@Article{AAMM-16-1,
author = {Qilong, Guo and Pengxin, Liu and Li, Chen and Sun, Dong and Yuan, Xianxu},
title = {On the Characteristic Length Scale for the Synthetic Turbulence Based on the Spalart-Allmaras Model},
journal = {Advances in Applied Mathematics and Mechanics},
year = {2024},
volume = {16},
number = {1},
pages = {122--145},
abstract = {<p style="text-align: justify;">In the hybrid RANS-LES simulations, proper turbulent fluctuations should
be added at the RANS-to-LES interface to drive the numerical solution restoring to
a physically resolved turbulence as rapidly as possible. Such turbulence generation
methods mostly need to know the distribution of the characteristic length scale of the
background RANS model, which is important for the recovery process. The approximation of the length scale for the Spalart-Allmaras (S-A) model is not a trivial issue
since the model’s one-equation nature. As a direct analogy, the approximations could
be obtained from the definition of the Prandtl’s mixing length. Moreover, this paper
proposes a new algebraic expression to approximate the intrinsic length scale of the
S-A model. The underlying transportation mechanism of S-A model are largely exploited in the derivation of this new expression. The new proposed expression is employed in the generation of synthetic turbulence to perform the hybrid RANS-LES simulation of canonical wall-bounded turbulent flows. The comparisons demonstrated
the feasibility and improved performance of the new length scale on generating synthetic turbulence at the LES inlet.</p>},
issn = {2075-1354},
doi = {https://doi.org/10.4208/aamm.OA-2021-0298},
url = {https://global-sci.com/article/72803/on-the-characteristic-length-scale-for-the-synthetic-turbulence-based-on-the-spalart-allmaras-model}
}