Thermal effects on the lifetime of evaporating drops on fibers

TL;DR

This study investigates how thermal effects influence the evaporation lifetime of drops on fibers, combining experiments and a model that accounts for heat transfer and airflow, applicable in both quiescent and flowing air conditions.

Contribution

The paper introduces a comprehensive model that incorporates thermal effects into evaporation dynamics of drops on fibers, validated by experimental data in different airflow regimes.

Findings

Model accurately predicts droplet lifetime in diffusive regime

Thermal conductivity impacts evaporation rate

Flow conditions extend model applicability

Abstract

We present an experimental study on the evaporation of drops on fibers. More specifically, we focus on the droplet lifetime both in quiescent air and in an air flow of constant velocity. We propose a model to describe the evaporation rate and lifetime in a purely diffusive regime, which includes the liquid cooling associated with evaporation and the thermal conductivity of the atmosphere and the fiber. Our model effectively captures the primary physical behaviors, demonstrating a semi-quantiative agreement with our measurements across various liquids and fiber materials. Finally, the model is generalized to a convective air flow, which also rationalizes our experimental data.