Numerical Study on Motion of a Single Bubble Exerted by Non-uniform Electric Field
Y. Takata, H. Shirakawa, K. Tanaka and T. Ito
Numerical analysis has been performed on a bubble growth and deformation in an electric field in order to disclose the mechanisms of boiling heat transfer enhancement by EHD (Electro-Hydrodynamic) effects. Transient Navier-Stokes and Maxwell equations were solved simultaneously for both liquid and vapor phases in a two-dimensional cylindrical co-ordinate systems making use of VOF (Volume of Fluid) method. The bubble motion in liquid R113 under atmospheric pressure has been simulated. First, an elongation of a single bubble in a uniform electric field is simulated and the oblateness of the bubble is in good agreement with Garton’s analytical and experimental results. Second, the bubble deformation process in a non-uniform electric field was simulated. A bubble, initially attached to the lower electrode, starts to deform and finally takes off from the lower electrode. The shape of the bubble depends on the intensity of the electric field. The behavior of bubbles, the velocity vectors, and the contour of the electric field are shown, and an experiment has been performed to verify the results of the numerical simulation.