about overwriting farm%p%dt_low here:
          call WD_Init( WD_InitInp, farm%WD(nt)%u, farm%WD(nt)%p, farm%WD(nt)%x, farm%WD(nt)%xd, farm%WD(nt)%z, &

modules/awae/CMakeLists.txt

@@ -26,6 +26,7 @@ add_library(awaelib STATIC
   src/AWAE.f90
   src/AWAE_IO.f90
   src/AWAE_Types.f90
+  src/AWAE_vtk.f90
   src/amrex_utils.F90
 )
 target_link_libraries(awaelib awaelib_c ifwlib nwtclibs)