Linear instability of power-law liquid jets with heat and mass transfer in a swirling gas

This study investigates the instability and breakup mechanism of power-law liquid jets subject to heat and mass transfer and swirling gas in a confined environment. A mathematical model is established, and the dispersion relation between the dimensionless instability growth rate and the dimensionless wavenumber is derived by linear instability analysis. The results show that swirling gas enhances jet instability by amplifying azimuthal velocity and promoting Kelvin–Helmholtz instability. It can divide the jet into multiple species. Heat and mass transfer effect varies with the Weber number, suppressing instability at low values and enhancing it at high values. Additionally, as the heat and mass transfer increases, the jet develops toward a large azimuthal wavenumber. It is obtained through sensitivity analysis that increasing the gas velocity and wall constrains can effectively promote the jet instability. Finally, it is concluded that shear-thickening fluids are more prone to destabilization due to the dominant effect of swirling gas.