How do magnetic fields influence heat transfer in fluids? This study explores the phenomenon of thermomagnetic convection in magnetic fluids confined within a cylindrical geometry and subjected to a homogeneous magnetic field. This work is motivated by the discovery of a novel thermal instability. A composite cylinder with inner heating is considered, reflecting the symmetry of experimental setups. The research derives the general condition for the existence of a potentially unstable stratification in the magnetic fluid. Employing linear stability analysis, the critical external induction for the onset of thermomagnetic convection is determined for both dilute and non-dilute magnetic fluids. By comparing the thresholds for dilute and nondilute fluids, the researchers propose an experimental method to classify the fluid type. These findings contribute to a better understanding of heat transfer mechanisms in magnetic fluids, relevant to applications ranging from thermal management systems to advanced materials processing.
As a contribution to Physics of Fluids, this study is well-suited to the journal's scope. The paper presents detailed analysis and modeling of thermomagnetic convection. The study advances fundamental knowledge of fluid dynamics with relevance to various engineering applications, fitting the journal's interdisciplinary approach.