Experimental study of the influence of bubble interaction on their characteristics during transient boiling in a flow of subcooled liquid

The paper presents the experimental results on transient nucleate boiling on the heater surface with rapidly increasing surface temperature. According to the results of high-speed video recording with a frequency of 180 000 frames per second and a spatial resolution of 5.5 urn per pixel, the input data for existing models of heat transfer during nucleate boiling must be refined to take into account the existence of cluster and pulsating bubbles. It has been established that bubbles, interacting through the exchange of momentum, heat and vapor mass, accelerate activation of neighboring vaporization sites, so the clusters of bubbles can form at the initial stage of covering the heater surface with vapor. The main characteristics of single, cluster and pulsating bubbles have been studied for the wall superheating from 0 to 14 K above the temperature of nucleation beginning and flow subcooling from 23 to 103 K.