Using acoustic field energy to decrease dust discharge from the working space of the Vanyukov furnace

Results of the experimental studies of the subsonic round and plane both the macro and micro-jets are reported. The new phenomenon associated with transformation of the round micro-jets into the plane micro-jets under effect of a transversal acoustic field is revealed. It is shown, that its downstream development is determined by the sinusoidal instability mechanism of the plane jet. The disintegration phenomenon of the micro-jets on two jets developing separately from each other is revealed. It is found, that two new micro-jets are spreaded under a definite angle to each other and subjected by high-frequency secondary instability. It is shown, that sinusoidal instability of a plane jet is saved for macro and microjets both with acoustic and without acoustic effect. It is found, that the pseudo plane micro-jet at the presence of an acoustic field demonstrates presence in it of the vortex structures and dependence of the jet splitting angle from the frequency acoustic. The new phenomenon, so-called twist of a plane of a micro-jet on its edges in direction of the stream velocity vector created by a transversal acoustic field is revealed. It is shown, that process of the micro-jet twist result in a stupor of the jet downstream development and delay of its turbulisation. It is found, that sinusoidal instability of the round microjet depends on a direction of the acoustic field vector while the plane micro-jet does not depend. It is shown, that the new phenomena detected during investigations of a development both the round and plane micro-jet are stipulated by commensurability of the transversal acoustic field energy with the micro-jets energy.

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Application of partial areas method in the problem of sound radiation by a sphere in a waveguide with soft acoustically boundaries

Eastern-European Journal of Enterprise Technologies ◽

10.15587/1729-4061.2021.243161 ◽

2021 ◽

Vol 5 (5 (113)) ◽

pp. 62-79

Author(s):

Oleksii Korzhyk ◽

Sergey Naida ◽

Tetiana Zheliaskova ◽

Oleksander Chaika ◽

Nikita Naida

Keyword(s):

Boundary Conditions ◽

Acoustic Field ◽

Practical Importance ◽

Experimental Studies ◽

Fourier Method ◽

Liouville Problem ◽

Source Surface ◽

Sound Waves ◽

Spherical Source ◽

Working Space

The paper considers the features of the formation of an acoustic field by a spherical source with complicated properties in a regular plane-parallel waveguide, which is of practical importance in marine instrumentation and oceanographic research. The calculation algorithm is based on the use of the Helmholtz equation and the Fourier method for each partial region and the conjugation conditions on their boundaries. The presented calculation allows one to get rid of the idealized boundary conditions on the source surface, with the subsequent determination of the excitation coefficients of the waveguide modes within the framework of the Sturm-Liouville problem. In this case, the attraction of the boundary conditions on the surface and the bottom of the sea, as well as the Sommerfeld conditions, makes it possible to obtain the real distribution of the field in the vertical sections of the waveguide. The obtained frequency dependences of the pressure and vibrational velocity components show their amplitude-phase differences, which reach 90 degrees, which partially explains the appearance of singular points in the intensity field in a regular waveguide. It has been determined that multiple reflections of sound waves from the boundaries of the working space and the space of the waveguide cause oscillations of the pressure components with a change in the amplitude level up to 6 dB. It was found that with an increase in the size of the source, a kind of resonance is formed in the working space, the frequency of which depends on the depth of the sea and corresponds to the region kr=x=5.8. It was found that when the acoustic field is formed in the working space, the frequency response of the impedance components is represented as a multiresonant dependence formed on the basis of the frequency characteristics of the lower modes and their combinations. Experimental studies have shown that the results of calculations of the mode composition of the acoustic field of the emitter, obtained in the conditions of the pool, correspond to the spatial characteristics of the mode components of the acoustic field with an error of up to 3 dB

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Utilization of Acoustic Field Energy for Reduction of Dust Discharge in High-Temperature Furnaces

KnE Materials Science ◽

10.18502/kms.v6i1.8103 ◽

2020 ◽

Author(s):

V.I. Matyukhin ◽

O.V. Matyukhin ◽

M.A. Putilov ◽

A.T. Ermekova

Keyword(s):

High Temperature ◽

Acoustic Field ◽

Field Energy ◽

Theoretical Justification ◽

Total Dust ◽

Industrial Implementation ◽

High Temperature Furnaces ◽

Dust Precipitation

In order to reduce the total dust discharge from high-temperature furnaces, this study advocates the use of the energy of the acoustic field formed in the furnace body with application of acoustic generators of Hartmann whistle type. The paper provides theoretical justification of dust precipitation inside the furnace and develops principles of its implementation. The efficiency of this method is shown by examples of industrial implementation. Keywords: dust precipitation inside the furnace, acoustic field energy, Hartmann whistle

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