Tip streaming from drops flowing in a spiral microchannel

TL;DR

This study visualizes tip streaming phenomena in water drops transported by oil in a spiral microchannel, revealing how increasing shear causes drops to accelerate and develop singular tails, advancing understanding of microfluidic drop dynamics.

Contribution

It demonstrates the occurrence of tip streaming in a spiral microchannel, highlighting the effects of shear and elongation on drop acceleration and tail formation.

Findings

Tip streaming occurs as drops accelerate near the spiral center.

Drops develop singular tails indicating high shear effects.

Flow visualization confirms the influence of channel geometry on drop behavior.

Abstract

This fluid dynamics video shows drops of water being transported by a mean flow of oil, in a microchannel shaped as a logarithmic spiral. The channel shape means that the drops are submitted to an increasing shear and elongation as they flow nearer to the center of the spiral. A critical point is reached at which a long singular tail is observed behind the drops, indicating that the drops are accelerating. This is called "Tip streaming".