import math


def sherwood_slick(schmdt_nmbr, wind_speed, L, wat_kin_visc = 10**-6):
    """
    Return the average sherwood number for a slick []
    source : (HNS-MS)

    Parameters
    ----------
    schmdt_nmbr : Schmidt number []
    wind_speed : Wind speed (10 meters?) [m/s]
    L : Diameter of the slick [m]
    wat_kin_visc : Kinematic viscosity of water, the default is 10**-6 [m²/s]


    """
    re = wind_speed * L/ wat_kin_visc
    return 0.578 * schmdt_nmbr**(1/3) * math.sqrt(re)