Page 323 - Process Modelling and Simulation With Finite Element Methods

3 10 Process Modelling and Simulation with Finite Element Methods

downwards. Hence, the shape of rising drop changes drastically. The lower drop
almost skids downward traveling drop and changes the contact point between the
interacting drops. Finally, coalescence takes place at 3.8 seconds.
Thus, it is found that the contact point of the interacting drops is very
significant in the coalescence phenomenon. Different types of contacting
schemes are observed for different approaches considered in the present set of
simulations merely by changing the initial condition.

8.5 Summary

The level set method is extensively used in the present simulations to study
computationally the coalescence of droplets in a two-phase system. FEMLAB
handles computationally intensive multi-phase modeling with ease using its
multiphysics utility that allows the coupling of different physics into one problem
as demonstrated here for the level-set method. In the present simulations, the
coalescence phenomenon has been extensively studied using various
configurations for the approach of drops. The curvature analysis performed
captures the rupture of the interface at the time of the coalescence.

Acknowledgements

We acknowledge Per-Olof Persson for use of his FEMLAB code which was
modified appropriately to treat coalescence. We thank Peter Norgaard for
helpful discussions.

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