Stability and thermal performance of silica nanofluid in water block heat sink

Thermal performance has become one of the main issues in electronic industries in line with prevailing development. Conventional working fluid such as distilled water (DI) often used by electronic devices has some shortcomings on the efficiency of transferring heat for cooling purposes. Hence, nanofluid is a promising alternative as it will be able to help improvising and more competent than subsist working fluid. In this experiment, water-based nanofluid with gum Arabic (GA) as surfactant is used. The main purpose of this study is to investigate the effect of GA and different volume concentrations of silica nanoparticles in DI on thermal performance and stability of nanofluids. Various volume percentage (vol%) of nanoparticles (0.1 vol%, 0.3 vol% and 0.5 vol%) were used and nanofluid was dispersed using sonication process for 20 min. Temperature distribution on heat sink water block with range of flow rates (0.05 m3 h-1 to 0.1 m3 h-1) and heating power of 20 W was used to determine the efficiency of nanofluid as heat transfer fluids. The result shows that fluid contact surface temperature reduced with addition of silica at various flow rates as compared to that of distilled water. The thermal resistance of nanofluids reduced at all flow rates, reduction of 20% in thermal resistance is observed at all flow rate compared to DI. Higher heat transfer coefficient (HTC) is observed for nanofluids compared with DI because of their higher thermal conductivity. Comparison on experimental data with theoretical data calculated based on Maxwell theory indicated that thermal conductivity increased with increasing silica content with more significant data shown by experimental result. Thermal conductivity enhancements increased with increasing silica concentration in nanofluids. Finally, according to the results, it can be claimed that silica nanofluid can be introduced as an alternative fluid in heat transfer system. © Penerbit Universiti Sains Malaysia, 2019.