def eta_n2(T):
# See Cole1985
# Units of g/cm/s = 0.1 Pa s
eta0 = np.array([8.24, 8.85, 9.45, 10.05, 12.88, 15.48, 17.90])
T0 = np.array([120, 130, 140, 150, 200, 250, 300])
eta0 = eta0*1e-6
eta_n2 = pd.extrap(T,T0,eta0)
return eta_n2
def eta_he(T):
# See Amdur1947
# Units of Poise = g/cm/s = 0.1 Pa s
eta0 = np.array([0.549, 1.277, 2.846, 3.147, 3.523, 8.205, 8.845, 9.470, 10.095,
10.680, 11.255, 11.815, 12.365, 12.90, 13.43, 13.95, 14.46, 14.96])
T0 = np.array([1.64, 4.23, 14.21, 16.55, 20.38, 80, 90, 100, 110, 120, 130, 140,
150, 160, 170, 180, 190, 200])
eta0 = np.append(eta0,19)
eta0 = eta0*1e-6
T0 = np.append(T0,300)
eta_he = pd.extrap(T,T0,eta0)
return eta_he
