Onset of synchronous and asynchronous convection in modulated nanofluid filled porous media

Abstract

A theoretical study of the effect of gravity modulation on a nanofluid filled porous medium subjected to a constant temperature gradient across is made. In particular the onset of convection in water based nanofluids containing conventional metallic and metal oxide particles (Cu‐water, Al2O3‐water, TiO2‐water, and Ag‐water) is investigated. The nanofluid behaves more like a single‐phase fluid rather than a conventional solid–liquid mixture. Darcy's law of flow through porous media and Boussinesq approximation are employed. Stability analysis based on the method of small perturbations is performed using the normal mode assumption. The resulting synchronous and asynchronous, restricted to subharmonic, instability modes are predicted directly through the Mathieu functions for different nanoparticle concentrations. It is found that Al2O3‐water nanofluid can be effectively used in applications involving gravity modulation.

Soret effect on stability of Darcy problem in a bidispersive porous medium with an exothermic chemical surface reaction

“…Numerous recent studies have focused on the stability of convection in such settings, for instance, Refs. [38][39][40][41][42][43][44][45][46][47][48][49][50][51]. Subsequently, we detail the partial differential equations governing fluid movement within a porous medium.…”