The CFD simulation of heat transfer characteristics of a nanofluid ina circular tube under convective heat transferwas considered using the fluentsoftware (version 6.3.26) in the laminar flow. Al2O3nano- particles in water with concentrations of 0.5, 1.0, 1.5, 2 and 2.5% were studied in the simulation. All thermo-physical properties of nanofluids were temperature independent. It was concluded that heat transfer coefficient increased with the Peclet number. Furthermore, it increased by increasing the concentration of nano-particles in nanofluid. The simulated data were in good agreement with the literature (with the discrepancy of less than 10%).
