entropy_viscosity_cpu.f90

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module entropy_viscosity_cpu
  use num_types, only : rp
  implicit none
  private
 
  public :: entropy_viscosity_compute_residual_cpu, &
       entropy_viscosity_compute_viscosity_cpu, &
       entropy_viscosity_apply_element_max_cpu, &
       entropy_viscosity_clamp_to_low_order_cpu, &
       entropy_viscosity_smooth_divide_cpu
 
contains
 
  subroutine entropy_viscosity_compute_residual_cpu(entropy_residual, &
       S, S_lag1, S_lag2, S_lag3, bdf_coeffs, dt, n)
    integer, intent(in) :: n
    real(kind=rp), dimension(n), intent(out) :: entropy_residual
    real(kind=rp), dimension(n), intent(in) :: s, s_lag1, s_lag2, s_lag3
    real(kind=rp), intent(in) :: bdf_coeffs(4)
    real(kind=rp), intent(in) :: dt
    integer :: i
 
    do concurrent(i = 1:n)
       entropy_residual(i) = (bdf_coeffs(1) * s(i) &
            - bdf_coeffs(2) * s_lag1(i) &
            - bdf_coeffs(3) * s_lag2(i) &
            - bdf_coeffs(4) * s_lag3(i)) / dt
    end do
 
  end subroutine entropy_viscosity_compute_residual_cpu
 
  subroutine entropy_viscosity_compute_viscosity_cpu(reg_coeff, &
       entropy_residual, h, c_avisc_entropy, n_S, n)
    integer, intent(in) :: n
    real(kind=rp), dimension(n), intent(out) :: reg_coeff
    real(kind=rp), dimension(n), intent(in) :: entropy_residual, h
    real(kind=rp), intent(in) :: c_avisc_entropy, n_s
    integer :: i
 
    do concurrent(i = 1:n)
       reg_coeff(i) = c_avisc_entropy * h(i) * h(i) * entropy_residual(i) / n_s
    end do
 
  end subroutine entropy_viscosity_compute_viscosity_cpu
 
  subroutine entropy_viscosity_apply_element_max_cpu(reg_coeff, lx, nelv)
    integer, intent(in) :: lx, nelv
    real(kind=rp), dimension(lx, lx, lx, nelv), intent(inout) :: reg_coeff
    integer :: i, j, k, el
    real(kind=rp) :: max_visc_el
 
    do el = 1, nelv
       max_visc_el = 0.0_rp
 
       do k = 1, lx
          do j = 1, lx
             do i = 1, lx
                max_visc_el = max(max_visc_el, reg_coeff(i, j, k, el))
             end do
          end do
       end do
 
       do k = 1, lx
          do j = 1, lx
             do i = 1, lx
                reg_coeff(i, j, k, el) = max_visc_el
             end do
          end do
       end do
    end do
 
  end subroutine entropy_viscosity_apply_element_max_cpu
 
  subroutine entropy_viscosity_clamp_to_low_order_cpu(reg_coeff, &
       h, max_wave_speed, c_avisc_low, n)
    integer, intent(in) :: n
    real(kind=rp), dimension(n), intent(inout) :: reg_coeff
    real(kind=rp), dimension(n), intent(in) :: h, max_wave_speed
    real(kind=rp), intent(in) :: c_avisc_low
    integer :: i
    real(kind=rp) :: low_order_visc
 
    do concurrent(i = 1:n)
       low_order_visc = c_avisc_low * h(i) * max_wave_speed(i)
       reg_coeff(i) = min(reg_coeff(i), low_order_visc)
    end do
 
  end subroutine entropy_viscosity_clamp_to_low_order_cpu
 
  subroutine entropy_viscosity_smooth_divide_cpu(reg_coeff, &
       temp_field, mult_field, n)
    integer, intent(in) :: n
    real(kind=rp), dimension(n), intent(out) :: reg_coeff
    real(kind=rp), dimension(n), intent(in) :: temp_field, mult_field
    integer :: i
 
    do concurrent(i = 1:n)
       reg_coeff(i) = temp_field(i) / mult_field(i)
    end do
 
  end subroutine entropy_viscosity_smooth_divide_cpu
 
end module entropy_viscosity_cpu