We investigate the stability of a fluid film with power-law rheology flowing down a porous nonplanar incline with periodic undulations. A model is implemented which accounts for filtration flow through the substrate. A reduction in dimensionality in the model is achieved by exploiting the assumed thinness of the liquid film relative to the wavelength of the bottom undulations. A steady flow is obtained and its linear stability determined through the application of Floquet–Bloch theory. A nonlinear stability analysis is also carried out by calculating the evolution of the perturbed steady flow by means of numerical simulations.
Instabilities of a shear-thinning fluid falling over an undulating porous layer / Pascal, J. -P.; Vacca, A.. - In: JOURNAL OF NON-NEWTONIAN FLUID MECHANICS. - ISSN 0377-0257. - 298:(2021), p. 104693. [10.1016/j.jnnfm.2021.104693]
Instabilities of a shear-thinning fluid falling over an undulating porous layer
Vacca A.
2021
Abstract
We investigate the stability of a fluid film with power-law rheology flowing down a porous nonplanar incline with periodic undulations. A model is implemented which accounts for filtration flow through the substrate. A reduction in dimensionality in the model is achieved by exploiting the assumed thinness of the liquid film relative to the wavelength of the bottom undulations. A steady flow is obtained and its linear stability determined through the application of Floquet–Bloch theory. A nonlinear stability analysis is also carried out by calculating the evolution of the perturbed steady flow by means of numerical simulations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
