Intermittency in the joint cascade of energy and helicity.
نویسندگان
چکیده
The statistics of the energy and helicity fluxes in isotropic turbulence are studied using high resolution direct numerical simulation. The scaling exponents of the energy flux agree with those of the transverse velocity structure functions through refined similarity hypothesis, consistent with Kraichnan's prediction. The helicity flux is even more intermittent than the energy flux. Consistent with this observation, the spatial helicity-flux structures are finer than those of energy flux and more tubelike in geometry.
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ورودعنوان ژورنال:
- Physical review letters
دوره 90 21 شماره
صفحات -
تاریخ انتشار 2003