A Characteristic-Based Numerical Simulation of Water-Titanium Dioxide Nano-Fluid in Closed Domains

A new characteristic-based method is developed and used for solving the mixed and forced convection problems. the nano-fluid flow with heat transfer is simulated with a novel characteristic-based scheme in closed domains with different aspect ratios. for this purpose, a fortran code has been written and developed. water as a pure fluid and water-titanium dioxide as a nano-fluid were considered. the governing equations are solved by the finite volume utilizing a characteristic-based scheme for the convective fluxes. the simulation is done at grashof numbers from 100 to 10^4, reynolds numbers from 100 to 1000, and volume fractions of nano-particles from 0% to 10%. streamlines, isotherms, friction factor, and mean nusselt number are obtained in various conditions. the convective behavior of nano-fluid is explored as a function of several parameters, such as grashof number and geometrical parameters. results indicate that the mean nusselt number for the nanofluid is up to 23% more than that of pure water.