# Dynamics of thin liquid films on vertical cylindrical fibers

## TL;DR

This paper develops an advanced lubrication model to analyze the complex dynamics of thin liquid films flowing down vertical fibers, incorporating slip, nonlinear curvature, and stabilization effects, to explain experimental observations.

## Contribution

It introduces a comprehensive lubrication model with novel physical effects to better understand thin film flow dynamics on fibers, including droplet stability and transitions.

## Key findings

- Identification of a stable liquid layer influencing flow stability
- Model successfully explains droplet velocity and transition behaviors
- Stability analysis supports experimental observations

## Abstract

Recent experiments of thin films flowing down a vertical fiber with varying nozzle diameters present a wealth of new dynamics that illustrate the need for more advanced theory. We present a detailed analysis using a full lubrication model that includes slip boundary conditions, nonlinear curvature terms, and a film stabilization term. This study brings to focus the presence of a stable liquid layer playing an important role in the full dynamics. We propose a combination of these physical effects to explain the observed velocity and stability of traveling droplets in the experiments and their transition to isolated droplets. This is also supported by stability analysis of the traveling wave solution of the model.