为揭示气液螺旋环状流界面波失稳机理，基于经典的Kelvin-Helmholtz不稳定性理论，利用双流体模型，建立螺旋涡流作用下界面波的动力学模型。通过求解界面波色散方程，给出界面失稳的准则并进行理论验证。研究表明，界面波的增长特性决定于气动力、离心力和表面张力的相互作用。其中，不同气液动压相对大小条件下，离心力对界面波稳定性存在三重影响。基于此准则条件，系统分析气流速度、旋流强度及管径对界面波增长特性的影响规律。
To reveal the mechanism of interfacial wave instability in swirling annular gas-liquid flow, a theoretical model for interfacial waves is established based on the Kelvin-Helmholtz instability theory and the two-fluid model. The dispersion equation is derived, and the interfacial stability criterion is obtained and verified analytically. Results indicate that the interplay of aerodynamic, centrifugal, and surface tension forces gives rise to interfacial instability. Specially, the centrifugal force acting on the interface has triple effects on the stability, depending on the relative magnitudes of gas/liquid dynamic pressures. Effects of gas velocity, swirl intensity, and cylinder curvature on the growth characteristics of the interfacial waves are examined in detail.
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