Thermophoresis of a cylindrical particle embedded in a porous medium saturated by a micropolar fluid

Abstract

The present study examines the thermophoresis of a cylindrical particle in a direction perpendicular to its axis in the Brinkman medium. To describe the behaviour of micropolar fluid driven by a thermal gradient within such a porous medium, the modified Brinkman’s equation is applied while considering low Reynolds and Péclet numbers. The governing equations for both the particle and the medium are solved using the separation of variables technique. The boundary conditions applied at the particle surface are thermal jump and heat flux continuity, with viscous slip, thermal creep, thermal stress slip and microrotation slip. The main objective of the research is to derive the expressions for thermophoretic velocity and thermophoretic force of a cylindrical particle. Graphical representations illustrate the thermophoretic velocity and force of the particle for various physical parameters, including the permeability, micropolarity parameter, thermal stress slip parameter, viscous slip parameter, Knudsen number, and thermal conductivity parameters. The results show that an increase in the micropolarity parameter decreases both the thermophoreti velocity and the force. Additionally, thermophoretic velocity increases with higher permeability, while the thermophoretic force decreases with increasing permeability and the thermal conductivity ratio. The findings of this research align with previously published studies and hold potential applications in industrial processes, including filtration, heat exchangers, air cleaning, and manufacturing thermal precipitators.