Comments on the paper `Modelling and nonclassical symmetry analysis of a complex porous media flow in a dilating channel'

TL;DR

This paper critiques a recent study on modeling complex porous media flow, arguing that its symmetry analysis results are incomplete and potentially misleading, thereby questioning the validity of its theoretical conclusions.

Contribution

It provides a critical review showing that the previous symmetry analysis was incomplete and misleading, highlighting the need for more rigorous methods.

Findings

The original symmetry analysis was found to be incomplete.

The original results were shown to be potentially misleading.

The critique emphasizes the importance of thorough symmetry analysis.

Abstract

The Comments are devoted to the recently published paper 'Modelling and nonclassical symmetry analysis of a complex porous media flow in a dilating channel' (Physica D. 481 (2025) 134834), in which a model describing an unsteady two-dimensional viscous incompressible fluid flow through a porous medium is studied. The main theoretical results of that study consists of finding Lie and nonclassical symmetries of a fourth-order PDE, which was derived by simplification of the given model. Here it is shown that the main theoretical results derived therein are incomplete and misleading.