5 papers
No new scaling laws of passive scalar with a constant mean gradient in decaying isotropic turbulence
Michael Frewer
In the study by Sadeghi & Oberlack [JFM 899, A10 (2020)] it is claimed that new scaling laws are derived for the case of passive scalar dynamics under the influence of a constant m…
Refuting the claim of conformal invariance for a zero-vorticity characteristic equation in 2D turbulence
Michael Frewer, George Khujadze
Although the current Reply by Grebenev et al. (2021a) makes their original analysis in Grebenev et al. (2017) more transparent, the actual problem remains. Their claim to have anal…
Conformal invariance and the Lundgren-Monin-Novikov equations for vorticity fields in 2D turbulence: Refuting a recent claim
Michael Frewer, George Khujadze
The recent claim by Grebenev et al. [J. Phys. A: Math. Theor. 50, 435502 (2017)] that the inviscid 2D Lundgren-Monin-Novikov (LMN) equations on a zero vorticity characteristic natu…
On physically redundant and irrelevant features when applying Lie-group symmetry analysis to hydrodynamic stability analysis
Michael Frewer
Every linear system of partial differential equations (PDEs) admits a scaling symmetry in its dependent variables. In conjunction with other admitted symmetries of linear type, the…
A note on the notion "statistical symmetry"
Michael Frewer, George Khujadze, Holger Foysi
A critical review is presented on the most recent attempt to generally explain the notion of "statistical symmetry". This particular explanation, however, is incomplete and misses…