Experimental and machine learning insights on heat transfer and friction factor analysis of novel hybrid nanofluids subjected to constant heat flux at various mixture ratios

• Published in: International journal of thermal sciences 2025-03, Vol.209, p.109548, Article 109548
• Main Authors: Kanti, Praveen Kumar, Wanatasanappan, V. Vicki, Sharma, Prabhakar, Said, Nejla Mahjoub, Sharma, K.V.
• Format: Article
• Language: English
• Subjects: Al2O3-GO hybrid nanofluid; Heat transfer; MLP-ANN; Thermal conductivity; Thermal performance index
• ISSN: 1290-0729
• DOI: 10.1016/j.ijthermalsci.2024.109548

This study explores the combined effects of aluminum oxide (Al₂O₃)/graphene oxide (GO) hybrid nanofluids in 50:50 and 80:20 ratios, offering a notable improvement over conventional Al₂O₃ or GO nanofluids. It delivers a thorough comparison of thermophysical properties such as thermal conductivity and viscosity and heat transfer performance across water, Al₂O₃ nanofluids, and the Al₂O₃/GO hybrids. Nanofluids at 0.1–0.5 % volume concentrations were tested in a horizontal circular pipe under constant heat flux and turbulent flow with an inlet temperature of 60 °C. The maximum Nu enhancements of 64, 56 and 41 % were noted for Al₂O₃/GO (50:50), Al₂O₃/GO (80:20), and Al₂O₃ nanofluids, respectively at 0.5 vol%, compared to water. The maximum pressure drop of Al2O3/GO (50:50) nanofluid is 5.64 and 8.3 % greater than that of Al2O3/GO (80:20) and Al2O3 nanofluid, respectively at 0.5 vol%. The peak thermal performance index of 1.56, 1.48, and 1.33 is observed for Al₂O₃/GO (50:50), Al₂O₃/GO (80:20), and Al₂O₃ nanofluids. The integration of a multi-layer perceptron artificial neural network further enhances accuracy in predicting thermal performance, surpassing the precision of conventional empirical models. The adopted model showed excellent predictive accuracy, with correlation coefficients of 0.98493 in training, 0.9837 in validation, and 0.98698 in testing. •Novel Al₂O₃/GO nanoparticle blends (80:20 and 50:50) enhance thermal conductivity and heat transfer.•Synthesis achieved through sol-gel and Hummer's methods.•Experimental validation under turbulent flow and constant heat flux.•Al₂O₃/GO (50:50) mixture significantly boosts Thermal Performance Index.•Accurate predictive modelling using MLP-ANN for advanced thermal systems.