Constitutive equations of Micropolar electromagnetic fluids

The fundamentals of electrodynamics of Micropolar fluids are briefly introduced. Balance laws of mass, linear momentum, angular momentum, energy and entropy for Micropolar Fluid Dynamics (MFD) are integrated with Maxwell’s equations. The thermodynamically admissible constitutive equations for Micropolar fluids are obtained from Onsager’s theory and Wang’s representation theorem based on the principle of objectivity. Couple Stress Theory (CST) and Newtonian fluid are shown as the special cases of MFD. From constitutive equations, it is found that, even without any external electromagnetic field, micromotion can induce bound current, a missing phenomenon in classical continuum physics. The linear formulation is specialized for Magneto-Micropolar Fluid Dynamics (M2FD) for the application of plasma physics.

► Wang’s representation theorem and Onsagers reciprocal relations are utilized to derive the constitutive equations for Micropolar electromagnetic fluids.
► A new physical phenomenon, gyration-induced current, is introduced.
► A set of field equations are proposed for Magneto-Micropolar hydrodynamicss.