The Temperature Dependence of the Thermal Conductivity of Air

Abstract

The thermal conductivity of air is determined in absolute measure between -183 and 218 �C. by the " thick-wire " variant of the " hot-wire " method. The apparatus consists of a platinum wire 11 6 cm. long and 1.5 mm. in diameter mounted in a 90 per cent. Pt 10 per cent. Ir tube of 7 mm. internal diameter. The temperature variation of the thermal conductivity of air can be represented with considerable accuracy by the quadratic formula ������������� kt=5. 75 x 10-5(l +0.00317t-0.0000021t2) The present paper suggests a value for the thermal conductivity of air at 0 �C. from a consideration of the data which have been obtained by various hot-wire methods.

Viscosity and Thermal Conductivity of Dry Air in the Gaseous Phase

“…(5) within ± 1 %. In the low-temperature region (up to 270 K), the data of Golubev (1963),Tl4 as well as of Taylor et al (1946) T6 and of Kannuluik et al (1951) at around room temperature, probably due to the incorrect correction for radiation heat loss in Taylor's study. Figure 12 shows deviations of some other data at atmospheric pressure.…”

“…Without further information, an evaluation of their data could not be done satisfactorily. Consequently, in the low-temperature region, the present authors included the data published before 1960 in the analysis and finally selected the data of Taylor and Johnston (1946)T6 and of Kannuluik and Carman (1951). T9 Although the data of Taylor et alT 6 are older, the experiments seem to be more reliable.…”

Wall-temperature effects on flame response to acoustic oscillations

“…It is then possible to find v, the true velocity over the wire, if ν and k are know as a function of the temperature. The viscosity can be found using the Sutherland law (Sutherland (1893)), and the thermal conductivity of the flow can be found using the correlation given by Kannuluik and Carman (1951). Figure. 1.11a, shows the effect of the flow temperature on the velocity measurements.…”

“…Table 1.2 summarizes the values of the coefficients used in the Sutherland law to calculate the viscosity. Likewise, k u is calculated with the correlations given by Kannuluik and Carman (1951) and Assael et al (1990) for air and methane respectively. Finally, the hot-wire correction that takes into account the changes in temperature and gas properties of the CH 4 -air mixture reads: Figure 1.11b shows the effect of the fuel mass fraction correction on the velocity measurements.…”

Measurement of the Thermal Conductivities of Gases at High Temperatures

“…From a smoothed curve relating the radiation losses with temperature, appropriate corrections could be made to each experimental measurement. 5 The temperature difference (AT) between emitter and receiver was usually between 5 and 10 C. The greatest accuracy was obtained when AT was large. Within experimental error, the results of the measurements at any temperature were independent of AT.…”