Analytical integro-differential representation of flow fields for the micropolar Stokes flow of a conducting ferrofluid

• Published in: IMA journal of applied mathematics Vol. 80; no. 3; pp. 839 - 864
• Main Authors: Vafeas, P., Papadopoulos, P. K., Hatzikonstantinou, P. M.
• Format: Journal Article
• Language: English
• Published: 01.06.2015
• Subjects: Computational fluid dynamics; Fluid flow; Magnetic fields; Mathematical analysis; Mathematical models; Representations; Stokes flow; Three dimensional
• ISSN: 0272-4960; 1464-3634
• DOI: 10.1093/imamat/hxu016

Practical physical applications of mathematical nature are frequently met in engineering technology and involve the low-Reynolds number flow of micropolar conducting fluids under the effect of magnetic fields. Here, we consider the three-dimensional (3D) creeping motion (Stokes flow), in steady state, of a non-conductive colloidal suspension of ferromagnetic material embedded within an electrically conductive, viscous and incompressible, carrier liquid. In such cases, the ferromagnetic particles behave as rigid magnetic dipoles and react in the presence of an externally applied magnetic field, which is of general form and arbitrarily orientated in the 3D space. Therein, an induced magnetic field of minor significance is created, while the effective viscosity of the fluid is increasing and an additional magnetic pressure is appeared. The consistency of the governing set of partial differential equations with the principles of both ferrohydrodynamics and magnetohydrodynamics is established by taking into account magnetization and electrical conductivity of the fluid, respectively. Our main intension is to use the potential representation theory to improve previous models and construct a new complete and unique integro-differential representation of the magnetic Stokes flow of conducting liquids, valid for any non-axisymmetric geometry, which provides the velocity and total pressure fields in a closed form and in terms of easy-to-find potentials, via a semi-analytical formalism. To demonstrate the usefulness of our analytical approach, we assume a degenerate case of the aforementioned method to simulate the creeping flow of a micropolar fluid with conductive properties inside a circular duct.