RU1796838C - Chimney stack - Google Patents

Abstract

Usage: increase the height of the emission of flue gases into the atmosphere. SUMMARY OF THE INVENTION: the device comprises a barrel, a source of acoustic vibrations in the form of Rijke pipes mounted vertically around the perimeter of its cross section and including a thin-walled cylinder made of heat-resistant material, a heating element. Acoustic vibrations are generated in the Rijke pipes corresponding to the maximum sound pressure on the axis of the flue gas flow, which act on the annular vortices, reducing turbulence and increasing the range of the flue gas stream. 2 ill.

Description

The invention relates to devices for the emission of flue gases into the atmosphere and is intended to protect the environment from pollution by harmful emissions.

A device for burning fuel is known, comprising a housing made in the form of a cylinder open on both sides with a grate located in its lower part.

The closest solution is a chimney containing a housing and acoustic emitters mounted on a pipe section.

The disadvantages of this device are the fragility of the acoustic emitters and the inability to completely irradiate the smoke stream with acoustic emitters located outside the jet itself.

The purpose of the invention is to increase the height of the emission of flue gases into the atmosphere.

This goal is achieved in that the acoustic device comprises a chimney and a source of acoustic vibrations made in the form of Rijke pipes mounted vertically around the perimeter

cross section inside the chimney into one or more horizontal rows at its section.

In FIG. 1. 2 schematically shows the proposed device.

The acoustic device comprises a chimney barrel 1 and a source of acoustic vibrations located inside the chimney pipe and made in the form of Rijke 2 pipes mounted vertically along the perimeter of the cross section of the chimney barrel 1 in one or more horizontal rows. Each Rijke pipe 2 is a thin-walled cylinder 3 made of heat-resistant material (e.g. asbestos), open from both ends, having a heating element 4 on its inner surface, installed one quarter of the length of cylinder 3 from its lower end. As a heating element 4, for example, an annular wire electric spiral can be used, which has a large ohmic resistance and is connected together with other heating elements of other tpy6

With

with

Xj

h

about

00 GO 00

Rijke to the source of electric current, The length of the Rijke pipes and their diameter are selected from the working conditions of the device.

The device operates as follows.

When flue gases are supplied to the chimney barrel 1 by a sensor signal (not shown in Fig.), The heating elements 4 in the Rijk 2 pipes are turned on. Due to self-oscillating processes occurring in the Rijke 2 pipes, acoustic oscillations of a certain frequency are generated in them, depending on the length of the Rijke pipe . For identical lengths of Rijke 2 pipes, the source of acoustic oscillations generates monotonous sound of a certain frequency, the sound pressure level of which depends on the diameter of the Rijke pipes and on their total number. The frequency of sound should correspond to a certain range of values of the numbers of Struhal:

Sh., 5 ,:

where f is the frequency of sound, Hz;

D is the diameter of the pipe trunk at its section,

m; ..

V-cKopocTb flue gas at the cut of the chimney barrel, m

0

The value of the sound pressure of the source of acoustic vibrations must correspond to the maximum value of the sound pressure on the axis of the flue gas stream at the cut of the chimney barrel 1. When flue gases flow out of the chimney, ring vortices arise at its cut, which interact with each other. Acoustic vibrations act on these vortices, reducing the turbulence of the flue gas jet and, consequently, increasing its range.

The technical and economic efficiency of the device is caused by an increase in the height of the emission of flue gases into the atmosphere, which leads to a decrease in the surface concentration of harmful substances in the emission region, an increase in the durability of the source of acoustic vibrations compared to the prototype, which gives the effect of saving material and money, as well as a decrease pipe heights due to more complete irradiation of the flue gas stream and, consequently, a greater increase in the range of the pipe, which also gives the effect of saving material x and cash.

Claims (1)

The formula was also invented by the Smoke tube containing a barrel and a source of acoustic vibrations, characterized in that, in order to increase the height of the flue gas emission into the atmosphere, the source of acoustic vibrations is made in the form of Rijke tubes installed vertically along the perimeter of the cross section inside the barrel in one or several horizontal rows at its slice. fi g 2