friction_factor_katheder_der Function

public function friction_factor_katheder_der(c_pt, Re) result(friction_der) bind(C)

Arguments

Type IntentOptional Attributes Name
type(c_ptr), value :: c_pt
real(kind=dp), value :: Re

Return Value real(kind=dp)


Source Code

  function friction_factor_katheder_der(c_pt,Re) result(friction_der) bind(C)
    type(c_ptr), value :: c_pt
    real(dp), value :: Re
    real(dp) :: friction_der
    type(katheder_cfg_t), pointer :: katheder_ptr
    call c_f_pointer(c_pt,katheder_ptr)

    if(Re > katheder_ptr%Re_min) then
      friction_der=-0.25_dp*19.5_dp*katheder_ptr%beta*(Re**(-katheder_ptr%beta-1.0_dp))/(katheder_ptr%VoidFr**0.742_dp)
    else
      friction_der=0.0_dp
    endif
  end function friction_factor_katheder_der