def Baroczy(x, rhol, rhog, mul, mug):
    r'''Calculates void fraction in two-phase flow according to the model of 
    [1]_ as given in [2]_, [3]_, and [4]_.

    .. math::
        \alpha = \left[1 + \left(\frac{1-x}{x}\right)^{0.74}\left(\frac{\rho_g}
        {\rho_l}\right)^{0.65}\left(\frac{\mu_l}{\mu_g}\right)^{0.13}
        \right]^{-1}
        
    Parameters
    ----------
    x : float
        Quality at the specific tube interval []
    rhol : float
        Density of the liquid [kg/m^3]
    rhog : float
        Density of the gas [kg/m^3]
    mul : float
        Viscosity of liquid [Pa*s]
    mug : float
        Viscosity of gas [Pa*s]

    Returns
    -------
    alpha : float
        Void fraction (area of gas / total area of channel), [-]

    Notes
    -----
    
    Examples
    --------
    >>> Baroczy(.4, 800, 2.5, 1E-3, 1E-5)
    0.9453544598460807

    References
    ----------
    .. [1] Baroczy, C. Correlation of liquid fraction in two-phase flow with 
       applications to liquid metals, Chem. Eng. Prog. Symp. Ser. 61 (1965) 
       179-191.
    .. [2] Xu, Yu, and Xiande Fang. "Correlations of Void Fraction for Two-
       Phase Refrigerant Flow in Pipes." Applied Thermal Engineering 64, no. 
       1-2 (March 2014): 242–51. doi:10.1016/j.applthermaleng.2013.12.032. 
    .. [3] Dalkilic, A. S., S. Laohalertdecha, and S. Wongwises. "Effect of 
       Void Fraction Models on the Two-Phase Friction Factor of R134a during 
       Condensation in Vertical Downward Flow in a Smooth Tube." International 
       Communications in Heat and Mass Transfer 35, no. 8 (October 2008): 
       921-27. doi:10.1016/j.icheatmasstransfer.2008.04.001.
    .. [4] Woldesemayat, Melkamu A., and Afshin J. Ghajar. "Comparison of Void 
       Fraction Correlations for Different Flow Patterns in Horizontal and 
       Upward Inclined Pipes." International Journal of Multiphase Flow 33, 
       no. 4 (April 2007): 347-370. doi:10.1016/j.ijmultiphaseflow.2006.09.004.
    '''
    Xtt = Lockhart_Martinelli_Xtt(x, rhol, rhog, mul, mug, 
                                  pow_x=0.74, pow_rho=0.65, pow_mu=0.13)
    return (1 + Xtt)**-1
r'''Calculates void fraction in two-phase flow according to the model of 
    [1]_ as given in [2]_, [3]_, and [4]_.

    .. math::
        \alpha = \left[1 + \left(\frac{1-x}{x}\right)^{0.74}\left(\frac{\rho_g}
        {\rho_l}\right)^{0.65}\left(\frac{\mu_l}{\mu_g}\right)^{0.13}
        \right]^{-1}
        
    Parameters
    ----------
    x : float
        Quality at the specific tube interval []
    rhol : float
        Density of the liquid [kg/m^3]
    rhog : float
        Density of the gas [kg/m^3]
    mul : float
        Viscosity of liquid [Pa*s]
    mug : float
        Viscosity of gas [Pa*s]

    Returns
    -------
    alpha : float
        Void fraction (area of gas / total area of channel), [-]

    Notes
    -----
    
    Examples
    --------
    >>> Baroczy(.4, 800, 2.5, 1E-3, 1E-5)
    0.9453544598460807

    References
    ----------
    .. [1] Baroczy, C. Correlation of liquid fraction in two-phase flow with 
       applications to liquid metals, Chem. Eng. Prog. Symp. Ser. 61 (1965) 
       179-191.
    .. [2] Xu, Yu, and Xiande Fang. "Correlations of Void Fraction for Two-
       Phase Refrigerant Flow in Pipes." Applied Thermal Engineering 64, no. 
       1-2 (March 2014): 242–51. doi:10.1016/j.applthermaleng.2013.12.032. 
    .. [3] Dalkilic, A. S., S. Laohalertdecha, and S. Wongwises. "Effect of 
       Void Fraction Models on the Two-Phase Friction Factor of R134a during 
       Condensation in Vertical Downward Flow in a Smooth Tube." International 
       Communications in Heat and Mass Transfer 35, no. 8 (October 2008): 
       921-27. doi:10.1016/j.icheatmasstransfer.2008.04.001.
    .. [4] Woldesemayat, Melkamu A., and Afshin J. Ghajar. "Comparison of Void 
       Fraction Correlations for Different Flow Patterns in Horizontal and 
       Upward Inclined Pipes." International Journal of Multiphase Flow 33, 
       no. 4 (April 2007): 347-370. doi:10.1016/j.ijmultiphaseflow.2006.09.004.