Scale locality is a key concept in turbulent cascade theory and is also associated with reflection symmetry. Vortex stretching is proven to participate in the helicity cascade process while destroying the conservative characteristic of enstrophy transfer in three-dimensional flows. Numerical evidence indicates that a turbulent structure with scale L will also largely transfer its helicity to structures with scales of around 0.3L. However, the scale locality of the helicity cascade is slightly weaker than that of the energy cascade in physical space. The weaker scale locality suggests that more scales should be involved for turbulent modeling of helical turbulence.

中文翻译：

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物理空间中螺旋度级联的尺度局部性

尺度局部性是湍流级联理论中的关键概念，并且还与反射对称性相关。涡旋拉伸被证明参与了螺旋级联过程，同时破坏了三维流中涡旋传递的保守特性。数值证据表明，尺度为L的湍流结构也将很大程度上将其螺旋度转移到尺度为0.3 L的结构上。但是，螺旋级联的尺度局部性比物理空间中能量级联的尺度局部性稍弱。较弱的比例局部性表明，应为螺旋湍流的湍流建模涉及更多比例。