Tempered fractional LES modeling
نویسندگان
چکیده
The presence of nonlocal interactions and intermittent signals in the homogeneous isotropic turbulence grant multi-point statistical functions a key role formulating new generation large-eddy simulation (LES) models higher fidelity. We establish tempered fractional-order modeling framework for developing LES subgrid-scale models, starting from kinetic transport. employ L\'evy-stable distribution to represent source turbulent effects at level, we rigorously show that corresponding closure term emerges as fractional Laplacian, $(\Delta+\lambda)^{\alpha} (\cdot)$, $\alpha \in (0,1)$, \neq \frac{1}{2}$, $\lambda>0$ filtered Navier-Stokes equations. Moreover, prove frame invariant properties proposed model, complying with stresses. To characterize optimum values model parameters infer enhanced efficiency develop robust algorithm, involving two-point structure conventional correlation coefficients. In an priori study, evaluate capabilities developed fulfilling closed essential requirements, obtained weaker sense ideal (Meneveau 1994). Finally, undergoes posteriori analysis ensure numerical stability pragmatic model.
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ژورنال
عنوان ژورنال: Journal of Fluid Mechanics
سال: 2021
ISSN: ['0022-1120', '1469-7645']
DOI: https://doi.org/10.1017/jfm.2021.955