def d_out_dist_cooler(P_mass, rho_dist_cool, w_drift):
    """
    Calculates the tube's diameter of out distilliat from distilliat cooler to distilliat volume.
    Parameters
    ----------
    P_mass : float
        The mass flow rate of distilliat, [kg/s]
    rho_dist_cool : float
        The density of liquid at cooling temperature, [kg/m**3]
    w_drift :float
        The speed of steam at the tube, [m/s]
    Returns
    -------
    d_out_dist_cooler : float
        The tube's diameter of out distilliat from distilliat cooler to distilliat volume, [m]
    References
    ----------
    &&&
    """  
    return P_mass/(0,785*rho_dist_cool*w_drift)