Heat Transfer Dynamics in Hydrophobic Microchannels: A Study of Non-Newtonian Fluids under Magnetic Influence

Document Type : Original Research Paper

Authors

1 Department of Mechanical Engineering, Sari Branch, Islamic Azad University, Sari, Iran

2 Islamic Azad university, Sari branch

10.22111/cnmst.2025.50927.1257

Abstract

This study explores the heat transfer (HT) characteristics of non-Newtonian fluids in hydrophobic microchannels influenced by magnetic fields (MFs). Using the Lattice Boltzmann Method (LBM), a detailed two-dimensional microscale model is developed to analyze the combined effects of flow slippage, viscous dissipation, and temperature jump phenomena. The power-law model is employed to represent the non-Newtonian fluid behavior accurately. The results demonstrate that increasing the slip length significantly enhances convective HT by modifying boundary layer dynamics. However, this enhancement is mitigated by the opposing effects of temperature jump and viscous dissipation. The introduction of a magnetic field further alters the flow dynamics, with the Lorentz force optimizing velocity profiles and substantially boosting HT efficiency. The results show that the presence of magnetic field with Ha=20 enhances heat transfer 3.3% and 4.2% at B=0 and B=0.06 respectively for non-Newtonian fluid flow with n=0.9. These findings underline the intricate interplay between magnetic field intensity, fluid rheology, and surface properties, offering valuable guidance for designing advanced thermal management systems in microchannel applications.

Keywords