Numerical simulation of natural convection heat transfer in a trapezoidal enclosure filled with nanoparticles

In this paper, we have investigated unsteady natural convection flow and heat transfer inside a trapezoidal enclosure
filled with nine different types of nanofluids having various shapes of the nanoparticle following Tiwari
and Das mathematical model. The left and right walls of the enclosure are kept at different temperatures, while
the top and bottom walls of the cavity are thermally insulated. The Galerkin weighted residual based finite element
method has been employed to solve the governing partial differential equations after converting them into
a nondimensional form. The simulation is carried out through the pde solver COMSOL Multiphysics with Matlab
interface. Comparison with the previously published result is made for a special case and an excellent agreement
is found. The effects of various model parameters such as the Rayleigh number, the aspect ratio, the volume
fraction and the shape factor of the nanoparticles on streamlines and isotherms have been displayed graphically
and discussed. The heat transfer augmentation for various combinations of pertinent parameters has also been
presented in light of the average Nusselt number on the left heated wall.