“…This is in agreement with findings for noble gases and is probably due to a temperature measurement error in the experimental equipment of Kestin and co-workers extensively discussed by Vogel et al 30 Furthermore, it is to consider that Smith and co-workers [15][16][17][18] directed their measurements to the ranges of very high and low temperatures connected with uncertainties of about ( 0.5 % at the temperatures under discussion. Hence, it can be concluded that the most reliable data 19,[23][24][25]28 including those of the present paper even agree within ( (0.1 to 0.2) % between room temperature and 420 K. The difference between the basis correlation of Lemmon and Jacobsen and the most reliable data is probably caused by that Lemmon and Jacobsen do not critically evaluate the uncertainties of the measured data, which are included in the development of their correlation.…”
Section: Comparison With Literaturementioning
confidence: 49%
“…Experimental data: ⊙, Clarke and Smith; ⊡, Dawe and Smith; ⊞, Gough et al; ⊗, Matthews et al; ★, Hoogland et al; #, Kestin et al; <, Kestin et al; >, Kestin et al. ; +, Timrot et al; ▿, Vogel; □, Vogel et al; ◇, Docter et al; , ▵, Evers et al; ×, Hurly et al; ○, present work. 4 Comparison of the experimental viscosity data of the present paper at different temperatures with the viscosity surface correlation of Lemmon and Jacobsen . Deviations [Δ = 100(η exp − η cor )/η cor ] as a function of molar density (ρ).…”
Section: Discussionmentioning
confidence: 82%
“…Experimental data: ⊙, Clarke and Smith; ⊡, Dawe and Smith; ⊞, Gough et al; ⊗, Matthews et al; ★, Hoogland et al; #, Kestin et al; <, Kestin et al; >, Kestin et al. ; +, Timrot et al; ▿, Vogel; □, Vogel et al; ◇, Docter et al; , ▵, Evers et al; ×, Hurly et al; ○, present work.…”
Section: Discussionmentioning
confidence: 82%
“…This needs a critical judgment of the techniques and the associated theories applied for the measurements as well as a mutual comparison of the high-quality data. Thus the most reliable data 19,[23][24][25]28 including those of the present paper demonstrate that an improved correlation could be characterized in the dilute-gas region by uncertainties of ( (0.1 to 0.2) % between room temperature and 420 K, possibly even up to 650 K. The comparison with experimental data, measured by Kestin et al, 14,31,32 Timrot et al, 23 Hoogland et al, 19 Hurly et al, 29 Flynn et al, 38 Gracki et al, 39 and Evers et al, 28 and the critical…”
Section: Discussionmentioning
confidence: 99%
“…Smith and co-workers − used capillary viscometers for relative measurements, whereas Hoogland et al applied an absolute one. Kestin et al, − Timrot et al, and Vogel and his collaborators , used oscillating-disk viscometers in a relative manner. Docter et al , and Evers et al developed a newly designed rotating-cylinder viscometer combined with a densimeter for absolute measurements.…”
The viscosity coefficient of gaseous nitrogen was measured with a vibrating-wire viscometer of very high precision. The measurements were performed along the six isotherms of (298.15, 323.15, 348.15, 373.15, 398.15, and 423.15) K and at pressures up to a maximum of 35 MPa. The gas densities needed for the evaluation of the measuring values were calculated using an equation of state by Span et al. (J.
“…This is in agreement with findings for noble gases and is probably due to a temperature measurement error in the experimental equipment of Kestin and co-workers extensively discussed by Vogel et al 30 Furthermore, it is to consider that Smith and co-workers [15][16][17][18] directed their measurements to the ranges of very high and low temperatures connected with uncertainties of about ( 0.5 % at the temperatures under discussion. Hence, it can be concluded that the most reliable data 19,[23][24][25]28 including those of the present paper even agree within ( (0.1 to 0.2) % between room temperature and 420 K. The difference between the basis correlation of Lemmon and Jacobsen and the most reliable data is probably caused by that Lemmon and Jacobsen do not critically evaluate the uncertainties of the measured data, which are included in the development of their correlation.…”
Section: Comparison With Literaturementioning
confidence: 49%
“…Experimental data: ⊙, Clarke and Smith; ⊡, Dawe and Smith; ⊞, Gough et al; ⊗, Matthews et al; ★, Hoogland et al; #, Kestin et al; <, Kestin et al; >, Kestin et al. ; +, Timrot et al; ▿, Vogel; □, Vogel et al; ◇, Docter et al; , ▵, Evers et al; ×, Hurly et al; ○, present work. 4 Comparison of the experimental viscosity data of the present paper at different temperatures with the viscosity surface correlation of Lemmon and Jacobsen . Deviations [Δ = 100(η exp − η cor )/η cor ] as a function of molar density (ρ).…”
Section: Discussionmentioning
confidence: 82%
“…Experimental data: ⊙, Clarke and Smith; ⊡, Dawe and Smith; ⊞, Gough et al; ⊗, Matthews et al; ★, Hoogland et al; #, Kestin et al; <, Kestin et al; >, Kestin et al. ; +, Timrot et al; ▿, Vogel; □, Vogel et al; ◇, Docter et al; , ▵, Evers et al; ×, Hurly et al; ○, present work.…”
Section: Discussionmentioning
confidence: 82%
“…This needs a critical judgment of the techniques and the associated theories applied for the measurements as well as a mutual comparison of the high-quality data. Thus the most reliable data 19,[23][24][25]28 including those of the present paper demonstrate that an improved correlation could be characterized in the dilute-gas region by uncertainties of ( (0.1 to 0.2) % between room temperature and 420 K, possibly even up to 650 K. The comparison with experimental data, measured by Kestin et al, 14,31,32 Timrot et al, 23 Hoogland et al, 19 Hurly et al, 29 Flynn et al, 38 Gracki et al, 39 and Evers et al, 28 and the critical…”
Section: Discussionmentioning
confidence: 99%
“…Smith and co-workers − used capillary viscometers for relative measurements, whereas Hoogland et al applied an absolute one. Kestin et al, − Timrot et al, and Vogel and his collaborators , used oscillating-disk viscometers in a relative manner. Docter et al , and Evers et al developed a newly designed rotating-cylinder viscometer combined with a densimeter for absolute measurements.…”
The viscosity coefficient of gaseous nitrogen was measured with a vibrating-wire viscometer of very high precision. The measurements were performed along the six isotherms of (298.15, 323.15, 348.15, 373.15, 398.15, and 423.15) K and at pressures up to a maximum of 35 MPa. The gas densities needed for the evaluation of the measuring values were calculated using an equation of state by Span et al. (J.
SummaryAfter describing simplified equations expressing the temperature dependency of the viscosity of carrier gases (helium, nitrogen and hydrogen) relative to a base value, absolute relationships based on the kinetic theory of gases are discussed. Comparative data obtained using various calculation methods are given and are compared to measured values. Based on the kinetic relationships, simplified equations are suggested to describe the temperature relationship of viscosity. Finally, the influence of pressure on the viscosity is also briefly discussed. As a supplement, viscosity data are tabulated for the three gases in the range of 0 "C to 400 "C in increments of 2 K , calculated using the kinetic relationships.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations –citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
