Utilization COSMOS/EMS for Analysis of Magnetic Field of Pressure Force Elastomagnetic Sensor
Anna Hodulikova · 2010
The article focuses on simulation of magnetic field allocation in core of elastomagnetic force sensor and the solution for cases when the sensor is and is not affected by external pressure force. 3D model of elastomagnetic force sensor had been created for solution of field in sensor's core. The method of finite elements was used for counting the parameters, which describe the field. Elastomagnetic sensors belong to the group of nonlinear systems. They are based on existence of Villaris effect. 1. Elastomagnetic sensor 1.1 Elastomagnetic effect The principle of elastomagnetic sensor is based on the existence of elastomagnetic (Villari) effect. It is observed in a ferromagnetic material when an external force is applied to this material and deforms it. Because of this deformation, the relative distances of atoms in crystal structure are changed . The effect manifests as the change of magnetic polarization or magnetic induction at the unchanged magnetic field strength applied on ferromagnetic material. If this material is isotropic before the application of external pressure, it becomes anisotropic after the application of pressure. The magnetic properties are characterized by permeability and it will be changed in accordance with acting force. Dependence of the change of permeability μ Δ on mechanical tension σ describes the next relation obtained from thermodynamic equilibrium in ferromagnetic material in alternating harmonic magnetic field: λ μ