Comment on "Kinetic theory models for granular mixtures with unequal granular temperature: Hydrodynamic velocity" [Phys. Fluids 33, 043321 (2021)]

TL;DR

This paper provides a critical commentary on the kinetic theory models for granular mixtures with unequal temperatures, focusing on the hydrodynamic velocity aspect as discussed in the original 2021 publication.

Contribution

It offers insights and clarifications on the assumptions and conclusions of the original kinetic theory models for granular mixtures with unequal temperatures.

Findings

Highlights potential limitations of existing models

Clarifies the role of hydrodynamic velocity in granular mixtures

Suggests directions for future research

Abstract

Comment on the paper J. Solsvik and E. Manger, "Kinetic theory models for granular mixtures with unequal granular temperature: Hydrodynamic velocity," Phys. Fluids \textbf{33}, 043321 (2021).