TY - JOUR
T1 - Effect of surfactants on the stability and thermophysical properties of Al2O3+TiO2 hybrid nanofluids
AU - Rehman, Abdul
AU - Yaqub, Sana
AU - Ali, Majid
AU - Nazir, Hassan
AU - Shahzad, Nadia
AU - Shakir, Sehar
AU - Liaquat, Rabia
AU - Said, Zafar
N1 - Publisher Copyright:
© 2023 Elsevier B.V.
PY - 2023/12/1
Y1 - 2023/12/1
N2 - This study investigates the influence of eight distinct surfactants on the stability, rheological characteristics, and thermophysical properties of hybrid nanofluids (NFs) containing Aluminum oxide (Al2O3) and Titanium dioxide (TiO2) in a Water-Ethylene Glycol (EG) mixture (60:40). The objective and novelty of this research is to choose the best surfactant for long run applications in terms of stability, viscosity and thermal conductivity. The results reveal that polyvinylpyrrolidone (PVP) exhibited the highest stability among all surfactants, surpassing others in zeta potential and visual stability over 60 days. Additionally, all the nanofluids exhibited Newtonian behavior. Surfactant addition increased viscosity, with polyethylene glycol (PEG) showing the highest enhancement of 37.2 % at 30 °C. Thermal conductivity increased with temperature, maximum TC enhancement of 8.3 % at 80 °C was given by PEG and oleic acid (OA), but these surfactants were unstable to be used in any application. In conclusion, PVP emerged as the most suitable surfactant for Al2O3-TiO2 hybrid nanofluids due to its exceptional stability, moderate viscosity, and TC enhancement. It enhanced the TC by 3.6% at 80°C and contributed 28.9% in viscosity increment at 30°C. This research contributes to the understanding of surfactant effects on nanofluid properties, particularly highlighting PVP's potential for long-term heat transfer applications.
AB - This study investigates the influence of eight distinct surfactants on the stability, rheological characteristics, and thermophysical properties of hybrid nanofluids (NFs) containing Aluminum oxide (Al2O3) and Titanium dioxide (TiO2) in a Water-Ethylene Glycol (EG) mixture (60:40). The objective and novelty of this research is to choose the best surfactant for long run applications in terms of stability, viscosity and thermal conductivity. The results reveal that polyvinylpyrrolidone (PVP) exhibited the highest stability among all surfactants, surpassing others in zeta potential and visual stability over 60 days. Additionally, all the nanofluids exhibited Newtonian behavior. Surfactant addition increased viscosity, with polyethylene glycol (PEG) showing the highest enhancement of 37.2 % at 30 °C. Thermal conductivity increased with temperature, maximum TC enhancement of 8.3 % at 80 °C was given by PEG and oleic acid (OA), but these surfactants were unstable to be used in any application. In conclusion, PVP emerged as the most suitable surfactant for Al2O3-TiO2 hybrid nanofluids due to its exceptional stability, moderate viscosity, and TC enhancement. It enhanced the TC by 3.6% at 80°C and contributed 28.9% in viscosity increment at 30°C. This research contributes to the understanding of surfactant effects on nanofluid properties, particularly highlighting PVP's potential for long-term heat transfer applications.
KW - Heat transfer
KW - Hybrid Nanofluids
KW - Stability
KW - Surfactants
KW - Thermal conductivity
KW - Viscosity
UR - http://www.scopus.com/inward/record.url?scp=85174391804&partnerID=8YFLogxK
U2 - 10.1016/j.molliq.2023.123350
DO - 10.1016/j.molliq.2023.123350
M3 - Article
AN - SCOPUS:85174391804
SN - 0167-7322
VL - 391
JO - Journal of Molecular Liquids
JF - Journal of Molecular Liquids
M1 - 123350
ER -