Enhancement of intermittency in superfluid turbulence.
نویسندگان
چکیده
We consider the intermittent behavior of superfluid turbulence in (4)He. Because of the similarity in the nonlinear structure of the two-fluid model of superfluidity and the Euler and Navier-Stokes equations, one expects the scaling exponents of the structure functions to be the same as in classical turbulence for temperatures close to the superfluid transition T(λ) and also for T << T(λ). This is not the case when the densities of normal and superfluid components are comparable to each other and mutual friction becomes important. Using shell model simulations, we propose that in this situation there exists a range of scales in which the effective exponents indicate stronger intermittency. We offer a bridge relation between these effective and the classical scaling exponents. Since this effect occurs at accessible temperatures and Reynolds numbers, we propose that experiments should be conducted to further assess the validity and implications of this prediction.
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عنوان ژورنال:
- Physical review letters
دوره 110 1 شماره
صفحات -
تاریخ انتشار 2013