Analysis, prediction, and optimization of heat transfer coefficient and friction factor of water-$${\mathrm{Al}}_{2}{\mathrm{O}}_{3}$$ nanofluid flow in shell-and-tube heat exchanger with helical baffles (using RSM)

The influence of the tube pass ratio employed, the twisted helical baffle, and Al2O 3-water nanofluid as the base fluid is investigated in this study by computational analysis. When they add Al2O3, the heat transfer in the shell-and-tube heat exchangers (STHX) increases. Three parameters are chosen for optimization in this research. The heat transfer coefficient activities and the friction factor of a heat exchanger shell are studied in this way. The tube pass ratio (PR), the baffles space ratio (BS), and the Reynolds number are all examined. Reynolds number (Re) has the greatest influence on enhancing heat transfer among the studied factors, followed by tube PR and BS. The findings suggest that increasing the Re and Tube PR while reducing the baffle BS boosted heat transfer while raising the Re decreases the friction factor. Apart from having a direct influence on the efficiency of the STHX, each of the parameters has an interaction effect on the others. More heat transfer is recorded at the greatest Re, the highest value of the tube PR, and the lowest value of the BS.