关键词:

电水动力学;汽泡, 电应力;沸腾换热

Abstract:

In order to make further study on the electrohydrodynamic enhancement mechanisms of boiling heat transfer,the growth process of boiling bubbles in the electric field was visually investigated with a high-speed camera.The bubble dynamic growth process was observed in the electric field and boiling heat transfer action influenced by the change of bubble behaviour in the electric field was analyzed.Experimental results showed that the bubble elongated along the direction of the electric field.The bubble’s aspect ratio and departure frequency increased with increasing electric field intensity, while its departure volume decreased with increasing electric field intensity.The bubble deformation resulted primarily from the effect of electric stress acting on the bubble surface.The bubble became slender and longer along the direction of the electric field because the electric stress compressed the bubble in the equatorial direction and extended the bubble along the axial direction.The boiling heat transfer coefficient and critical heat flux increased due to the change of bubble behavior in the electric field.

Key words:

电水动力学;汽泡, 电应力;沸腾换热