Viscous influences on impulsively generated focused jets

Cheng, Xianggang and Chen, Xiao-Peng and Ding, Hang and Zhang, Chun-Yu and Hu, Haibao and Jia, Laibing (2024) Viscous influences on impulsively generated focused jets. Physical Review Fluids, 9 (8). L082001. ISSN 2469-990X (https://doi.org/10.1103/PhysRevFluids.9.L082001)

[thumbnail of Cheng-etal-PRF-2024-Viscous-influences-on-impulsively-generated-focused-jets]
Preview
Text. Filename: Cheng-etal-PRF-2024-Viscous-influences-on-impulsively-generated-focused-jets.pdf
Final Published Version
License: Creative Commons Attribution 4.0 logo

Download (1MB)| Preview

Abstract

Impulsively generated focused jets play a significant role in various applications, including inkjet printing, needle-free drug delivery, and microfluidic devices. As the demand for generating jets and droplets from medium to highly viscous liquids increases, understanding the role of viscosity in jetting dynamics becomes crucial. While previous studies have examined the viscous effects on walls, the impact on free surfaces has not been thoroughly understood. This study aims to bridge this gap by integrating experiments with numerical simulations to investigate the viscous effects on focused jet formation. We demonstrate that mass and momentum transfer along the tangential direction of the free surface contribute to focused jet formation, and viscosity plays a key role in this transfer process. The viscosity-induced diffusion of the shear flow and vorticity near the free surface reduces the jet speed. Based on experimental observations and simulation results, we propose an equation to predict the viscous jet velocity. These findings offer new perspectives on viscous interface dynamics in advanced manufacturing and biomedical applications.

ORCID iDs

Cheng, Xianggang, Chen, Xiao-Peng, Ding, Hang, Zhang, Chun-Yu, Hu, Haibao and Jia, Laibing ORCID logoORCID: https://orcid.org/0000-0003-1327-5516;