The evolution characteristics of the droplets colliding with the wet wall surfaces are essential to the performance of the steam-water separator in the nuclear power plant. When the droplets impact the liquid film with different velocities, the diverse phenomena will occur. The collision characteristics of droplets with the wall surface during the movement are experimentally studied. In the experiment the high-speed camera with a shooting speed of 2000 frames per second is used to obtain the spread process of droplets hitting the liquid film vertically at different velocities. The phenomena of the crown with and without splashing are analyzed. The critical parameters of phenomena are recorded, and the qualitative conditions generated by the three phenomena are analyzed. The critical velocity to generate the secondary droplet is 0.021 m/s and the critical velocity to generate the main droplet is 0.017 m/s when a droplet with a diameter of 3.62 mm hits the liquid film. If the kinetic energy of falling droplets can be reduced, the waste caused by the Worthington jet and splashing droplets can be effectively reduced. The present study can lay basis for the design of the steam-water separator and the space droplet radiator.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Cossali, G. E., Coghe, A., Marengo, M. 1997. The impact of a single drop on a wetted solid surface. Exp Fluids, 22: 463–472.
Kong, Q., Ji, X., You, T., Zhou, R., Xu, J. 2020. Dynamic characteristics of droplet collision on the hydrophilic-hydrophobic interface. Atomic Energy Science and Technology, 10: 1801–1808.
Levin, Z., Hobbs, P. V. 1971. Splashing of water drops on solid and wetted surfaces: Hydrodynamics and charge separation. Philosophical Transactions of the Royal Society of London Series A, Mathematical and Physical Sciences, 269: 555–585.
Li, D., Qiu, X., Zheng, Z., Cui, Y., Ma, P. 2015. Numerical analysis of droplets impacting different wetting walls. Transactions of the Chinese Society of Agricultural Machinery, 46: 294–302.
Li, J., Huang, S., Wang, X. 2007. Experimental research of separation efficiency on steam-water separator with corrugated plates. Nuclear Power Engineering, 28: 94–97.
Liang, C. 2013. Numerical study on dynamic characteristics of small droplets hitting solid wall and thin liquid film. Chongqing University.
Liu, D. 2015. Simulation of droplet impact on superhydrophobic wall. Beijing Jiaotong University.
Loth, E. 2000. Numerical approaches for motion of dispersed particles, droplets and bubbles. Prog Energ Combust, 26: 161–223.
Marengo, M., Antonini, C., Roisman, I. V., Tropea, C. 2011. Drop collisions with simple and complex surfaces. Curr Opin Colloid In, 16: 292–302.
Ogawa, A., Utsuno, K., Mutou, M., Kouzen, S., Shimotake, Y., Satou, Y. 2006. Morphological study of cavity and worthington jet formations for Newtonian and non-Newtonian liquids. Particulate Sci Technol, 24: 181–225.
Roisman, I. V., Horvat, K., Tropea, C. 2006. Spray impact: Rim transverse instability initiating fingering and splash, and description of a secondary spray. Phys Fluids, 18: 102104.
Totani, T., Itami, M., Nagata, H., Kudo, I., Iwasaki, A., Hosokawa, S. 2002. Performance of droplet generator and droplet collector in liquid droplet radiator under microgravity. Microgravity Sci Tech, 13: 42–45.
Totani, T., Kodama, T., Nagata, H., Kudo, I. 2005. Thermal design of liquid droplet radiator for space solar-power system. J Spacecraft Rockets, 42: 493–499.
Totani, T., Kodama, T., Watanabe, K., Nanbu, K., Nagata, H., Kudo, I. 2006. Numerical and experimental studies on circulation of working fluid in liquid droplet radiator. Acta Astronaut, 59: 192–199.
Wei, D., Zhang, R., Wu, R., Zhou, H. 2004. Design of piezoelectric droplet ejection device. Journal of Tsinghua University (Science and Technology), 44: 1107–1110.
Xue, G., He, Y., Fu, J., Wu, S. 2014. Droplet ejection behavior of piezoelectric nozzle and its influencing factors. Optics and Precision Engineering, 22: 2166–2172.
Yamamoto, K., Motosuke, M., Ogata, S. 2018. Initiation of the Worthington jet on the droplet impact. Appl Phys Lett, 112: 093701.
Zhang, F. 2018. Research on droplet extinction model. Tsinghua University.
Zhang, L. 2016. Numerical simulation of the motion characteristics of droplets hitting a hydrophobic/superhydrophobic surface. Lubrication and Sealing, 9: 63–68.
Zhao, F., Zhao, C., Bo, H. 2018. Numerical investigation of the separation performance of full-scale AP1000 steam-water separator. Ann Nucl Energy, 111: 204–223.
Zhou, S., Huan, J. Design of piezoelectric droplet ejection device. 1999. Journal of Sichuan Union University, 3: 65–67.
Zhu, J., Wu, Z., Ye, S., Bai, J., Guan, X., Wang, Q., Wu, H. 2014. Research on droplet movement and distribution characteristics in spray tower. Chemical and Pharmaceutical Engineering, 35: 11–15.
This work is financially supported by China Postdoctoral Science Foundation (2019M650064P, 2019T120256), Science and Technology on Reactor System Design Technology Laboratory (HT-KFKT-09-2018004), National Key R&D Program of China (2017YFE0106200), Natural Science Foundation of Heilongjiang Province (JQ2019A001), Postdoctoral Science Foundation of Heilongiang Province (LBM-Z19013), and Fundamental Research Funds for the Central Universities (3072020CFT1504).
About this article
Cite this article
Ju, W., Wu, Y., Lin, S. et al. Visual experimental study of droplet impinging on liquid film and analysis of droplet evolution characteristics. Exp. Comput. Multiph. Flow (2020). https://doi.org/10.1007/s42757-020-0081-3
- droplet collision
- secondary droplet
- liquid film
- steam-water separator