INVESTIGATION OF THE MECHANISMS GOVERNING THE PARACHUTE-TYPE FRAGMENTATION PROCESS IN GAS FLOW OVER A PLANAR LIQUID SURFACE
D.A. Sergeev1,2,3, Yu.I. Troitskaya1,2, A.N. Zotova1, O.S. Ermakova1, I.M. Kraev1
1Institute of Applied Physics of the Russian Academy of Sciences, Nizhny Novgorod, Russia
2Kutateladze Institute of Thermophysics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
3Nizhny Novgorod State Technical University, Nizhny Novgorod, Russia
Keywords: gas-liquid flow, parachute-type fragmentation, hydrodynamic instability
Abstract
This paper presents the results of a study of the parachute -type fragmentation process. This process serves as a source of the dispersed phase in various natural and industrial multiphase flows in which a planar liquid surface is exposed to a gas stream. Experiments are performed using shadowgraph visualization and high-speed imaging, with artificial initiation of the process under controlled conditions. Computer-based image processing is used to determine the dome dimensions and film thickness, as well as to detect the resulting droplets and quantify their number. Based on the analysis of the results, it is concluded that rupture of the dome film occurs due to Rayleigh-Taylor instability. The dependence of the average number of droplets produced by rupture of the parachute dome film on the governing parameter-the Weber number-is obtained.
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