Analysis of a textural atomization process

Abstract

The experimental work reported in this paper addresses the question of the description of a textural atomization process including the atomizing structures and the resulting drops. Textural atomization process designates a deformation leading to drop-production localized on the liquid-gas interface of a liquid flow: droplets appear like peeled from the interface. Such a process usually takes place in the near field region, i.e., near the injector. In the present work, the textural atomization process of a cavitating liquid flow is considered. A multiscale method is applied to describe this process and the concept of equivalent-system of cylinders is introduced and sued to provide a mathematical expression for it. In parallel, a mathematical formulation for the measured drop diameter-distribution is presented also. The connection between the atomization process and the spray is established on the basis of these mathematical formulations. It brings a model in which the main-drop diameter-distribution is controlled by the size distribution of the ligaments of the textural atomization process, and the satellite-drop peak links with their deformation. This analysis demonstrates that the scales for which the successive derivatives of the scale distribution are zero are characteristic lengths of the spray drop diameter distributions. These results have a potential to elaborate new simulation strategies for instance. 1.

Experimental and Analytical Study of under Water Pressure Wave Induced by the Implosion of a Bubble Generated by Focused Laser

“…For example, for medium water, the state 0 is the resting state (downstream) and the state 1 is the state behind the primary shock wave that propagates through the water (upstream). The acoustic impedance Z of a medium is defined by relation (10):…”

“…The spray formation depends greatly on the flow characteristics at the nozzle orifice outlet, such as the turbulence energy and velocity distribution. The presence of cavitation within an orifice can also enhance the spray characteristics [ 6 , 7 , 8 , 9 , 10 ]. Some medical therapies take advantage of the mechanical impact of inertial cavitation, such as thromboltic therapy [ 11 , 12 ] and shock wave lithotripsy (SWL) [ 13 , 14 , 15 , 16 , 17 , 18 ].…”