Enhanced heat transfer and flow control in Oldroyd-B hybrid nanofluids: A study on electro-osmosis effects and thermal characteristics

Electro-osmosis in hybrid nanofluids shows enormous potential for enhancing thermal conductivity and controlling fluid movement, which is important for improving heat transfer systems in industries and medical applications. This work examines the steady electroosmotic flow of thermally stratified Ol...

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Bibliographic Details
Main Authors: Alugunuri Raghu, Mahesh Garvandha, Nagaraju Gajjela, Adigoppula Raju
Format: Article
Language:English
Published: Elsevier 2025-09-01
Series:Results in Engineering
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Online Access:http://www.sciencedirect.com/science/article/pii/S2590123025027306
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Summary:Electro-osmosis in hybrid nanofluids shows enormous potential for enhancing thermal conductivity and controlling fluid movement, which is important for improving heat transfer systems in industries and medical applications. This work examines the steady electroosmotic flow of thermally stratified Oldroyd-B hybrid nanofluid comprising silver (Ag) and alumina (Al₂O₃) nanoparticles over an inclined, stretchy surface. We analyse the impacts of a variable heat source, thermal radiation, and stratification using the Cattaneo–Christov method. To analyse the physical behaviour, the governing nonlinear partial differential equations are reduced to ordinary differential equations via similarity transformations and solved numerically using the fourth-order Runge–Kutta method. Key findings: Electro-osmosis increases velocity by 16%, while Forchheimer decreases it by 23%. Hybrid nanoparticles enhance heat transport by 18%. Viscous dissipation and radiation augment thermal layer thickness by 20%, enhancing energy systems and biomedical applications. Additionally, surface drag increases with radiation but decreases with higher viscoelasticity (β₂). Quantitative results: The quantitative findings reveal that the boundary layer velocity increases from about 0.39 to 0.48 as me escalates from 0.2 to 1, signifying electro-osmotic enhancement. Nonetheless, it decreases from around 0.48 to 0.40 as Fs (0–0.9) increases, indicating decreased flow momentum attributable to heightened porous resistance resulting from the Forchheimer effect. The thermal profile θ(η) increases from approximately 0.34 to 0.54 at η = 1 with an increase in the heat source A∗(0.5–2.5), while it decreases from approximately 0.51 to 0.34 as the relaxation time β increases (0–3). Stratification δ decreases temperature from approximately 0.50 to 0.37, indicating contrasting thermal behaviors. These findings offer helpful advice regarding for the design and optimization of electrokinetic thermal systems in cooling technologies, energy devices, and biomedical applications.
ISSN:2590-1230