Nonlinear analysis of thermal convection and chaos in hybrid nanofluid layer.*

Abstract :

Jean Bio CHABI OROU

The characteristics of the nonlinear dynamics of thermal convection in nanofluids and their hybrid each confined in an infinite rectangular cavity and heated from below with the Fourier and Cattaneo-Christov heat flux model are studied. The truncated Galerkin approximation allowed one to find a low-dimensional Lorenz system in order to numerically study the transition from natural convection to chaotic behavior in a horizontal layer of hybrid nanofluid in the presence of a magnetic field. The different results showed that, for low rescaled Rayleigh numbers of the base fluid with or without the magnetic field, the addition of nanoparticles in a base fluid (water) allows to control the chaos, i.e. it is possible to suppress or enhance the chaotic convection. Also, during each transition, by varying the volume fraction, we found that the rescaled critical Rayleigh number of the base fluid containing the alumina nanoparticles is higher than that of the fluid containing the copper nanoparticles.