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

Roman Cherniha

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arXiv · 2511.08656

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

Roman Cherniha

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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.

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Roman Cherniha. 2025-11-11. Comments on the paper `Modelling and nonclassical symmetry analysis of a complex porous media flow in a dilating channel'. https://arxiv.org/abs/2511.08656

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