r'''Calculates drag coefficient of a smooth sphere using the method in
    [1]_ as described in [2]_.

    .. math::
        C_D = \frac{24}{Re}10^E

        E = 0.383Re^{0.356}-0.207Re^{0.396} - \frac{0.143}{1+(\log_{10} Re)^2}

    Parameters
    ----------
    Re : float
        Reynolds number of the sphere, [-]

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

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

    Examples
    --------
    >>> Flemmer_Banks(200.)
    0.7849169609270039

    References
    ----------
    .. [1] Flemmer, R. L. C., and C. L. Banks. "On the Drag Coefficient of a
       Sphere." Powder Technology 48, no. 3 (November 1986): 217-21.
       doi:10.1016/0032-5910(86)80044-4.
    .. [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.

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

    .. math::
        C_D = \frac{24}{Re}10^E

        E = 0.383Re^{0.356}-0.207Re^{0.396} - \frac{0.143}{1+(\log_{10} Re)^2}

    Parameters
    ----------
    Re : float
        Reynolds number of the sphere, [-]

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

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

    Examples
    --------
    >>> Flemmer_Banks(200.)
    0.7849169609270039

    References
    ----------
    .. [1] Flemmer, R. L. C., and C. L. Banks. "On the Drag Coefficient of a
       Sphere." Powder Technology 48, no. 3 (November 1986): 217-21.
       doi:10.1016/0032-5910(86)80044-4.
    .. [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.
    '''
    E = 0.383*Re**0.356 - 0.207*Re**0.396 - 0.143/(1 + (log10(Re))**2)
    Cd = 24./Re*10**E
    return Cd