ABSTRACT
The heat convection can passively be enhanced by changing flow geometry and boundary conditions or by enhancing fluid thermophysical properties. Nanofluids are a new kind of heat transfer fluids containing a small quantity of nanosized particles that are uniformly and stably suspended in a liquid. Convective heat transfer with nanofluids can be modeled using the two-phase or single-phase approach. The first provides the possibility of understanding the functions of both the fluid phase and the solid particles in the heat transfer process. The second assumes that the fluid phase and particles are in thermal equilibrium and move with the same velocity. The single-phase approach has been used in several theoretical studies of convective heat transfer with nanofluids. Nanofluids have numerous industrial applications, where efficient heat dissipation is necessary. Elliptic cross section tubes have drawn special attention since they were found to create less resistance to the cooling fluid, which results in less pumping power.
