Microscopic Investigation of Vortex Breakdown in a Dividing T-Junction Flow

TL;DR

This study uses 3D-printed microfluidic devices to visualize and analyze vortex breakdown in dividing T-junction flows, revealing how outflow imbalances influence vortex structures and providing a phase diagram for flow control.

Contribution

First visualization of vortex breakdown in T-junction microfluidic flows with controlled inflow and outflows, highlighting effects of outflow imbalance on vortex behavior.

Findings

Outflow imbalances significantly alter vortex structures.

A dimensionless phase diagram summarizes vortex breakdown regimes.

Controlled experiments decouple swirl effects from vorticity decay.

Abstract

3D-printed microfluidic devices offer new ways to study fluid dynamics. We present the first clear visualization of vortex breakdown in a dividing T-junction flow. By individual control of the inflow and two outflows, we decouple the effects of swirl and rate of vorticity decay. We show that even slight outflow imbalances can greatly alter the structure of vortex breakdown, by creating a net pressure difference across the junction. Our results are summarized in a dimensionless phase diagram, which will guide the use of vortex breakdown in T-junctions to achieve specific flow manipulation.