Calculation of the thermal conductivities of hydrogen, nitrogen, oxygen and carbon dioxide at high temperatures

Author(s):  
Anthony A. Clifford ◽  
Norman Platts
1960 ◽  
Vol 82 (1) ◽  
pp. 48-52 ◽  
Author(s):  
Robert G. Vines

Experimental results are reported for the thermal conductivities of air, argon, nitrogen, and carbon dioxide at temperatures up to 900 C, and of steam up to 560 C. These results are compared with values predicted from correlation formulas based on low temperature measurements.


2009 ◽  
Vol 24 (2) ◽  
pp. 430-435 ◽  
Author(s):  
D. Li ◽  
H.H. Hng ◽  
J. Ma ◽  
X.Y. Qin

The thermoelectric properties of Nb-doped Zn4Sb3 compounds, (Zn1–xNbx)4Sb3 (x = 0, 0.005, and 0.01), were investigated at temperatures ranging from 300 to 685 K. The results showed that by substituting Zn with Nb, the thermal conductivities of all the Nb-doped compounds were lower than that of the pristine β-Zn4Sb3. Among the compounds studied, the lightly substituted (Zn0.995Nb0.005)4Sb3 compound exhibited the best thermoelectric performance due to the improvement in both its electrical resistivity and thermal conductivity. Its figure of merit, ZT, was greater than the undoped Zn4Sb3 compound for the temperature range investigated. In particular, the ZT of (Zn0.995Nb0.005)4Sb3 reached a value of 1.1 at 680 K, which was 69% greater than that of the undoped Zn4Sb3 obtained in this study.


During the researches upon high-pressure explosions of carbonic oxide-air, hydrogen-air, etc., mixtures, which have been described in the previous papers of this series, a mass of data has been accumulated relating to the influence of density and temperature upon the internal energy of gases and the dissociation of steam and carbon dioxide. Some time ago, at Prof. Bone’s request, the author undertook a systematic survey of the data in question, and the present paper summarises some of the principal results thereof, which it is hoped will throw light upon problems interesting alike to chemists, physicists and internal-combustion engineers. The explosion method affords the only means known at present of determining the internal energies of gases at very high temperatures, and it has been used for this purpose for upwards of 50 years. Although by no means without difficulties, arising from uncertainties of some of the assumptions upon which it is based, yet, for want of a better, its results have been generally accepted as being at least provisionally valuable. Amongst the more recent investigations which have attracted attention in this connection should be mentioned those of Pier, Bjerrum, Siegel and Fenning, all of whom worked at low or medium pressures.


2021 ◽  
Author(s):  
Tomoki Kujirai ◽  
Akira Yamaguchi ◽  
Takeshi Fujita ◽  
Hideki Abe ◽  
Masahiro Miyauchi

Steam reforming of methane (SRM) requires high temperatures to be promoted, and the production of carbon dioxide from the side reaction has also become a problem. In this study, we...


Author(s):  
Theodore Hanein ◽  
Marco Simoni ◽  
Chun Long Woo ◽  
John L Provis ◽  
Hajime Kinoshita

The calcination of calcium carbonate (CaCO3) is a major contributor to carbon dioxide (CO2) emissions that are changing our climate. Moreover, the calcination process requires high temperatures (~900°C). A novel...


Measurements have been made by several observers on the thermal conductivities of metals and alloys up to high temperatures. Heat losses to the surroundings become large at high temperatures, hence the guard tube method, which to a great extent eliminates these losses, has been popular for work at these temperatures. This method was described and used by Berget in 1888, and later by Wilkes. These observers measured the rate of heat flow by a calorimetric method, which is not suitable for work at high temperatures. Honda and Simidu, using an internal heating coil, determined the heat flow from the energy input and were able to obtain results for nickel and steel to over 800°C. More recently, Schofield, using the guard tube method with an internal heating coil, has obtained results up to a maximum temperature of 700°C. with five metals. The present work was undertaken with a view to continuing the work of Professor C. H. Lees on the effect of temperatures between —160°C. and 15°C. on the thermal conductivities of nine metals and six alloys.


Nature ◽  
1974 ◽  
Vol 247 (5435) ◽  
pp. 67-67
Author(s):  
K. A. SOUZA ◽  
L. P. ZILL

Sign in / Sign up

Export Citation Format

Share Document