def pyroII(h, kr, rho, cp, r):
    """
    Calculate the pyrolysis number Py II for a biomass particle.

    .. math:: Py^{II} = \\frac{h}{\\rho\\,C_p\\,R\\,K}

    Parameters
    ----------
    h : float
        Convective heat transfer coefficient [W/m²K]
    kr : float
        Rate constant [1/s]
    rho : float
        Density of the biomass particle [kg/m³]
    cp : float
        Heat capacity of the biomass particle [J/kgK]
    r : float
        Radius or characteristic length of the biomass particle [m]

    Returns
    -------
    pyII : float
        Pyrolysis number Py II [-]

    Example
    -------
    >>> pyroII(h=862.6129, kr=1.38556, rho=540, cp=3092.871049, r=0.0001847)
    2.018038

    References
    ----------
    D.L. Pyle and C.A. Zaror. Heat Transfer and Kinetics in the Low
    Temperature Pyrolysis of Solids. Chemical Engineering Science, vol. 39,
    no. 1, pg. 147-158, 1984.
    """
    pyII = h / (kr * rho * cp * r)
    return pyII