Jet breakup dynamics of viscoelastic carboxymethyl cellulose solutions

TL;DR

This study experimentally explores how viscoelastic properties of CMC solutions influence jet breakup, droplet formation, and stability, revealing the roles of elasticity, flow conditions, and geometry in controlling jet dynamics.

Contribution

It provides new insights into the effects of viscoelasticity on jet breakup behavior, highlighting how CMC concentration and flow parameters modify stability and droplet formation.

Findings

Increased CMC concentration prolongs jet lifetime and alters pinch-off behavior.

Elasticity suppresses capillary instabilities, leading to beaded structures.

Jet length and droplet volume depend on flow rate, needle diameter, and viscoelastic effects.

Abstract

We experimentally investigate the breakup dynamics of viscoelastic jets composed of carboxymethyl cellulose (CMC) solutions, focusing on the dripping and Rayleigh regimes at low flow rates. By varying the CMC concentration, needle diameter ($D_n$), and flow rate ($Q$), we analyze the effects of elasticity, viscosity, and flow conditions on jet stability and droplet formation. Our results show that increasing CMC concentration enhances viscoelastic effects, leading to prolonged jet lifetimes, extended liquid threads, and modified pinch-off behavior. At higher concentrations, elasticity suppresses capillary-driven instabilities, slowing thinning and facilitating the formation of beaded structures. We observe that the interplay between inertial, capillary, and elastic forces, influenced by CMC concentration, governs the jet length, droplet volume, and breakup time, with needle diameter and flow rate playing a crucial role in jet breakup phenomenon.