Se-Hee Lee and Ho-Young Lee, "Numerical and Experimental Validation to the Ability of Magnetoconvection to Cool Vegetable-Based Transformer Oil With Magnetic Nanoparticles", IEEE TRANSACTIONS ON MAGNETICS, VOL. 55, NO. 7, JULY 2019.

Abstract:

This paper describes an investigation into the combined effects of magnetoconvection and an externally applied magnetic field on the thermal performance of vegetable oil-based magnetic nanofluids with different volume fractions of magnetic nanoparticles. The mineral-based oil has conventionally been used in power transformers because it has high dielectric strength and good cooling performance under normal operating conditions. Because of the environmental impact, eco-friendly vegetable-based transformer oils have been substituted for mineral-based insulating oils. To date, related studies have only reported on the characteristics of dielectric breakdown in vegetable oil-based magnetic nanofluids without any real electromagnetic systems. Furthermore, the thermal characteristics of vegetable oil-based magnetic nanofluids have not yet been fully investigated. Thus, the aim of this paper was to examine the cooling performance by adding magnetic nanoparticles to the vegetable-based transformer oil. To quantitatively analyze this effect, a multi-physics technique that incorporates magnetic-thermal-fluidic fields was developed as based on quasistatic magnetic field approximation and conjugate heat transfer. To validate the numerical results, corresponding experiments were successfully carried out via application in a simple electromagnetic system with varying insulating liquids.