docs: def turbulent_Webb(Re, Pr, fd):
      r'''Calculates internal convection Nusselt number for turbulent flows
      in pipe according to [2]_ as in [1]_.
  
      .. math::
          Nu = \frac{(f/8)RePr}{1.07 + 9(f/8)^{0.5}(Pr-1)Pr^{1/4}}
  
      Parameters
      ----------
      Re : float
          Reynolds number, [-]
      Pr : float
          Prandtl number, [-]
      fd : float
          Darcy friction factor [-]
  
      Returns
      -------
      Nu : float
          Nusselt number, [-]
  
      Notes
      -----
      Range according to [1]_ is 0.5 < Pr ≤ 100  and 10^4 ≤ Re ≤ 5*10^6
  
      Examples
      --------
      >>> turbulent_Webb(Re=1E5, Pr=1.2, fd=0.0185)
      239.10130376815872
  
      References
      ----------
      .. [1] Rohsenow, Warren and James Hartnett and Young Cho. Handbook of Heat
         Transfer, 3E. New York: McGraw-Hill, 1998.
      .. [2] Webb, Dr R. L. “A Critical Evaluation of Analytical Solutions and
         Reynolds Analogy Equations for Turbulent Heat and Mass Transfer in
         Smooth Tubes.” Wärme - Und Stoffübertragung 4, no. 4
         (December 1, 1971): 197–204. doi:10.1007/BF01002474.
      '''
      return (fd/8.)*Re*Pr/(1.07 + 9.*(fd/8.)**0.5*(Pr - 1.)*Pr**0.25)