SYNTHETIZATION OF BANANA-STEM FIBRE NANOPARTICLES TO PROMOTE THERMAL CONDUCTIVITY OF NANOFLUIDS IN COOLING SYSTEMS
Abstract
Cooling is one of the most significant and challenging aspects of heat transfer applications; for instance, heat from power generation requires a high amount of cooling. Most chemical processes are exothermic reactions, which demands faster and more effective cooling at different stages. Recent studies shows that researchers are strongly concerned on how to properly utilize the value of banana fibre and turn it into a treasure. In this study, the thermal conductivity of nanofluids prepared from banana-stem fibre nanoparticles have been investigated both as a function of concentration of banana-stem fibre nanoparticles as well as temperature ranges between 20 and 60 °C. For decades, water or a mixture of water and antifreeze has been used in automotives radiators as coolants for exchanging heat. As thermal conductivity offered by these fluids is low, hence their applications in modern equipment have reached their upper limits. Advancement in nanotechnology had result in a new kind of fluids known as “nanofluids”, whose thermal performance is greater compared to conventional coolants. The focus of this research is on the application of banana stem fibre nanoparticles nanofluid in a cooling system. Nanofluids of different volumetric concentrations (0.3, 1.5 and 3%) were prepared and then experimentally their heat transfer performance was determined using transient hot-wire apparatus. Based on the calibration results from the transient hot-wire method, the measurement error was estimated to be within 2%. The investigated thermophysical properties of the prepared nanofluids at different volume fractions (0.3,0.6,0.9,1.2 and 1.5%) and water were simulated using computational fluid dynamics (Auto desk CFD) software for its cooling performance. From the result of water simulation, the inlet and outlet temperatures generated by the solver are 23.80 and 104.87oC respectively. While from the results of nanofluid simulation at 0.3% volume fraction of nanofluid the solver generated the inlet and outlet temperature as 9.41oC and 110.23oC, while for 0.6 volume fraction of nanoflid the solver generated inlet and outlet temperature as 7.01oC and 103.81o C. In addition, the solver generated the inlet and outlet temperature of 0.9% volume fraction of nanofluid as 10.88oC and 104.44oC. For 1.2% volume fraction of nanofluid the solver generated inlet and outlet temperature as 9.26 and 102.63oC. Finally, the solver generated the inlet and outlet temperature for 1.5% volume fraction as 9.20 and 102.57oC respectively. Therefore, it was concluded that the nanofluids prepared from banana nanoparticles give better predictions for the effective thermal conductivity enhancement and effective cooling medium in heat exchanger.
