Intermittency of turbulent velocity and scalar fields using three-dimensional local averaging
نویسندگان
چکیده
An efficient approach for extracting 3D local averages in spherical subdomains is proposed and applied to study the intermittency of small-scale velocity scalar fields direct numerical simulations isotropic turbulence. We focus on inertial-range scaling exponents locally averaged energy dissipation rate, enstrophy rate corresponding mixing a passive $\theta$ presence uniform mean gradient. The Taylor-scale Reynolds number $R_\lambda$ goes up $1300$, Schmidt $Sc$ $512$ (albeit at smaller $R_\lambda$). exponent $\mu \approx 0.23$, whereas that slightly larger; trends with suggest this will be case even extremely large $R_\lambda$. $\mu_\theta 0.35$ $Sc=1$. These findings are essential agreement previously reported results literature. further show $\mu_\theta$ decreases monotonically increasing $Sc$, either as $1/\log Sc$ or weak power law, suggesting \to 0$ $Sc \infty$, reaffirming recent breakdown anomaly limit.
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ژورنال
عنوان ژورنال: Physical review fluids
سال: 2022
ISSN: ['2469-9918', '2469-990X']
DOI: https://doi.org/10.1103/physrevfluids.7.l072601