Finite element simulations for natural convective flow of nanofluid in a rectangular cavity having corrugated heated rods

Abstract

In this study, numerical simulations of natural convection in a partially heated rectangular cavity containing water-based copper oxide nanofluid (CuO–water) have been carried out. The flow field and heat transfer inside the cavity are influenced by two corrugated heated rods. The governing partial differential equations are transformed to dimensionless coupled nonlinear partial differential equations using some suitable variables. For the thermophysical properties of nanofluid, Koo and Kleinstreuer–Li model is implemented in the governing equation. Numerical solutions of the resulting system of equations are obtained utilizing finite element method. The simulations for flow field and thermal distribution are portrayed in terms of line graphs, streamlines and isotherms. The results are executed for various Rayleigh numbers $$(10^4\le {\mathrm{Ra}} \le 10^6)$$ , nanoparticle volume fractions $$(0.0\le \phi \le 0.2)$$ , amplitudes of the corrugated heated rods $$(0.05\le A_{\mathrm{m}} \le 0.2)$$ and wavelength numbers $$(0 \le n \le 20)$$ . Results depict that the thermal distribution and flow field are getting stronger because of increasing Ra and n. The impact of nanoparticle volume fraction is found to be useful in intensifying the heat transfer rate because of dominant convection. It is worth mentioning that with an increase in $$A_{\mathrm{m}}$$ the thermal distribution in the entire cavity is control by convection.