Viscosity estimation

C. E. Morriss, R. Freedman, C. Straley, M. Johnston, H. J. Vinegar, P. N. Tu-tunjian 1997, (Hydrocarbon saturation and viscosity estimation from NMR logging in the Belridge diatomite), Log Analyst 38 (2), 44-59. 

Table III. Measured Relative Molecular Weight, Passed Through GPC and Reduced Viscosities. Estimated Intrinsic Viscosities of Polymers Columns in Benzene ...

For a gas, the effect of pressure on the viscosity depends on the region of P and T of interest relative to the critical point. Near the critical state, the change in viscosity with T at constant pressure can be very large. The correlation of Uyehara and Watson [15] is presented for the reduced viscosity estimated from the corresponding-states method. The critical viscosities of a few gases and liquids are available [15]. These are necessary to calculate the... 

The molecular weight of toluene is 93 kg/kmol, so the critical viscosity estimated from eqn (3.4-14) will be,... 

For alkanes, the logarithm of viscosity has been correlated with atomic and with bond contributions to estimate tj at 0 and 20°C [13]. Considering a broader range of structural variety, neither the viscosity nor its logarithm is a constitutionally additive property. Application of the group contribution approach is based on additive parameters that allow viscosity estimations in combination with other experimental data such as density or vapor pressure. The viscosity-constitutional constant, /vc, is such an additive parameter ... 

There is a wide-spread literature on methods for temperature-dependent viscosity estimation. Their discussion and further references can be found elsewhere [1,2,17,18,19,20,21], Usually, these methods are based on various input data, such as density, boiling point, and critical point. Dynamic viscosities of most gases increase with increasing temperature. Dynamic viscosities of most liquids, including water, decrease rapidly with increasing temperature [18]. 

Before each viscosity measurement, temperature and salinity of the water sample were simultaneously measured using a Hydrolab probe, and did not exhibit any significant difference with the theoretical viscosity estimated from temperature and salinity (Wilco-xon-Mann-Whitney f/-test, P > 0.05). This ensures the relevance of our rjTS estimates. Between each viscosity measurement, the viscometer chamber was carefully rinsed first with deionised water and then with bulk-phase seawater filtered through 0.2 pm pore size filters to avoid any potential dilution of the next sample. 

The strain-rate estimates suggest that the microstructures were formed by flow in the mantle related to large-scale tectonic processes. In the case of the Voltri peridotites, Drury et al. (1990) have related this deformation to extension and rifting of a continental lithospheric plate. The high-temperature deformation occurred under asthenospheric conditions, whereas the low-temperature deformation occurred within the lithosphere. The estimates of upper mantle viscosity obtained from the study of microstructures are lower than those for average viscosity obtained independently from other methods, such as analysis of glacial rebound of land surfaces (Nakada and Lambeck 1987), which are also based on a number of assumptions. All the samples studied are derived from the uppermost part of the mantle, so the viscosity estimates obtained from the microstructural study are consistent with the presence of a low viscosity zone between the... 

As discussed in the Introduction, considerable effort has been devoted to the study of transport properties. Specifically, viscosity estimates are of potential importance in the rational design of lubricants. In these simulations, two main approaches have been used. The earlier of the two focused on a linear response theory based Green-Kubo formula ... 

The uncertainties of the equation of state are approximately 0.2% (to 0.5% at high pressures) in density, 1% (in the vapor phase) to 2% in heat capacity, 1% (in the vapor phase) to 2% in the speed of sound, and 0.2% in vapor pressure, except in the critical region. For viscosity, estimated uncertainty is 2%. For thermal conductivity, estimated uncertainty, except near the critical region, is 4-6%. 

Gardas RL, Coutinho JAP (2008) A group contribution method for viscosity estimation of ionic liquids. Fluid Phase Equilib 266 195-201... 

Poly(decamethylene adipate) obtained in Exercise 5.4 was subjected to alcoholysis with 5% of its own weight of (a) ethylene glycol and (b) n-octyl alcohol in the presence of p-toluene sulfonic acid catalyst till there was no further change in viscosity. Estimate the limiting Xn of the mixture. Assume equal reactivity of functional groups. 

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