Microgravity Science and Technology

, Volume 31, Issue 5, pp 487–503 | Cite as

Collision Behavior of Heterogeneous Liquid Droplets

  • N. E. Shlegel
  • P. A. StrizhakEmail author
  • R. S. Volkov
Original Article
Part of the following topical collections:
  1. Thirty Years of Microgravity Research - A Topical Collection Dedicated to J. C. Legros


Processes involved in the collision of liquid droplets enhance their atomization. If droplets contain more than one component, these processes become especially strong and intense. In this paper, we describe experiments for heterogeneous droplets of water solutions, emulsions, and slurries typical of fuel, firefighting, and heat and mass transfer technologies. We determine the conditions for a stable occurrence of the four droplet collision regimes: bounce, coalescence, separation, and disruption. We go on to establish how droplet dimensions, velocities, impact angles, component concentrations, as well as liquid viscosity, surface tension, and density affect collision parameters. The experimental results are generalized using collision regime maps produced in the coordinate systems controlling for the variations of Weber, Reynolds, Ohnesorge, and capillary numbers, as well as angular and linear interaction parameters. The results are compared with the scarce data by other authors. The Weber number variation range is not the only factor influencing the droplet collision behavior the form of four interaction regimes. Viscosity and surface tension of the liquid have a significant impact as well. An increase in the viscous forces can provide conditions for droplet breakup into a maximum number of small fragments. Coalescence is the dominating mode at low viscosity and high surface tension. Droplet bounce occurrence does not only depend on the Weber number range but also on phase transformations and thermophysical properties of the liquid. Finally, we determine the droplets interaction parameters for group of liquids that can provide intense droplet atomization through collisions.

Graphical Abstract

Interaction regime maps for heterogeneous liquid droplets


Solutions, emulsions, slurries Droplets Collisions Bounce Coalescence Separation Disruption 

Nomenclature and Units


Distance between droplets’ centers of mass, mm


Dimensionless linear interaction parameter


Capillary number


Number of the detected post-collision droplets (child-droplets)


Common number of child-droplets


Ohnesorge number

P1, P2, P3

Relative frequency of occurrence of coalescence, separation and disruption

Rd1, Rd2

Radii of the first and second droplets, mm


Radii of the distributions of post-collision liquid fragments, mm


Reynolds number


Total area of pre-collision droplets, m2


Total area of post-collision droplets, m2


Time, ms


Temperature, °C

Ud1, Ud2

Velocities of the first and second droplets, m/s


Velocity scale used for dimensionless processing of experimental results, 1 m/s


Gases velocity, m/s


Relative velocity of droplets, m/s


Total volume of pre-collision droplets, m3


Total volume of post-collision droplets, m3


Weber number

Greek Symbols


Impact angle, °


Dimensionless angular interaction parameter


Dimensionless angular interaction parameter, which is calculated by an impact angle according to Krishnan and Loth 2015


A parameter to numerically determine the conditions of droplet entrainment by gases


Impact angle (according to Krishnan and Loth 2015), °


Dynamic viscosity, Pa∙s


Density, kg/m3


Surface tension, N/m



The research was supported by the Russian Science Foundation (project 18–71–10002). The members of Heat Mass Transfer Simulation Lab ( of National Research Tomsk Polytechnic University are grateful to our colleague Professor J.C. Legros for his ideas and contribution to the development of the Lab’s research areas.


  1. Antonov, D.V., Volkov, R.S., Kuznetsov, G.V., Strizhak, P.A.: Experimental study of the effects of collision of water droplets in a flow of high-temperature gases. J. Eng. Phys. Thermophys. 89, 100–111 (2016)Google Scholar
  2. Antonov, D., Bellettre, J., Tarlet, D., Massoli, P., Vysokomornaya, O., Piskunov, M.: Impact of holder materials on the heating and explosive breakup of two-component droplets. Energies. 11, (2018). Google Scholar
  3. Antonov, D.V., Vysokomornaya, O.V., Piskunov, M.V., Fedorenko, R.M., Yan, W.M.: Influence of solid nontransparent inclusion shape on the breakup time of heterogeneous water drops. Int. Commun. Heat Mass Transfer. 101, 21–25 (2019)Google Scholar
  4. Arkhipov, V.A., Ratanov, G.S., Trofimov, V.F.: Experimental investigation of the interaction of colliding droplets. J. Appl. Mech. Tech. Phys. 19, 201–204 (1978)Google Scholar
  5. Arkhipov, V.A., Vasenin, I.M., Trofimov, V.F.: Stability of colliding drops of ideal liquid. J. Appl. Mech. Tech. Phys. 24, 371–373 (1983)Google Scholar
  6. Arogeti, M., Sher, D., Sher, E.: Drop impact on a small target with an inclined plane. Exp. Thermal Fluid Sci. 99, 140–148 (2018)Google Scholar
  7. Barai, N., Mandal, N.: Breakup versus coalescence of closely packed fluid drops in simple shear flows. Int. J. Multiphase Flow. 111, 1–15 (2019)MathSciNetGoogle Scholar
  8. Brandenbourger, M., Caps, H., Vitry, Y., Dorbolo, S.: Electrically charged droplets in microgravity: impact and trajectories. Microgravity Sci. Technol. 29, 229–239 (2017)Google Scholar
  9. Breitenbach, J., Kissing, J., Roisman, I.V., Tropea, C.: Characterization of secondary droplets during thermal atomization regime. Exp. Thermal Fluid Sci. 98, 516–522 (2018)Google Scholar
  10. Charalampous, G., Hardalupas, Y.: Collisions of droplets on spherical particles. Phys. Fluids. 29, 103305 (2017). CrossRefGoogle Scholar
  11. Chen, S., Bartello, P., Yau, M.K., Vaillancourt, P.A., Zwijsen, K.: Cloud droplet collisions in turbulent environment: collision statistics and parameterization. J. Atmos. Sci. 73, 621–636 (2016)Google Scholar
  12. Finotello, G., De, S., Vrouwenvelder, J.C.R., Padding, J.T., Buist, K.A., Jongsma, A., Innings, F., Kuipers, J.A.M.: Experimental investigation of non-Newtonian droplet collisions: the role of extensional viscosity. Exp. Fluids. 59, (2018a).
  13. Finotello, G., Kooiman, R.F., Padding, J.T., Buist, K.A., Jongsma, A., Innings, F., Kuipers, J.A.M.: The dynamics of milk droplet–droplet collisions. Exp. Fluids. 59, (2018b).
  14. Focke, C., Kuschel, M., Sommerfeld, M., Bothe, D.: Collision between high and low viscosity droplets: direct numerical simulations and experiments. Int. J. Multiphase Flow. 56, 81–92 (2013)Google Scholar
  15. Ghorbani, M., Alcan, G., Sadaghiani, A.K., Mohammadi, A., Unel, M., Gozuacik, D., Koşar, A.: Characterization and pressure drop correlation for sprays under the effect of micro scale cavitation. Exp. Thermal Fluid Sci. 91, 89–102 (2018)Google Scholar
  16. Hu, C., Xia, S., Li, C., Wu, G.: Three-dimensional numerical investigation and modeling of binary alumina droplet collisions. Int. J. Heat Mass Transf. 113, 569–588 (2017)Google Scholar
  17. Kan, H., Nakamura, H., Watano, S.: Effect of collision angle on particle-particle adhesion of colliding particles through liquid droplet. Adv. Powder Technol. 29, 1317–1322 (2018)Google Scholar
  18. Kim, W.S., Lee, S.Y.: Behavior of a water drop impinging on heated porous surfaces. Exp. Thermal Fluid Sci. 55, 62–70 (2014)Google Scholar
  19. Krishnan, K.G., Loth, E.: Effects of gas and droplet characteristics on drop-drop collision outcome regimes. Int. J. Multiphase Flow. 77, 171–186 (2015)MathSciNetGoogle Scholar
  20. Kuan, C.-K., Pan, K.-L., Shyy, W.: Study on high-weber-number droplet collision by a parallel, adaptive interface-tracking method. J. Fluid Mech. 759, 104–133 (2014)MathSciNetGoogle Scholar
  21. Kuznetsov, G.V., Piskunov, M.V., Volkov, R.S., Strizhak, P.A.: Unsteady temperature fields of evaporating water droplets exposed to conductive, convective and radiative heating. Appl. Therm. Eng. 131, 340–355 (2018)Google Scholar
  22. Legros, J.C., Piskunov, M.V., Lutoshkina, O.S.: Vaporization of water droplets with non-metallic inclusions of different sizes in a high-temperature gas. Int. J. Therm. Sci. 127, 360–372 (2018a)Google Scholar
  23. Legros, J.C., Piskunov, M.V., Lutoshkina, O.S., Voytkov, I.S.: Water drops with graphite particles triggering the explosive liquid breakup. Exp. Thermal Fluid Sci. 96, 154–161 (2018b)Google Scholar
  24. Li, J.: Macroscopic model for head-on binary droplet collisions in a gaseous medium. Phys. Rev. Lett. 117, (2016).
  25. Li, S., Zhang, Y., Qi, W., Xu, B.: Quantitative observation on characteristics and breakup of single superheated droplet. Exp. Thermal Fluid Sci. 80, 305–312 (2017)Google Scholar
  26. Liang, G., Guo, Y., Mu, X., Shen, S.: Experimental investigation of a drop impacting on wetted spheres. Exp. Thermal Fluid Sci. 55, 150–157 (2014)Google Scholar
  27. Liu, M., Bothe, D.: Numerical study of head-on droplet collisions at high weber numbers. J. Fluid Mech. 789, 785–805 (2016)Google Scholar
  28. Misyura, S.Y.: The effect of weber number, droplet sizes and wall roughness on crisis of droplet boiling. Exp. Thermal Fluid Sci. 84, 190–198 (2017)Google Scholar
  29. Moqaddam, A.M., Chikatamarla, S.S., Karlin, I.V.: Simulation of binary droplet collisions with the entropic lattice Boltzmann method. Phys. Fluids. 28, 022106 (2016). CrossRefGoogle Scholar
  30. Orme, M.: Experiments on droplet collisions, bounce, coalescence and disruption. Prog. Energy Combust. Sci. 23, 65–79 (1997)Google Scholar
  31. Pawar, S.K., Henrikson, F., Finotello, G., Padding, J.T., Deen, N.G., Jongsma, A., Innings, F., Kuipers, J.A.M.H.: An experimental study of droplet-particle collisions. Powder Technol. 300, 157–163 (2016)Google Scholar
  32. Pazhi, D.G., Galustov, V.S.: Basics of Liquid Spraying. Chemistry, Moscow (1984)Google Scholar
  33. Piskunov, M.V., Legros, J.C.: Evaporation of water droplets with metallic inclusions. Int. J. Multiphase Flow. 102, 64–76 (2018)Google Scholar
  34. Sazhin, S.S.: Modelling of fuel droplet heating and evaporation: recent results and unsolved problems. Fuel. 196, 69–101 (2017)Google Scholar
  35. Sazhin, S.S., Rybdylova, O., Crua, C., Heikal, M., Ismael, M.A., Nissar, Z., Aziz, A.R.B.A.: A simple model for puffing/micro-explosions in water-fuel emulsion droplets. Int. J. Heat Mass Transf. 131, 815–821 (2019)Google Scholar
  36. Sechenyh, V.V., Legros, J.-C., Shevtsova, V.: Optical properties of binary and ternary liquid mixtures containing tetralin, isobutylbenzene and dodecane. J. Chem. Thermodyn. 62, 64–68 (2013)Google Scholar
  37. Shraiber, A.A., Podvysotsky, A.M., Dubrovsky, V.V.: Deformation and breakup of drops by aerodynamic forces. Atomization Sprays. 6, 667–692 (1996)Google Scholar
  38. Simanovskii, I.B., Viviani, A., Dubois, F., Legros, J.C.: Nonlinear buoyant-thermocapillary waves in two-layer systems with an interfacial heat release. Microgravity Sci. Technol. 27, 11–26 (2014)Google Scholar
  39. Sprittles, J.E., Shikhmurzaev, Y.D.: Coalescence of liquid drops: different models versus experiment. Phys. Fluids. 24, 122105 (2012). CrossRefzbMATHGoogle Scholar
  40. Suzuki, Y., Harada, T., Watanabe, H., Shoji, M., Matsushita, Y., Aoki, H., Miura, T.: Visualization of aggregation process of dispersed water droplets and the effect of aggregation on secondary atomization of emulsified fuel droplets. Proc. Combust. Inst. 33, 2063–2070 (2011)Google Scholar
  41. Szakáll, M., Urbich, I.: Wind tunnel study on the size distribution of droplets after collision induced breakup of levitating water drops. Atmos. Res. 213, 51–56 (2018)Google Scholar
  42. Tang, C., Qin, M., Weng, X., Zhang, X., Zhang, P., Li, J., Huang, Z.: Dynamics of droplet impact on solid surface with different roughness. Int. J. Multiphase Flow. 96, 56–69 (2017)Google Scholar
  43. Tarlet, D., Josset, C., Bellettre, J.: Comparison between unique and coalesced water drops in micro-explosions scanned by differential calorimetry. Int. J. Heat Mass Transf. 95, 689–692 (2016)Google Scholar
  44. Totani, T., Kodama, T., Watanabe, K., Nagata, H., Kudo, I.: Experimental study on convergence of droplet streams under microgravity. Microgravity Sci. Technol. 17, 31–38 (2005)Google Scholar
  45. Volkov, R.S., Strizhak, P.A.: Research of temperature fields and convection velocities in evaporating water droplets using planar laser-induced fluorescence and particle image velocimetry. Exp. Thermal Fluid Sci. 97, 392–407 (2018)Google Scholar
  46. Volkov, R.S., Kuznetsov, G.V., Strizhak, P.A.: Statistical analysis of consequences of collisions between two water droplets upon their motion in a high-temperature gas flow. Tech. Phys. Lett. 41, 840–843 (2015)Google Scholar
  47. Xie, H., Zeng, Z., Zhang, L., Yokota, Y., Kawazoe, Y., Yoshikawa, A.: Simulation on thermocapillary-driven drop coalescence by hybrid lattice boltzmann method. Microgravity Sci. Technol. 28(66–77), 67–77 (2016)Google Scholar
  48. Zaripov, T.S., Rybdylova, O., Sazhin, S.S.: A model for heating and evaporation of a droplet cloud and its implementation into ANSYS fluent. Int. Commun. Heat Mass Transfer. 97, 85–91 (2018)Google Scholar
  49. Zhang, H., Li, Y., Li, J., Liu, Q.: Study on separation abilities of moisture separators based on droplet collision models. Nucl. Eng. Des. 325, 135–148 (2017)Google Scholar

Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.National Research Tomsk Polytechnic UniversityTomskRussia

Personalised recommendations