def Yu_France(m, x, rhol, rhog, mul, mug, D, roughness=0, L=1):
    r'''Calculates two-phase pressure drop with the Yu, France, Wambsganss,
    and Hull (2002) correlation given in [1]_ and reviewed in [2]_ and [3]_.

    .. math::
        \Delta P = \Delta P_{l} \phi_{l}^2

    .. math::
        \phi_l^2 = X^{-1.9}

    .. math::
        X = 18.65\left(\frac{\rho_g}{\rho_l}\right)^{0.5}\left(\frac{1-x}{x}
        \right)\frac{Re_{g}^{0.1}}{Re_l^{0.5}}

    Parameters
    ----------
    m : float
        Mass flow rate of fluid, [kg/s]
    x : float
        Quality of fluid, [-]
    rhol : float
        Liquid density, [kg/m^3]
    rhog : float
        Gas density, [kg/m^3]
    mul : float
        Viscosity of liquid, [Pa*s]
    mug : float
        Viscosity of gas, [Pa*s]
    D : float
        Diameter of pipe, [m]
    roughness : float, optional
        Roughness of pipe for use in calculating friction factor, [m]
    L : float, optional
        Length of pipe, [m]

    Returns
    -------
    dP : float
        Pressure drop of the two-phase flow, [Pa]

    Notes
    -----

    Examples
    --------
    >>> Yu_France(m=0.6, x=.1, rhol=915., rhog=2.67, mul=180E-6, mug=14E-6,
    ... D=0.05, roughness=0, L=1)
    1146.983322553957

    References
    ----------
    .. [1] Yu, W., D. M. France, M. W. Wambsganss, and J. R. Hull. "Two-Phase
       Pressure Drop, Boiling Heat Transfer, and Critical Heat Flux to Water in
       a Small-Diameter Horizontal Tube." International Journal of Multiphase
       Flow 28, no. 6 (June 2002): 927-41. doi:10.1016/S0301-9322(02)00019-8.
    .. [2] Kim, Sung-Min, and Issam Mudawar. "Universal Approach to Predicting
       Two-Phase Frictional Pressure Drop for Adiabatic and Condensing Mini/
       Micro-Channel Flows." International Journal of Heat and Mass Transfer
       55, no. 11-12 (May 2012): 3246-61.
       doi:10.1016/j.ijheatmasstransfer.2012.02.047.
    .. [3] Xu, Yu, Xiande Fang, Xianghui Su, Zhanru Zhou, and Weiwei Chen.
       "Evaluation of Frictional Pressure Drop Correlations for Two-Phase Flow
       in Pipes." Nuclear Engineering and Design, SI : CFD4NRS-3, 253 (December
       2012): 86-97. doi:10.1016/j.nucengdes.2012.08.007.
    '''
    # Actual Liquid flow
    v_l = m*(1-x)/rhol/(pi/4*D**2)
    Re_l = Reynolds(V=v_l, rho=rhol, mu=mul, D=D)
    fd_l = friction_factor(Re=Re_l, eD=roughness/D)
    dP_l = fd_l*L/D*(0.5*rhol*v_l**2)

    # Actual gas flow
    v_g = m*x/rhog/(pi/4*D**2)
    Re_g = Reynolds(V=v_g, rho=rhog, mu=mug, D=D)

    X = 18.65*(rhog/rhol)**0.5*(1-x)/x*Re_g**0.1/Re_l**0.5
    phi_l2 = X**-1.9
    return phi_l2*dP_l