COALESCENCE OF A DROPLET CLUSTER SUSPENDED OVER A LOCALLY HEATED LIQUID LAYER

Experimental results on the coalescence of a dissipative structure “droplet cluster” obtained by means of high-speed thermal imaging are presented. It is found out that coalescence of a single cluster droplet with a liquid layer can generate a capillary wave on the interphase, and propagation of this wave causes coalescence of the whole cluster during several thousandths of a second. Cluster coalescence is accompanied by a temperature jump on the interphase. With cluster restoration, the surface temperature of a liquid layer returns gradually to the initial level. The interphase temperature under the droplet cluster can be both lower and higher than the interphase temperature without this cluster, i.e., the cluster can not only initiate both heat and mass transfer between liquid and gas, but also deteriorate it.