RETRACTED: Squeeze film lubrication between two different spheres: MHD- couple stress fluid model
Annotatsiya
This study explores the squeeze film lubrication between two dissimilar spheres using a couple stress non-Newtonian fluid subjec to characteristics of an external magnetic field. A modified Reynolds-type expression is derived by applying Stokes theory alongside magneto-hydrodynamic (MHD) motion equations and the continuity eq. A closed-form expression for the squeeze film pressure is captured and used to analyse the lubrication performance. The impacts of key non-dimensional variables—including the Hartmann number, couple stress parameter, radius ratio, and film height—are thoroughly examined. The obtained outcomes show that the existence of a magnetic field significantly improves squeeze film features. Specifically, increasing the Hartmann number enhances pressure generation and load-carrying capacity due to stronger electromagnetic damping effects. The incorporation of couple stress fluid behaviour, accounting for the microstructure of the lubricant, leads to greater film stability and resistance to deformation. The radius ratio of the spherical surfaces plays a crucial role in improving lubrication efficiency, with larger values providing better performance. On the other hand, an increase in film height shows a reverse effect, lowering the squeeze film pressure and overall performance. These insights demonstrate the sensitivity of the system to both fluid properties and geometrical configurations. This work is particularly relevant to high-performance applications where precise lubrication and stability are essential. Potential applications include magnetic bearings, automotive dampers, precision manufacturing, and biomedical devices such as artificial joints and implants. The study highlights how MHD and couple stress effects can be leveraged to design more robust and efficient lubrication systems.