Page 285 - Bird R.B. Transport phenomena

§9.1 Fourier's Law of Heat Conduction (Molecular Energy Transport) 269

Table 9.1-1 Summary of Units for Quantities in Eqs. 9.1-2 and 9

SI c.g.s. British
W/m 2 cal/cm 2 • s Btu/hr • ft 2
T К С F
У m cm ft
к W/m-К cal/cm • s • С Btu/hr • ft • F
с, J/K-kg cal/C-g Btu/F • lb flI
2
2
2
a m /s cm /s ft /s
Pa-s g/cm • s lb /ft-hr
m
Pr — — —
Note: The watt (W) is the same as J/s, the joule (J) is the same as N • m,
2
the newton (N) is kg • m/s , and the Pascal (Pa) is N/m . For more
2
information on interconversion of units, see Appendix F.
ductivity of gases, liquids, liquid metals, and solids are given in Tables 9.1-2, 9.1-3,
9.1-4, and 9.1-5. In making calculations, experimental values should be used when
possible. In the absence of experimental data, one can make estimates by using the
methods outlined in the next several sections or by consulting various engineering
handbooks. 7

Table 9.1-2 Thermal Conductivities, Heat Capacities, and Prandtl Numbers of Some
Common Gases at 1 atm Pressure" 7
Temperature Thermal conductivity Heat capacity Prandtl number
Gas ПК) к (W/m • K) C,(J/kg-K) Pr(—)
H 2 100 0.06799 11,192 0.682
200 0.1282 13,667 0.724
300 0.1779 14,316 0.720
o 2 100 0.00904 910 0.764
200 0.01833 911 0.734
300 0.02657 920 0.716
NO 200 0.01778 1015 0.781
300 0.02590 997 0.742
CO 200 0.00950 734 0.783
2
300 0.01665 846 0.758
CH 100 0.01063 2073 0.741
4
200 0.02184 2087 0.721
300 0.03427 2227 0.701

" Taken from J. O. Hirschfelder, C. F. Curtiss, and R. B. Bird, Molecular Theory of Gases and Liquids, Wiley,
New York, 2nd corrected printing (1964), Table 8.4-10. The к values are measured, the C values are
p
calculated from spectroscopic data, and /x is calculated from Eq. 1.4-18. The values of C for H represent
p
2
a 3:1 ortho-para mixture.

For example, W. M. Rohsenow, J. P. Hartnett, and Y. I. Cho, eds., Handbook of Heat Transfer,
7
McGraw-Hill, New York (1998); Landolt-Bornstein, Zahlenwerte und Funktionen, Vol. II, 5, Springer
(1968-1969).