Viscosity correlations for minor constituent fluids in natural gas: n-octane, n-nonane and n-decane

Viscosities of Liquid Cyclohexane and Decane at Temperatures between (303 and 598) K and Pressures up to 4 MPa Measured in a Dual-Capillary Viscometer

“…From these deviations, we can also conclude that the experimental data are internally consistent to within the estimate experimental uncertainty. Equation (16) Figure 7, we compare the new results with data from the literature [13][14][15][16][17][18][19] at pressures up to 10 MPa as deviations from the correlation of Tariq et al 1 Our results agree well with the majority of the experimental data reported in the literature; however, the data of Rajagapol et al 17 at temperatures below 400 K and those of Grachev et al 19 to constrain the behavior of their correlation in the liquid state at temperatures above 441 K and those data are systematically higher than ours at temperatures above 450 K. Figure 8 compares our new results with data from the literature 13,14,[20][21][22][23][24][25][26][27][28][29] at pressure up to 10 MPa as deviations from the correlation of Huber et al 2,3 At temperatures up to 500 K, our new data agree with the correlation to within about ±1 %, which is the stated uncertainty of the correlation for the saturated liquid. At higher temperatures, the deviations are somewhat dependent upon pressure and span the interval (-3 to -6) %.…”

“…In view of equation (2), the impedance ratio for T ≠ T0 can then be obtained by consideration of the integrated thermal expansions ΔL and Δr of the length and radius of the capillary leading, for a homogeneous material, to the following relation:…”

“…The corrected data were analyzed to obtain the relevant slope (dΔp/dQ), where Q was the volumetric flow rate at the pump, and the viscosity ratios were then evaluated from equation (12). The experimental viscosity ratios for cyclohexane and decane are given in Tables 2 and 3, together with absolute viscosities obtained using values of η(T0, p) from Tariq et al 1 for cyclohexane and from Huber et al 2,3 for decane.…”

“…The first term in square brackets in equation (15) (15) were estimated from the correlations of Tariq et al 1 for cyclohexane and Huber et al 2,3 for decane and it was found that the effects of the temperature and pressure uncertainties contributed less than 0.8 % to ur(rη). The standard relative uncertainties ur(rη) are shown in Figure 5 for both fluids.…”

“…Very few data were available for cyclohexane at higher temperatures and, amongst the primary data selected for the development of the correlation, only one data set for liquid cyclohexane extended to T > 441 K. The available viscosity data for decane have been reviewed and correlated by Huber et al 2 and their correlation is implemented in the REFPROP version 9.1 software package. 3 At temperatures up to about 400 K, multiple literature sources were in good agreement but at higher temperatures, especially above 450 K, very few data were available.…”