Iranian Journal of Mechanical Engineering Transactions of ISME

Iranian Journal of Mechanical Engineering Transactions of ISME

Droplet formation in microchannel under influence of electric field using the Boltzmann lattice method

Authors
Mohammad Eftekhari Yazdi 1
Armen Adamian 2
1 Assistant professor, Islamic Azad University, Central Tehran Branch
2 Assistant professor, Department of Mechanical Engineering, Islamic Azad University, Central Tehran Branch
Abstract
The phenomena of formation and detachment of droplets are one of fundamental issues in
studying two-phase flows and have been seen in lots of natural phenomenon and processes,
such as spraying processes, ink jet printing, emulsion, etc. Between different numerical
methods, the lattice Boltzmann method (LBM) has been developed in to an alternative and
promising numerical scheme for simulating multi-component fluid flows. In this project,
formation and detachment of droplets were simulated, using LBM and particularly index
function model. Results were validated using two-phase flows methods. After code validation,
the formation and detachment of droplets in a cross-junction micro channel and under the
electric field effects were studied. To survey different effects on this phenomenon,
dimensionless numbers were studied.
Finally, the effect of variation of permittivity, conductivity and capillary number for droplets
were studied under different situations. Results show that the electric force have a positive
effect in expedition of droplet formation, and also index function model proved its very useful
abilities. We have smaller drops with high frequency which shows that we can control the
droplet formation.
Keywords
Droplet formation
Boltzmann method
Electric field
Michrochanel

Subjects

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Iranian Journal of Mechanical Engineering Transactions of ISME
Volume 18, Issue 2 - Serial Number 43
Fluid Mechanics and Heat Transfer
Autumn 2016
Pages 42-63

  • Receive Date 27 September 2015
  • Revise Date 30 November 2016
  • Accept Date 30 November 2016