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An Experimental Investigation on the Coalescent Behaviors of Colliding Droplets

Published online by Cambridge University Press:  05 May 2011

C. H. Wang ,
K. L. Pan ,
S. Y. Fu ,
W. C. Huang  and
J. Y. Yang
C. H. Wang*
Affiliation:
Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan 10617, R.O.C.
K. L. Pan*
Affiliation:
Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan 10617, R.O.C.
S. Y. Fu*
Affiliation:
Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan 10617, R.O.C.
W. C. Huang*
Affiliation:
Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan 10617, R.O.C.
J. Y. Yang*
Affiliation:
Institute of Applied Mechanics, National Taiwan University, Taipei, Taiwan 10617, R.O.C.
*
*Professor
*Professor
**Graduate student
**Graduate student
*Professor
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Abstract

The coalescent behaviors in collisions between two droplets respectively made of different alkanes, water and alkane, methanol and alkane, and ethanol and hexadecane were experimentally studied. The coalescent results between two droplets of different alkanes are qualitatively the same as that with the same material, which simply form a spherical droplet. However, it took time to have the concentration within the droplet to become uniformly distributed. The collision results of water and alkane droplets collision become slightly more complex, in most cases, the water droplet was either inserted into or adhesive to the hexadecane droplet while only insertion was observed if the target droplet was dodecane or heptane. The inserted water droplet tends to partially expose to the environment as the volume fraction of water is sufficiently high, say, ∼0.62 for hexadecane, > 0.70 for dodecane, and > 0.78 for heptane; and the limit is lowered with the decreasing of water or merged droplet size. For the cases of methanol and alkanes, and ethanol and hexadecane, the two colliding droplets were adhesive to each other in all the studies. Furthermore, in most conditions, air bubbles were observed immediately after the collisions, while only few or even none of them might be trapped within the final merged droplet.

Keywords

Droplet collisionInsertive coalescenceAdhesive coalescence.
Type
Articles
Information
Journal of Mechanics , Volume 23 , Issue 4 , December 2007 , pp. 415 - 422
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2007

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References

1.Law, C. K., Prog. Energy Combustion Science, 8, p. 169 (1982).CrossRefGoogle Scholar
2.Law, C. K. and Law, H. K., Modern Developments in Energy, Combustion, and Spectroscopy, F.A., Williams, A.K., Oppenheim, D.B., Olfe, and M., Lapp, Ed., Pergamon Press, p. 29 (1993).CrossRefGoogle Scholar
3.Lasheras, J. C., Fernandez-Pello, A. C. and Dryer, F. L., Combust. Sci. Tech., 22, p. 195 (1980).CrossRefGoogle Scholar
4.Sangiovanni, J. J. and Kesten, A. S., Combust. Sci. Tech., 16, p. 59 (1977).CrossRefGoogle Scholar
5.Wang, C. H., Liu, X. Q. and Law, C. K., Combust. Flame, 56, p. 175 (1984).CrossRefGoogle Scholar
6.Wang, C. H., Shy, K. H. and Lieu, L. C., Combust. Sci. Tech., 118, p. 63(1996).CrossRefGoogle Scholar
7.Wang, C. H. and Liou, D. S., J. Chinese Soc. of M.E. 17–4, p. 387 (1996).Google Scholar
8.Hopkinson, B. P., I. M. E. Proceedings, p. 679 (1913).Google Scholar
9.Greeves, G., Khan, I. M. and Onion, G., 16th International Symposium on Combustion, p. 321 (1976).Google Scholar
10.Cornet, I. and Nero, W. E., Industry and Engineering Chemistry, 2133 (1955).Google Scholar
11.Wang, C. H. and Ni, L. H., The Chinese J. Mechanics, 12–4, p. 465 (1996).Google Scholar
12.Ivanov, V. M. and Nefedov, P. I., NASA Tech. Translation TTF-258 (1965).Google Scholar
13.Lasheras, J. C., Fernandez-Pello, A. C. and Dryer, F. L., Combust. Sci. Tech., 21, p. 1 (1979).CrossRefGoogle Scholar
14.Wang, C. H. and Law, C. K., Combust. Flame, 59, p. 53 (1985).CrossRefGoogle Scholar
15.Wang, C. H. and Chen, J. T., Int. Comm. Heat Mass Transfer, 23, p. 823 (1996).CrossRefGoogle Scholar
16.Ashgriz, N. and Givi, P., Int. J. Heat Fluid Flow, 8–3, p. 205(1987).CrossRefGoogle Scholar
17.Ashgriz, N. and Poo, J. Y., J. Fluid Mech., 221, p. 183 (1990).CrossRefGoogle Scholar
18.Jiang, Y. J., Umemura, A. and Law, C. K., J. Fluid Mech., 234, p. 171 (1992).CrossRefGoogle Scholar
19.Wang, C. H., Hung, W. G., Fu, S. Y., Huang, W. C. and Law, C. K., Combust. Flame, 114, p. 280 (2003).Google Scholar
20.Wang, C. H., Lin, C. Z., Hung, W. G., Huang, W. C. and Law, C. K., Combust. Sci. Tech., 176, p. 71 (2004).CrossRefGoogle Scholar
21.Wang, C. H., Fu, S. Y., Kung, L. J. and Law, C. K., Proceedings of the Combustion Institute, 30, p. 1965 (2005).CrossRefGoogle Scholar