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Showing posts from June, 2022

Statistically invariant eddy viscosity models

Published in  Physics of Fluids, 2022  by Klingenberg & Oberlack. This publication is seriously misleading. All details are given in Appendix A in  https://arxiv.org/abs/2008.08580 , and more comprehensively in  https://doi.org/10.5281/zenodo.4275736 .

On the Lie symmetries of characteristic function hierarchy in compressible turbulence

Published in European Journal of Applied Mathematics, 2022  by Praturi, Plümacher & Oberlack. All problems that one encounters in the incompressible case translate here one-to-one to the compressible case: A symmetry analysis of an unclosed system with an infinite hierarchy is performed again, leading to two nonphysical "symmetries" (4.17) and (4.18), where the latter one is incorrectly elevated again to a symmetry that should reflect external intermittency in turbulent flows. But, exactly as in the incompressible case, these two "symmetries" are just mathematical artefacts of the unclosed equations and not reflected by experiment or numerical simulation. They both fail to model turbulence or to derive turbulent scaling laws that can be matched to relevant data. The scaling failure in the incompressible case is explicitly shown in https://doi.org/10.1017/jfm.2019.985 ,  https://arxiv.org/abs/1412.3061 ,  https://arxiv.org/abs/1606.08396 ,  https://doi....

Turbulence statistics of arbitrary moments of wall-bounded shear flows: A symmetry approach

Published in Physical Review Letters, 2022  by Oberlack, Hoyas, Kraheberger, Alcantara-Avila & Laux. This study is seriously misleading. All details given in https://arxiv.org/abs/2202.04635 . 

Conformal invariance of the 1-point statistics of the zero-isolines of 2d scalar fields in inverse turbulent cascades

Published in Physical Review Fluids, 2021  by Waclawczyk, Grebenev & Oberlack. This study is seriously misleading and flawed. Details and corrections are given in https://arxiv.org/abs/2111.02822   and more comprehensively in  https://doi.org/10.5281/zenodo.6228153 .

New scaling laws for turbulent Poiseuille flow with wall transpiration – CORRIGENDUM

Published in JFM, 2021 by Avsarkisov, Oberlack & Hoyas. Although this publication is already a Corrigendum, it is still seriously in error.  All details given in Appendix D in  https://arxiv.org/abs/2202.04635 .

New symmetry-induced scaling laws of passive scalar transport in turbulent plane jets

Published in JFM, 2021 by Sadeghi, Oberlack & Gauding. This publication is seriously misleading. Details are given in  https://arxiv.org/abs/2202.04635, and https://doi.org/10.5281/zenodo.4570586 .

Reply to Conformal invariance of the zero-vorticity Lagrangian path in 2D turbulence

Published in Journal of Physics A, 2021 by Grebenev, Waclawczyk & Oberlack. This publication is seriously misleading and flawed. All details and corrections are given in  https://arxiv.org/abs/2110.11057, and more comprehensively in  https://doi.org/10.5281/zenodo.6228153 .

Reply to Conformal invariance of the Lundgren-Monin-Novikov equations for vorticity fields in 2D turbulence

Published in Journal of Physics A, 2021 by Grebenev, Waclawczyk & Oberlack. This publication is seriously misleading and flawed. All details and corrections are given in  https://arxiv.org/abs/2110.11057, and more comprehensively in  https://doi.org/10.5281/zenodo.6228153 .  

New scaling laws of passive scalar with a constant mean gradient in decaying isotropic turbulence

Published in JFM, 2020 by Sadeghi & Oberlack. The "new scaling laws" claimed in this study are not new. They already were derived and discussed in http://arks.princeton.edu/ark:/88435/dsp015t34sm99d . For more details see https://arxiv.org/abs/2205.15652 .

Conformal invariance of characteristic lines in a class of hydrodynamic models

Published in Symmetry, 2020 by Waclawczyk, Grebenev & Oberlack. This publication is seriously misleading and flawed. For details and corrections also to the subsequent article that appeared in Phys.Rev.Fluids (2021) ,  see https://arxiv.org/abs/2111.02822 and https://doi.org/10.5281/zenodo.6228153 .