translation_source_term.f90

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module translation_source_term
  use num_types, only : rp
  use field_list, only : field_list_t
  use json_module, only : json_file
  use json_utils, only: json_get_or_lookup, json_get_or_lookup_or_default
  use source_term, only : source_term_t
  use coefs, only : coef_t
  use neko_config, only : neko_bcknd_device
  use utils, only : neko_error
  use field, only : field_t
  use field_math, only : field_col3, field_add2
  use operators, only : div
  use device, only : device_sync
  use registry, only : neko_registry
  use time_state, only : time_state_t
  use scratch_registry, only : neko_scratch_registry
  implicit none
  private
 
  type, public, extends(source_term_t) :: translation_source_term_t
     real(kind=rp) :: domain_vel(3)
   contains
     procedure, pass(this) :: init => translation_source_term_init_from_json
     procedure, pass(this) :: init_from_components => &
          translation_source_term_init_from_components
     procedure, pass(this) :: free => translation_source_term_free
     procedure, pass(this) :: compute_ => translation_source_term_compute
  end type translation_source_term_t
 
contains
  subroutine translation_source_term_init_from_json(this, json, fields, coef, &
       variable_name)
    class(translation_source_term_t), intent(inout) :: this
    type(json_file), intent(inout) :: json
    type(field_list_t), intent(in), target :: fields
    type(coef_t), intent(in), target :: coef
    character(len=*), intent(in) :: variable_name
    real(kind=rp), allocatable :: domain_vel(:)
    ! Alternative parameters to set the rotation vector
    real(kind=rp) :: start_time, end_time
 
    call json_get_or_lookup_or_default(json, "start_time", start_time, 0.0_rp)
    call json_get_or_lookup_or_default(json, "end_time", end_time, huge(0.0_rp))
 
    if (json%valid_path("domain_velocity")) then
       call json_get_or_lookup(json, "domain_velocity", domain_vel)
 
       if (size(domain_vel) .ne. 3) then
          call neko_error("The domain velocity should have 3 components.")
       end if
    else
       allocate(domain_vel(3))
       domain_vel = 0.0_rp
    end if
 
    call translation_source_term_init_from_components(this, fields, &
         domain_vel, coef, start_time, end_time)
 
  end subroutine translation_source_term_init_from_json
 
  subroutine translation_source_term_init_from_components(this, fields, &
       domain_vel, coef, start_time, end_time)
    class(translation_source_term_t), intent(inout) :: this
    class(field_list_t), intent(in), target :: fields
    real(kind=rp), intent(in) :: domain_vel(3)
    type(coef_t) :: coef
    real(kind=rp), intent(in) :: start_time
    real(kind=rp), intent(in) :: end_time
 
    call this%free()
    call this%init_base(fields, coef, start_time, end_time)
 
    if (fields%size() .ne. 3) then
       call neko_error("Number of fields for the translation force must be 3.")
    end if
 
    this%domain_vel = domain_vel
  end subroutine translation_source_term_init_from_components
 
  subroutine translation_source_term_free(this)
    class(translation_source_term_t), intent(inout) :: this
 
    call this%free_base()
  end subroutine translation_source_term_free
 
  subroutine translation_source_term_compute(this, time)
    class(translation_source_term_t), intent(inout) :: this
    type(time_state_t), intent(in) :: time
    type(field_t), pointer :: u, v, w
    type(field_t), pointer :: work1, work2, work3
    type(field_t), pointer :: work4, work5, work6, work7
    integer :: tmp_index(7)
    type(field_t), pointer :: fx, fy, fz
 
    u => neko_registry%get_field("u")
    v => neko_registry%get_field("v")
    w => neko_registry%get_field("w")
 
    fx => this%fields%get_by_index(1)
    fy => this%fields%get_by_index(2)
    fz => this%fields%get_by_index(3)
 
 
    call neko_scratch_registry%request_field(work1, tmp_index(1), .false.)
    call neko_scratch_registry%request_field(work2, tmp_index(2), .false.)
    call neko_scratch_registry%request_field(work3, tmp_index(3), .false.)
    call neko_scratch_registry%request_field(work4, tmp_index(4), .false.)
    call neko_scratch_registry%request_field(work5, tmp_index(5), .false.)
    call neko_scratch_registry%request_field(work6, tmp_index(6), .false.)
    call neko_scratch_registry%request_field(work7, tmp_index(7), .false.)
 
 
    ! Assign the velocities
    work1 = this%domain_vel(1)
    work2 = this%domain_vel(2)
    work3 = this%domain_vel(3)
 
    ! umesh_j * du/dx_j = div (umesh u) - u * div umesh but
    ! div umesh = 0 so we just calculate div (umesh u)
    call field_col3(work4, u, work1, u%size())
    call field_col3(work5, u, work2, u%size())
    call field_col3(work6, u, work3, u%size())
    call div(work7%x, work4%x, work5%x, work6%x, this%coef)
    call field_add2(fx, work7, work7%size())
 
    ! umesh_j * dv/dx_j
    call field_col3(work4, v, work1, v%size())
    call field_col3(work5, v, work2, v%size())
    call field_col3(work6, v, work3, v%size())
    call div(work7%x, work4%x, work5%x, work6%x, this%coef)
    call field_add2(fy, work7, work7%size())
 
    ! umesh_j * dw/dx_j
    call field_col3(work4, w, work1, w%size())
    call field_col3(work5, w, work2, w%size())
    call field_col3(work6, w, work3, w%size())
    call div(work7%x, work4%x, work5%x, work6%x, this%coef)
    call field_add2(fz, work7, work7%size())
 
    call device_sync()
 
    ! Release the scratch fields
    call neko_scratch_registry%relinquish_field(tmp_index)
 
    nullify(u, v, w, fx, fy, fz)
 
    nullify(work1, work2, work3, work4, work5, work6, work7)
 
 
  end subroutine translation_source_term_compute
 
end module translation_source_term