63 temperature = clamp(temperature, 1e-9, 500.0);
64 pressure = clamp(pressure, 0.0, 1e8);
70 constexpr Scalar M_x = 1e3*Xylene::molarMass();
71 constexpr Scalar M_w = 1e3*H2O::molarMass();
72 constexpr Scalar Tb_x = 412.9;
73 constexpr Scalar Tb_w = 373.15;
74 constexpr Scalar V_B_w = 18.0;
75 const Scalar sigma_w = 1.18*pow(V_B_w, 0.333);
76 constexpr Scalar T_scal_w = 1.15*Tb_w;
77 constexpr Scalar V_B_x = 140.4;
78 const Scalar sigma_x = 1.18*pow(V_B_x, 0.333);
79 const Scalar sigma_wx = 0.5*(sigma_w + sigma_x);
80 constexpr Scalar T_scal_x = 1.15*Tb_x;
81 const Scalar T_scal_wx = sqrt(T_scal_w*T_scal_x);
84 Scalar T_star = temperature/T_scal_wx;
85 T_star = max(T_star, 1e-5);
87 const Scalar Omega = 1.06036/pow(T_star, 0.1561) + 0.193/exp(T_star*0.47635)
88 + 1.03587/exp(T_star*1.52996) + 1.76474/exp(T_star*3.89411);
89 const Scalar B_ = 0.00217 - 0.0005*sqrt(1.0/M_w + 1.0/M_x);
90 const Scalar Mr = (M_w + M_x)/(M_w*M_x);
91 const Scalar D_wx = (B_*pow(temperature,1.6)*sqrt(Mr))
92 /(1e-5*pressure*power(sigma_wx, 2)*Omega);