Abstract: With the demand for energy continues to grow globally, there is a need to make heat transfer equipment more energy efficient. At one hand, the exponential growth of electronics, communication and computer technology and their choice to go for miniaturization has put added pressure on the designer to create efficient thermal management devices for these systems. Particularly thermal conductivity of a fluid plays a vital role in the development of energy-efficient heat transfer equipment. An innovative idea is to suspend nano-sized solid particles in the fluid to improve heat transfer characteristics of the fluid. Nanofluids are the suspension of nanometer-sized particles in base fluids such as water and ethylene glycol. In convective heat transfer, number of other factors along with thermal conductivity affects heat transfer performance, so careful examination of convective heat transfer using nanofluid is required. For optimum condition of nanofluids, some experimentation is required for better result. As experimentation is time consuming process, nanofluids are analyzed by using CFD (computational fluid dynamics) approach. This approach has attracted the attention of researchers in the past decade, though the mechanism is not fully understood yet. So in this work, a systematic computational fluid dynamic investigation of Al2O3/water nanofluid with different volume fraction by varying Reynolds number and constant wall temperature boundary condition has been carried out adopting single phase and two phase approach and the results are compared with experimental results and theoretical correlations. Both the single phase and two phase models results show a good agreement with experimental data and theoretical correlations but two phase model gives prediction of heat transfer rate compared to the single phase model.

Keywords: Nanofluid, convective heat transfer, CFD, Al2O3 nanoparticles, Reynolds number.