def Engelund_Hansen(Re):
    """Calculates drag coefficient of a smooth sphere using the method in
    [1]_ as described in [2]_.

    .. math::
        C_D = \\frac{24}{Re} + 1.5

    Parameters
    ----------
    Re : float
        Particle Reynolds number of the sphere using the surrounding fluid
        density and viscosity, [-]

    Returns
    -------
    Cd : float
        Drag coefficient [-]

    Notes
    -----
    Range is Re <= 2E5

    Examples
    --------
    >>> Engelund_Hansen(200.)
    1.62

    References
    ----------
    .. [1] F. Engelund, E. Hansen, Monograph on Sediment Transport in Alluvial
       Streams, Monograpsh Denmark Technical University, Hydraulic Lab,
       Denmark, 1967.
    .. [2] Barati, Reza, Seyed Ali Akbar Salehi Neyshabouri, and Goodarz
       Ahmadi. "Development of Empirical Models with High Accuracy for
       Estimation of Drag Coefficient of Flow around a Smooth Sphere: An
       Evolutionary Approach." Powder Technology 257 (May 2014): 11-19.
       doi:10.1016/j.powtec.2014.02.045.
    """
    return 24.0 / Re + 1.5
