Thermal conductivity Eucken equation

Approximate values for the thermal conductivity of pure gases, up to moderate pressures, can be estimated from values of the gas viscosity, using Eucken s equation, Eucken (1911) ... 

Calculate the thermal conductivity. Thus, upon rearranging the Eucken equation,... 

A semiempirical Eucken equation is used to estimate the thermal conductivity of polyatomic gas with R = 1.987 cal/(molK). 

The Agari-Uno model (Agari and Uno 1986) shows that the thermal conductivity data are deviating from the Maxwell-Eucken equation at about a 10% volumetric fraction. At a high filler volume, the measured value was much higher than the prediction using existing correlations. This approach is based on series and parallel models and considers the crystaUmity of both phases and interfacial factor A, as shown in equation (11.5) ... 

Two frequently used estimation formulas are based on the original paper of Eucken (1913) and can be analyzed here in terms of the full theory. Starting from equations (4.26)-(4.28), that is, from the isotropic value for the thermal conductivity, it is assumed that there is no exchange of energy between translational and internal modes of motion. 

Equation (4.127) is written in a form that is suitable for the prediction of the properties of mixtures from independent evaluations, experimental or otherwise, of the thermal conductivity of the pure components, kq. It is, in fact, written in such a way that it automatically reproduces the pure component values and acts, therefore, as an interpolatory scheme between them which has its basis in a well-characterized approximation of the rigorous kinetic theory. However, further approximations are almost always required before the Hirschfelder-Eucken equation can be implemented. 

The evaluation of the excess contribution to the thermal conductivity of carbon dioxide-ethane mixtures has been performed by a route parallel to that employed for the viscosity. Again, that route has been described in detail in Section 5.5.1.2 so that here it is merely recorded that for pure carbon dioxide and pure ethane the thermal conductivity has been taken from the work of Vesovic et al. (1990, 1994). All other quantities required for the calculation are the same as those employed for the zero-density thermal conductivity. In this context it should be noted that the Thome-Enskog equations employed for these calculations have, as their zero-density limit, the Hirschfelder-Eucken result in the form of equation (15.5). Figure 15.3 contains the pseudo-radial distribution functions for carbon dioxide and ethane determined... 

---