Experimental Study of The Effect of Flow Rate and Concentration of Graphene-Water Nanofluid and Finding the Optimal Conditions Using Taguchi Method

In this paper, by sodium dodecyl sulfate as a surfactant, graphene nanoplate (GNP) was stabilized in a water-based fluid. The prepared nanofluid in concentrations of 0.01% -0.145% wt. was placed in a gasket plate heat exchanger in the presence of cold fluid (deionized water). All experiments were performed for laminar flow in the range of Reynolds numbers of 500-1500. The nanofluid was investigated on the overall coefficient of heat transfer and pressure drop. The concentration increase causes both to increase at the same time. As a result, heat exchange efficiency and thermal effectiveness of the nanofluid were also analyzed. The highest thermal effectiveness (89%) and efficiency (1.244) occur at a minimum flow rate (2 lpm) and maximum concentration (0.145% wt.) Taguchi method was used to find the optimal conditions (higher thermal effectiveness) and confirming the validity of the experiments. It was also found that the decrease in flow rate (98.56%) has a greater effect on the results of thermal effectiveness than the increase in concentration (0.404%). The error rate was 0.018%, which shows the accuracy of the results.