Andrey V. Shalunov

Multifrequency ultrasonic transducer with stepped-plate disk

In article are suggest multifrequency ultrasonic transducer with stepped-plate disk. This device is mean for coagulation aerosols with 0.4 µm particle size. Also present method of engineering calculation stepped-plate radiator.

Ultrasonic radiators for the action on gaseous media at high temperatures

The article is devoted to the study of influence of high temperature on the operation of the ultrasonic disk radiator intended for generation of high-intensity vibrations in gaseous media. As a result of researches it was determined, that temperature increase of gas and the radiator led to the rise of vibration amplitude of the surface of the disk radiator and the fall of level of acoustic pressure owing to the reduction of gas density.

The acoustical coagulation of aerosols

Modern tendencies of society development, which are connected with wide spread of potentially dangerous manufactures and constantly appearing terroristic threats. The danger is concerned with spraying of toxicants in places with crowds of people, so it is necessary to create effective devices for aerosol neutralizing. This article is devoted to designing of such equipment.

Increase of separation efficiency in the inertial gas-purifying equipment by high-intensity ultrasonic vibrations

This article describes the prospects of applying of ultrasonic vibrations to increase efficiency of gas-dispersed flow separation on the example of the vortex tube. Developed model of the separation of gas-dispersed flow containing solid particles is described. The specific feature of the model is in consideration of particle coagulation caused by high-intensity ultrasonic vibrations. The characteristics of the gas flow and ultrasonic influence providing minimum separation time of solid fine particles and continuous phase are determined.

Theoretical study of acoustic coagulation of gas-dispersed systems

The mathematical model of the process on the macroscopic level considering viscosity of gas medium has been proposed for the analysis of acoustic coagulation of solid and fluid particles in gas media. The article presents the results of theoretical calculations, which allow determining the dependences of coagulation velocity at the different initial particle concentration on the parameters of acoustic influence (intensity, frequency). As a result of the investigation high efficiency of application of acoustic vibrations with the frequencies lying in the ultrasonic range for coagulation of fine aerosol (up to 5 µm) is shown.

Ultrasonic oscillating system for radiators of gas media

In article the new construction of the multiple-unit piezoelectric transducer with the increased output power and a disk radiator, which has a refined thermal mode is offered. The designing procedure of bending vibration disk radiators is described. The developed constructions are implemented; their technical characteristics and functionality are explored.

Designing of multi-frequency source of ultrasonic action with radiator in form of stair-step disc

The article is devoted to designing of multi-frequency source of ultrasonic action with radiator in form of stair-step disc.

Method of analysis of ultrasonic radiators on the base of flexural vibrations of disks with step-variable form

In the article method of analysis of parameters of disk radiators of step-variable form according to requirements of technological process and geometric sizes of the disk is described.

Determination of ultrasonic effect mode providing formation of cavitation area in high-viscous and non-Newtonian liquids

The article presents the phenomenological model of the formation of cavitation area in high-viscous and non-Newtonian liquids. Proposed model is based on the study of the formation of cavitation area as a whole but taking into account the main effects and phenomena occurring inside this area. The analysis of the model allows revealing optimum intensities of the ultrasonic influence, which are necessary for the appearance of the mode of developed cavitation for liquids different in their rheological properties. The analysis of the model lets determining, that optimum intensities of the influence for the most of liquids does not exceed 40 W/cm2 at the frequency of 22 kHz, with the exception of dilatant fluids, for which intensity of influence can achieve 100 W/cm2. As a result of the model analysis it is found out the change of optimum intensity for non-Newtonian liquids with the course of time induced by the relaxation of viscosity. Increase or decrease of the intensity, which is necessary for the formation of cavitation area, achieves 20 W/cm2. Obtained results can be applied for the choice of power modes of the ultrasonic technological equipment and the control of the process of cavitation treatment of media with different rheological properties.

The control of the ultrasonic coagulation of dispersed nanoscale particles

In the article the results of the researches on efficiency definition of ultrasonic coagulation of ready nanodispersed product are presente. Developed measuring bench allowed to control changes of concentration of nanoparticles due to their agglomeration at the application of high-intensity ultrasonic vibrations.