that
u s = surface velocity, one-dimensional, mm/s (parallel to
Lee then derived eq D12a by substitution of eq D23 and D25 into eq D21. It is also of some interest to note that the curvature c is given by d0/ds.
belt) u , = belt velocity, mm/s u s = surface velocity, two-dimensional, mm/s, eq 10 x = vertical coordinate upward from bath, meniscus height, mm X = meniscus height, nondimensional, n/a y = horizontal coordinate, distance from belt, mm
Nomenclature a = capillary length of liquid, (2u/pg)'/*, mm A = parameter, Appendix B B 1 = upper profile intercept, nondimensional, eq 7 B 2 = lower profile intercept, nondimensional, eq 6 c = curvature of meniscus, eq 13, mm-l C = curvature of meniscus, nondimensional, eq 2 Ca = capillary number, u,(p/u), nondimensional F , = stretch term, nondimensional, eq 23 g = acceleration of gravity h = meniscus thickness a t any point, mm h , = characteristic thickness, (pu,/pg)1/2,mm ho = film thickness, constant thickness region, mm H = meniscus thickness, nondimensional, h/a L = meniscus thickness, nondimensional, h/ho L' = dL/dX (Also L" and L"' are used for higher derivatives) M1 = slope of upper profile, nondimensional, eq 7 M 2 = slope of lower profile, nondimensional, eq 6 p = pressure in liquid phase po = pressure in gas phase Re = Reynolds number, hcu,p/p s = the length along the interface, mm T o = film thickness, nondimensional, ho(pg/puw,)1/2 or ho h c
Greek Letters liquid viscosity, N-s/m? liquid density, kg/m" X = meniscus height, nondimensional, x/ho u = surface tension of the liquid-air interface, N/km
p = p =
Literature Cited Batchelor. G. K.. "An Introduction to Fluid Dynamics," ChaDter 3, Cambridae University Press, 1962. Ernrnons, H W., "Fundamentals of G a s Dynamics," pp 57, 62, Princeton University Press, Princeton, N.J., 1958. Lee, C. Y., "Meniscus Flow Fields", Ph.D. Dissertation, Drexel University, Philadelphia, Pa., 1974. Lee, C. Y., Braccilli, J. J., Tallrnadge, J. A., Annual AlChE Meeting, New York. N.Y., 1972. Lee, C. Y., Tallmadge, J. A . , 46th National Colloid Symposium, ACS, Amherst, Mass., 1972. Lee, C. Y., Tallrnadge, J. A., AiChEJ., 19, 403 (1973a). Lee, C. Y., Tallrnadge, J. A,, AlChEJ., 19, 865 (1973b). Lee, C. Y., Tallmadge. J. A., AiChEJ., 20, 1079 (1974a). Lee, C. Y., Tallrnadge, J. A., h d . Eng. Chem., Fundam., 13, 356 (1974b). Lee, C. Y., Tallrnadge, J. A., ind. Eng. Chem., Fundam., 14, 120 (1975). Scriven, L. E., Chem. Eng. Sci., 12, 98 (1960). Spiers. R. P.. Subbaraman. C. V.. Wilkinson, W. L., Chem. Eng. Sci., 29, 389 ( 1974).
Receiced for reuieu September 2 5 , 1975 Accepted June 7,1976
Decomposition of Carbon Dioxide in an Induction-Coupled Argon Plasma Jet Yukio Nishimura" and Takeyoshi Takenouchi Research Institute of industrial Science, Kyushu University, Fukuoka 8 12, Japan
The decomposition of C 0 2 was studied in an induction-coupledargon plasma jet at 1 atm in order to obtain information on high-temperature reactions. The major products were CO and 02.As the inside diameter of the probe which was used to quench the decomposed products decreased, the mole fractions of CO and 02 in the quenched gas increased, whereas the gas temperature at the probe inlet was constant within the limits of experimental error. An increase in the flow rate of argon also increased the mole fractions of CO and O2 in the quenched gas. The product distribution was different when a CO-O2 mixture (molar ratio of C 0 : 0 2 = 2:l)was used instead of C02 as the feed.
Introduction In hot or arc plasma chemistry, the quenching rate of hot gas streams has an important influence on the distribution of the final products. One of the techniques used to quench reacting high-temperature gas streams is placing them in contact with a cold wall by, for example, passing them through a small-diameter, water-cooled tube. Baddour and Iwasyk (1962) have studied the reactions of elemental carbon with hydrogen above 2800 K, using this quenching method. A similar method of quenching has been also applied to the synthesis of nitrogen fluorides (Bronfin and Hazlett, 1966), to that of hydrogen cyanide (Bronfin, 1969), and to the decomposition of CO (Nishimura et al., 1974). 266
Ind. Eng. Chem., Fundam., Vol. 15, No. 4, 1976
The purpose of this work was to obtain information on the high-temperature reactions in the carbon-oxygen system in the plasma jet and on these reactions during very rapid cooling.
Experimental Section Materials. Argon used in this work was high-purity (>99.99%) cylinder gas which contained N2 (
