However, for the para-varicose disturbance, the gas rotation plays a negative role on instability of symmetric mode, while it plays a strong positive role on instability of asymmetric mode.

• 对于对称模式；气体旋转运动是低阶模式扰动的促稳因素；然而却是高阶模式扰动的强烈的失稳因素.