Numerical study of heat transfer enhancement for mono and hybrid nanofluids flow in a straight pipe

Abstract

In recent years, there has been an increasing interest in heat transfer enhancement using nanofluids in channels due to current devices become smaller and more compact and are expected to perform better. Thus, we attempt to introduce hybrid nanofluids flow in a straight pipe using Ansys Fluent software. The simulation was prepared with certain specific parameters such as the hydraulic diameter is set at 10mm, the flow is a continuum, the Reynold number in the range of 5000 to 30000, k-ε turbulent model used in this simulation, the inlet temperature 297 K, and the uniform temperature along the pipe at 313 K. This study was carried out on Al2O3+Cu / water hybrid nanofluids to analyse the thermal improvement and friction factor of nanofluids occur in a straight pipe. Then, the numerical results obtained were compared between mono and hybrid nanofluids. It was found that the mono nanofluids at 1% and 4% indicate a significant increase in Nusselt number at 17% and 24% respectively and hybrid nanofluid increase at 2% to 5.6% compared to base fluid. Whereas the friction factor remains similar for all the nanofluids. However, the performance evaluation criterion (PEC) has shown that hybrid nanofluids remain lower than mono nanofluids.