We present a stability result for stationary smooth helical ideal fluid flows by using the direct method of Liapunov. It is enunciated in terms of the norm \(L^{2}\) of the velocity and vorticity. A stability for monotonic helical vortices in the norm \(L^{1}\) is also obtained.

中文翻译：

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固定螺旋涡旋的非线性稳定性

通过使用Liapunov的直接方法，我们给出了平稳的平稳螺旋理想流体流动的稳定性结果。以速度和涡度的范数\（L ^ {2} \）来阐明。还获得了规范\（L ^ {1} \）中单调螺旋涡旋的稳定性。