**ABSTRACT**

Drop formation in cross-junction micochannels is numerically studied using the lattice Boltzmann method with pseudo-potential model. To verify the simulation, the results are compared to previous numerical and experimental data. Furthermore, the effects of capillary number, flow rate ratio, contact angle and viscosity ratio on the flow patterns, drop length and interval between drops are investigated and highlighted. The results show that the drop forming process has different regimes, namely, jetting, drop and squeezing regimes. Also, it is shown that increasing in the flow rate ratio in the squeezing regime causes increment in drop length and decrement in drops interval distance. On the other hand, the drops length and the interval between the generated drops increase as contact angle increases. Also, the drop length and distance between drops is solely affected by viscosity ratio.

**KEYWORDS**

PAPER SUBMITTED: 2016-03-22

PAPER REVISED: 2016-08-30

PAPER ACCEPTED: 2016-09-02

PUBLISHED ONLINE: 2016-10-01

**THERMAL SCIENCE** YEAR

**2018**, VOLUME

**22**, ISSUE

**2**, PAGES [909 - 919]

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