Kadivar, MohammadrezaSharifpur, MohsenMeyer, Josua P.2022-12-022022-12-022021Mohammadreza Kadivar, Mohsen Sharifpur & Josua P. Meyer (2021) Convection Heat Transfer, Entropy Generation Analysis and Thermodynamic Optimization of Nanofluid Flow in Spiral Coil Tube, Heat Transfer Engineering, 42:18, 1573-1589, DOI: 10.1080/01457632.2020.1807103.0145-7632 (print)10.1080/01457632.2020.18071031521-0537 (online)https://repository.up.ac.za/handle/2263/88611In this study, heat transfer, flow characteristics, and entropy generation of turbulent TiO2/water nanofluid flow in the spiral coil tube were analytically investigated considering the nanoparticle volume fraction, curvature ratio, flow rate and inlet temperature between 0.01–0.05 percent, 0.03–0.06, 1.3–3.3 l/min, and 15–27 °C, respectively. Results showed that the augmentation of the nanoparticle volume fraction increased the Nusselt number and friction factor up to 11.9% and 1.1%, respectively, while it reduced the entropy generation number up to 10.9%. Reducing the curvature ratio led to a maximum of 11.1% increase in the Nusselt number, while it resulted in a 5.6% increase in the entropy generation number. A decline in the inlet temperature from 21 °C to 15 °C proceeded a 28.4% and 7.1% increase in the heat transfer and pressure drop, respectively. The total entropy generation reduced with increasing nanoparticle volume fraction. For a low Reynolds number, a decrease in the curvature ratio led to a reduction in the total entropy generation, while reducing the curvature ratio was detrimental for a high Reynolds number. Analytical relations for optimum curvature ratio and optimum Reynolds number were derived. For the range of parameters studied in this paper, a range of optimum Reynolds number from 9000 to 12,000 was proposed.en© 2021 Taylor & Francis Group, LLC. This is an electronic version of an article published in Heat Transfer Engineering, vol. 42, no. 18, pp. 1573-1589, 2021. doi : 10.1080/01457632.2020.1807103. Heat Transfer Engineering is available online at : http://www.tandfonline.comloi/uhte20.Convection heat transferEntropy generation analysisThermodynamic optimizationNanofluid flowSpiral coil tubeEngineering, built environment and information technology articles SDG-04SDG-04: Quality educationEngineering, built environment and information technology articles SDG-07SDG-07: Affordable and clean energyEngineering, built environment and information technology articles SDG-09SDG-09: Industry, innovation and infrastructurePostprint Article