Numerical and experimental investigation of the axis-switching behavior of a rectangular jet

• Published in: International journal of multiphase flow 2024-11, Vol.180, p.104951, Article 104951
• Main Authors: García Llamas, C., Swami, V.V., Petrova, V.P., Buist, K.A., Kuipers, J.A.M., Baltussen, M.W.
• Format: Article
• Language: English
• Subjects: Axis-switching; Local Front Reconstruction Method; Numerical simulation; Rectangular jet
• ISSN: 0301-9322
• DOI: 10.1016/j.ijmultiphaseflow.2024.104951

Rectangular jets exhibit axis-switching behavior which results in enhanced flow entrainment compared to round jets. This feature allows for their potential industrial use as passive flow controllers in mixing applications. However, rectangular jets have received limited attention compared to round jets. To operate rectangular jets optimally, a better understanding on the underlying phenomena influencing the axis-switching of the jet is required. In this paper, Direct Numerical Simulations of rectangular jets are performed at different injection velocities using the Local Front Reconstruction Method (LFRM) to track the liquid–gas interface. The simulations are validated using experiments in a similar range of Weber and Reynolds numbers. The obtained results showed that LFRM can accurately capture the jet oscillations, break-up lengths and droplet sizes observed experimentally. Additionally, a fully developed velocity profile at the nozzle outlet enhances the jet stability resulting in larger break-up length values compared to a uniform velocity profile. [Display omitted] •Rectangular jets are simulated using LFRM to track the liquid-gas interface•Break-up length, droplet sizes, and oscillating wavelength were investigated•The study demonstrates a good agreement between experiments and simulations•Different velocity profiles at the nozzle outlet are investigated.•Fully developed flow leads to more stable jets, resulting in larger break-up lengths•Axis-switching and flow entrainment phenomena are observed for both velocity profiles•Time-coherent azimuthal and stream-wise vortices are identified.