Spatiotemporal instability of a confined capillary jet

TL;DR

This paper provides a comprehensive analytical, numerical, and experimental study of the spatiotemporal instability in confined capillary jets, extending previous models to include inertial effects and validating predictions with experiments.

Contribution

It introduces an extended analytic model for low Reynolds flows and a numerical scheme for higher inertial regimes, improving prediction accuracy of jet stability.

Findings

Analytical model accurately predicts instability thresholds.

Numerical scheme captures inertial effects in jet behavior.

Experimental results validate theoretical predictions.

Abstract

Recent experimental studies on the instability appearance of capillary jets have revealed the capabilities of linear spatiotemporal instability analysis to predict the parametrical map where steady jetting or dripping takes place. In this work, we present an extensive analytical, numerical and experimental analysis of confined capillary jets extending previous studies. We propose an extended, accurate analytic model in the limit of low Reynolds flows, and introduce a numerical scheme to predict the system response when the liquid inertia is not negligible. Theoretical predictions show a remarkable accuracy with results from the extensive experimental exploration provided.