Microfluidics and Nanofluidics

, Volume 16, Issue 1–2, pp 329–346 | Cite as

Numerical simulation of the collision of two microdroplets with a pseudopotential multiple-relaxation-time lattice Boltzmann model

  • Ernesto Monaco
  • Gunther Brenner
  • Kai H. Luo
Research Paper


Collisions of two equally sized liquid microdroplets in gaseous phase are numerically studied by the lattice Boltzmann method (LBM). The multiphase formulation adopted is a pseudopotential model with improved treatment of the equation of state and force incorporation which is then coupled with the multiple-relaxation-time scheme. That allows a detailed investigation into microdroplet collisions characterized by high-density ratios as well as by relevant inertial effects. Simulations related to a wide range of flow parameters (e.g. Weber and Reynolds numbers) are reported, in order to embrace all the collisional regimes presented in previous experimental studies. From surface tension-driven coalescence (both inertial and viscous coalescence have been examined) to catastrophic break-up with the formation of children microdroplets, the simulations demonstrate that the LBM correctly reproduces the collision dynamics and the final outcomes in almost all the regimes. Different break-up mechanisms like end-pinching and capillary wave-induced break-up have been observed. Finally, the initial stages of the inertia-dominated head-on collision process have been studied, showing once more the effectiveness and reliability of this multiphase LBM implementation.


Microdroplet collision Microflows Lattice Boltzmann 



Partial support from the UK EPSRC under the Grant No. EP/J016381 is gratefully acknowledged; the authors also acknowledge the HLRN (High Performance Computing Network of Northern Germany) in Hannover for the kind support and for making the computational facilities available. The results reported in this study were obtained by using a modified version of the DL_MESO_LBE package ( the authors acknowledge M. Seaton for providing the original version of the code.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Institute for Applied MechanicsTechnical UniversityClausthal-ZellerfeldGermany
  2. 2.Energy Technology Research Group, Faculty of Engineering and the EnvironmentSouthampton UniversitySouthamptonUK

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