Motion dynamics of a cluster of monodispersed liquid droplets in another immirscible liquid

The paper describes an experimental study of the process in which a cluster of monodisperse droplets of isoparaffin oil ascends to the surface in distilled water in a range of Reynolds numbers Re = 200 $\div$ 800. It is shown that the initial volume concentration of droplets in the cluster is one of the main parameters determining its dynamics. The study also touches upon the motion of two types of clusters, characterized by the presence or absence of collisions of the droplets contained in it. Experimental dependences of the rate of ascent of the droplet cluster on the Reynolds number are obtained for different values of the initial volume concentration of droplets. The limiting value of the initial volume concentration of droplets is determined, corresponding to the onset of cluster motion with a velocity exceeding the velocity of a single droplet.