Magnetic fluid in ionizing electric field

• Published in: Journal of electrostatics Vol. 71; no. 3; pp. 467 - 470
• Main Authors: Marton, K., Tomčo, L., Cimbala, R., Király, J., Rajňák, I.M., Timko, M., Kopčanský, P., Kolcunová, I., Kurimský, J., German-Sobek, M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-06-2013
• Subjects: Electric fields; Fluid dynamics; Fluid flow; Fluids; Magnetic fields; Magnetic fluid; Magnetic fluids; Non-homogenous ionizing (strong) electric field; Nozzles; Orientation; Sprayability; Non-homogenous ionizing (strong) electric field; Sprayability; Magnetic fluid
• ISSN: 0304-3886; 1873-5738
• DOI: 10.1016/j.elstat.2012.12.022

This article describes influence of strong (ionizing) electric field on sprayability of magnetic fluid containing colloid particles with size in the range from 10 to 20 nm of magnetite Fe3O4. Magnetic fluids can be based for example on both transformer oil and physiological solution for application in medical using (in human medical science research), that supports a fluid colloidal system. Further component of magnetic fluid is surfactant. It is acting as surface-active substance that prevents from nanometric dimension particle settlement. Magnetic fluid gets off nozzle with diameter in range 0.3–1.0 mm from container in surroundings of ionizing (i.e. strong) electric field (E > 107 V m−1). As a consequence of action of electric field it gives out suppression surface tension in fluid what leads onwards to decomposition of magnetic fluid ligament at the end of nozzle. The diameter of nozzle oneself respects basic theoretical calculations in regards of fluid concentration and thereinbefore its selected size. Magnetic fluid in dependency on its used liquid base has weak-polar till polar orientation polarization character. It gives out sprayability in non-homogeneous electric field E in combination with magnetic field of intensity H. Orientation of vectors Ê and Ĥ, resp. induction of magnetic field B is defined by parallel or vertical direction. Results are confronted with measurements realized explicitly only at action of electric field (variable B = 0). In the case of magnetic field applications with permanent magnet together with electric non-homogeneous field it gives out unconventional dynamics of electrical charging particles of macroscopic dimension. Orientation particle track is influenced by orientation of field vector combinations. This phenomenon develops magneto-dielectric anisotropy, which oneself manifests behaviour of electrophysical quantities characterizing examination system. In consideration of technology utilization of this method it is very important to respect applied magnetic fluid concentration. Electrical characteristics were examined for volume concentration of magnetite particles in the range from 0.125% to 18%. Nevertheless efficiency optimization of given media suggests to boundary concentration of magnetic fluid of 4.0%, when it is in the regions of weak polar till polar material. Electrophysical research refers to exploitation of applied magnetic layer technology on dielectric insulating substances with inorganic origin as well as thin layer technology coating plastic foils created from macromolecular organic substance.