def calculate_thermal_diffusivity(thermal_conductivity, density, specific_heat_capacity):
    """
    Returns thermal diffusivity from thermal conductivity.
    alpha = k/(rho*c_p)
    :param thermal_conductivity:
    :param density:
    :param specific_heat_capacity:
    :return:
    """
    diffusivity = thermal_conductivity / (density * specific_heat_capacity)
    return diffusivity