Bubble Dynamics Simulation in Transformer Oil under AC Electric Field

doi:10.16182/j.issn1004731x.joss.201612029

Abstract

Abstract: The dynamics of gas bubbles in transformer oil was theoretically explored. A numerical model was introduced for the bubble dynamics in the transformer oil under AC electric field. The electrodynamic force was calculated by integrating the Maxwell stress tensor on the surface of the bubble, and then the bubble trajectory was obtained through the force calculation of the bubble under the AC electric field. Notably, trajectories calculated indicate the bubble aggregation in concentrated area of the electric field between the needle-plane electrode, and different bubble radius will affect the trajectory of the bubble. Also, different bubble radiuses cause a small change in the equilibrium position of bubble between the electrodes. It is concluded that the bubble can play a catalytic role in the breakdown of the oil gap.

Key words: bubble trajectory, aggregation, transformer oil, electrodynamics force

CLC Number:

TM854

Zhao Tao, Liu Yunpeng, Lü Fangcheng, Liu Shan. Bubble Dynamics Simulation in Transformer Oil under AC Electric Field[J]. Journal of System Simulation, 2016, 28(12): 3081-3087.

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