Droplet mobilization in actuated deformable tubes

TL;DR

This paper investigates how different actuation methods in deformable tubes influence oil droplet mobilization, revealing distinct effects of frequency and amplitude on transport efficiency through simulations.

Contribution

It introduces a detailed fluid-structure interaction simulation approach to compare hydrodynamic and wall actuation effects on droplet mobilization in deformable tubes.

Findings

Hydrodynamic actuation increases mobilization time with frequency.

Wall actuation shows a resonance effect near the tube's natural frequency.

Higher actuation amplitude decreases mobilization time in hydrodynamic case.

Abstract

We study the mobilization of an oil droplet in a deformable, actuated constricted tube subjected to two different actuation mechanisms: hydrodynamic actuation (oscillatory body force in the fluid) and dynamic wall actuation (oscillatory traction on the tube walls). Using high-resolution fluid-structure interaction simulations, we analyze the effects of actuation frequency and amplitude on droplet transport through the constriction. Our simulations show that hydrodynamic actuation leads to a monotonic increase in the droplet's mobilization time with increasing actuation frequency, and a decrease with increasing actuation amplitude. In contrast, dynamic wall actuation exhibits a resonance effect-the mobilization time reaches a minimum at a frequency near the tube's resonant frequency. Our study highlights the potential of actuation mechanisms in deformable tubes for precise control of droplet transport in bio-microfluidic applications.