In this paper, instabilities and breakup phenomena of a viscous liquid column jet in an inviscid stationary surrounding gas are analytically investigated, when the jet flows through a coaxial cylindrical sheath. Under a long wave approximation, axisymmetric non-linear evolution equations of the jet and surrounding gas are derived and numerically solved under a spatially periodic boundary condition. Validity and limitation of the approximation are examined in the linear regime in comparison with exact three-dimensional instabilities. It is shown in the non-linear analysis that there exist three types of breakup modes: the Rayleigh mode in which the surface tension instability is dominant and the breakup is caused by pinching, the first wind-induced mode in which blobs connected by threads are produced by increased aerodynamic instability and the second wind-induced mode in which the jet surface deforms to be spiked like a cusp without pinching and droplets are to be produced from...

中文翻译：

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流过同轴圆柱护套的周围气体中液柱射流的不稳定性

本文分析了粘性液体柱射流在不粘稠的固定周围气体中的不稳定性和破裂现象，当该射流流过同轴的圆柱形鞘管时。在长波近似下，推导了射流和周围气体的轴对称非线性演化方程，并在空间周期性边界条件下进行了数值求解。与精确的三维不稳定性相比，在线性方案中检验了逼近的有效性和局限性。非线性分析表明，存在三种类型的破坏模式：瑞利模式，其中表面张力不稳定性占主导地位，并且破坏是由于挤压引起的，