The preparation of fine, uniform, and stable emulsions and suspensions is a topical problem, which exists today in many branches of industry such as the oil industry, heat and power engineering, chemicals, mechanical engineering, agriculture, building, ecology, and food. The existing methods either do not pro vide the necessary dispersity of the product, or they have high power consumption with low productivity.Currently, the mixing generators, which implement the cavitation phenomena, are recognized to be promising facilities for obtaining finely dispersed and highly stable uniform emulsions [1]. The hydrody namic flow generators play an important role in wave technology, which is based on the excitation of non linear vibrations in multiphase media. Among the flow generators, the wave generators, in flat profiled channels, in which the flow bodies of various geometries are installed, occupy a special place. In these generators, in order to excite high power oscillations and waves in the treated media, high turbulent tear vortex flows, as well as extended cavitation regions, are used [2][3][4]. In such generators, the oscillations are excited by the passed flow, i.e., the treated medium simultaneously serves as the working medium for the generators.The questions of the appearance and the development of the cavitation in multiphase systems in the presence of the influence of wave fields on these processes, the turbulence and vorticity levels of the flow, as well as the geometry of flow bodies, which determines the character of the flow detachment from the surface of these bodies, are described in some theoretical and experimental studies [5][6][7][8][9][10][11][12][13]. The analysis of these materials showed that in order to construct the actual flow patterns in the flow type flat generator with various flow bodies, and to develop the improved physical and mathematical models, the calculated and experimental data available in publications are insufficient.This article is the continuation of the conventional investigations performed at the Scientific Center YUSHKOV et al. CONCLUSIONSThe formation of holes on the surface of the working channel along with notching on the surface of the flow body substantially improves the quality of the emulsion formed. In this case, the highest mixing effi ciency in a flat generator is attained upon installing the single row of bodies in the form of a single cylinder.An increase in the viscosity of the additional component when forming the water-oil emulsion leads to an increase in the concentration of smaller drops, the value of which reaches 88% and 96% for drops smaller than 3 µm and 5 µm, respectively.
The scientific formulation of the problems of non linear wave mechanics of multiphase systems includ ing the cavitation phenomena in wave fields arose due to inquiries of practice and the necessities of the petro leum industry, thermal power engineering, chemical industry, mechanical engineering, agriculture, civil engineering, ecology, and the food industry. The pri mary role in the wave technology based on the excita tion of nonlinear vibrations in multiphase media is the formation of scientific fundamentals of designing wave machines and mechanisms [1][2][3]. In the wave tech nology, the flowing wave generators occupy an appre ciable place in plane profile channels in which vari ous shape obstacles are established. In these genera tors, vortical highly turbulent detached fluid flows and extensive regions of developed cavitation are used for exciting powerful vibrations and waves in treated media. The complex character and features of the hydrodynamic processes proceeding in flowing chan nels of this type of generators and the absence of suffi cient data on the flow patterns complicate obtaining authentic data in calculations.In this study, we presented experimental data on the features of fluid flow in flowing plane wave generators, the base fundamentals of which are given in [1][2][3].We investigated the model of the generator repre senting a plane channel of variable cross section with aerodynamic bodies: cylinder, plate, sickle, and glass, the principal scheme of which is shown in Fig. 1.The tests were carried out at the hydrodynamic stand St 3 of the Research Center of Nonlinear Wave Mechanics and Technology of the Russian Academy of Sciences. As a working body, we used tap water at t = 20°C. The pressure at the generator input varied in the range P in = 0.12-1.0 MPa, and the pressure at its out put was Р out = 0.l4-0.8 MPa. The Reynolds number Re varied in the range of 8 × 10 3 -2.2 × 10 5 , where we accepted the obstacle transverse size d for the linear size and the incident flow velocity for the velocity V inc . The highest flow velocity before obstacles amounted to V inc = 20 m/s. For measuring the pressure pulsations behind the aerodynamic bodies, we flush mounted a piezoelectric pressure gauge Kistler 701K at the inner channel sur face. The obtained data were detected and processed on a LeCroy and Gould digital oscillograph.The initiation and development of the cavitation process were investigated with the help of optical visu alization of the cavitation regions saturated with gas bubbles. In this case, one of the channel walls was made from transparent Plexiglas, and another wall was covered with black matte paint. The light beam from the optical illumination directed under a certain angle with respect to the fluid flow was reflected by gas bub bles and singled them out from the water flow mass. The visualized patterns of the formation and develop ment of cavitation zones in the flow were detected with the help of a digital camera and a high velocity camera Citius Imagine C10 with the possibility to...
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