In this study, the instability behavior of a confined non-Newtonian liquid jet in an annular gas layer is investigated theoretically. The viscosity of the non-Newtonian liquid is described using the power law model, and the corresponding dispersion relation is obtained by conducting a linear stability analysis. Additionally, the effects of heat and mass transfer, gas-to-liquid axial velocity ratio, power law index, and gas layer thickness on the instability of the power law liquid jet are investigated. The results demonstrate that the heat and mass transfer at the liquid–gas interface destabilizes the power law liquid jet flow. The results also indicate that an increase in the thickness of the gas layer makes the confined power law liquid jet unstable. Furthermore, the confined shear-thickening liquid jet is the most difficult to breakup in comparison with the shear-thinning and Newtonian liquid jets.

在这项研究中，从理论上研究了在环形气体层中受限的非牛顿液体射流的不稳定性行为。使用幂律模型描述非牛顿液体的粘度，并通过进行线性稳定性分析获得相应的色散关系。此外，研究了传热传质，气液轴向速度比，幂律指数和气体层厚度对幂律液体射流不稳定性的影响。结果表明，液-气界面处的传热和传质使幂律液体射流不稳定。结果还表明，气体层厚度的增加使得受限幂律液体射流不稳定。此外，