Experimental investigation on pool boiling heat transfer of ZnO, and CuO water-based nanofluids and effect of surfactant on heat transfer coefficient

摘要

Comparison of boiling performance of nanofluids and mixtures of nanofluids with surfactant is an objective of this research. Experimental investigation has been performed with different heat flux and concentrations of nanopartides and surfactant. CuO and ZnO water-based nanofluids are used and sodium dodecyl sulfate (SDS) is used as surfactant. The size of nanopartides is measured from Field Emission Scanning Electron Microscopy pictures. Roughness of rod heater is calculated by using Atomic Force Microscopy picture. The pure water is tested after each run with nanofluid and mixture of nanofluid with SDS and the results are presented. Result from experiments demonstrates that the addition of SDS to nanofluids solution resulted in improving boiling performance. Experimental results also show an inefficient process by excluding surfactant An optimum value for heat transfer coefficient is found by increasing of surfactant concentration within CuO nanofluid (0.01wt％CuO). Pictures of coated and clean surface in boiling pure water are employed for understanding the dynamics of bubbles. Corenflo constant (h_o) is utilized to show the effect of addition of nanopartides and SDS in boiling performance of base fluid.