CN115875134A - Gas turbine bleed air mixing nozzle and noise elimination method - Google Patents

Abstract

The invention relates to the field of gas turbines, and discloses a gas turbine bleed air mixing nozzle and a noise elimination method. The invention solves the problem of high noise pollution of the gas turbine in the prior art.

Description

Gas turbine bleed air mixing nozzle and noise elimination method

technical field

The invention relates to the field of gas turbines, in particular to a gas turbine bleed air mixing nozzle and a noise reduction method.

Background technique

The gas turbine is an internal combustion power machine that uses continuous flowing gas as the working medium to drive the impeller to rotate at high speed, and converts the energy of the fuel into useful work. It is a rotary impeller engine. The noise generated during the operation of the gas turbine is mainly divided into three categories: the noise generated during the operation of the equipment, the magnetic field noise and the air noise. Among them, the air noise is mainly generated during the intake of the gas turbine and the ventilation of the main and auxiliary machines. When the anti-icing system of the gas turbine is working, the hot air drawn from the compressor will also produce obvious aerodynamic noise due to its high speed and high pressure.

The Chinese invention patent with the publication number CN111058947A discloses a gas turbine exhaust utilization system. The technical problem solved by the exhaust utilization system is that the exhaust velocity of the gas turbine is high, which is a waste of kinetic energy and has high noise pollution. The technical solution of the present invention is to obtain the sound-absorbing effect through the arrangement of the air passage and the arrangement of the sound-absorbing cotton, but there is a problem that the sound-absorbing effect is not ideal.

Contents of the invention

In order to solve the problem of high noise pollution of gas turbines in the prior art, the invention provides a gas turbine bleed air mixing nozzle and a noise reduction method.

The specific scheme adopted by the present invention is: a gas turbine bleed air mixing nozzle, an air inlet pipe is arranged in the nozzle body, one end of the air inlet pipe is connected to the base, and a first through hole is arranged on the pipe wall of the air inlet pipe, so that A plurality of baffles are arranged outside the intake pipe, and the space outside the intake pipe is divided into a plurality of chambers by the baffles, one of the baffles is located on the same level as the end of the intake pipe, and the second baffle is arranged on the baffle. Ventilation holes, a plurality of air outlets are arranged on the upper side wall of the nozzle body.

A cover plate is provided at the end of the base.

The number of the baffles is 4, and the space outside the inlet pipe and the nozzle body is divided into a first expansion chamber, a second expansion chamber, a first damping layer, and a second damping layer from bottom to top. Damping materials are arranged in the first damping layer and the second damping layer.

The baffle is an annular plate, and the inner diameter of the annular plate is adapted to the outer diameter of the intake pipe.

The distance between the end of the air inlet pipe and the top of the nozzle body is 1/4 of the length of the nozzle body.

The base of the nozzle is connected with the bleed air pipeline.

On the other hand, the present invention provides a kind of gas turbine bleed air blending noise reduction method, comprising the following steps:

(1) Install the noise-absorbing nozzle;

(2) Carrying out compound anti-type noise reduction, the gas enters the relatively independent chamber of the lower floor through the first through hole provided on the air intake pipe to perform composite anti-type noise reduction;

(3) Carrying out compound resistance type noise reduction, gas enters the relatively independent chamber of the upper layer through the first through hole provided on the air intake pipe to perform compound resistance type noise reduction;

(4) The gas is discharged through the air outlet.

Compared with the prior art, the present invention has the following beneficial effects:

The invention provides a gas turbine bleed air mixing nozzle. An air inlet pipe is arranged in the nozzle body, and one end of the air inlet pipe is connected to a base. A first through hole is arranged on the pipe wall of the air inlet pipe. A plurality of baffles are arranged outside the air inlet pipe. The baffles will The space outside the intake pipe is divided into a plurality of chambers, one of the baffles is located on the same level as the end of the intake pipe, a second air hole is arranged on the baffle, and a plurality of outlets are arranged on the upper side wall of the nozzle body. stomata. The present invention uses baffles to divide the space outside the air inlet pipe and inside the nozzle pipe into different relatively independent chambers, and uses the through holes provided on the outer wall of the air inlet pipe to introduce gas into different chambers, so that the present invention is aimed at low and low The mids, mids, and treble all feature noise canceling, and the noise reduction effect on the gas turbine is remarkable.

In the present invention, the space outside the air intake pipe and inside the nozzle body is divided from bottom to top into a first expansion chamber, a second expansion chamber, a first damping layer, and a second damping layer. The first damping layer, the second damping layer The damping material is arranged in the layer. The first expansion chamber and the second expansion chamber in the present invention can not only effectively reduce noise, but also buffer the gas to a certain extent, reducing the harm caused by excessive instantaneous pressure.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the schematic diagram of air outlet among the present invention;

Fig. 3 is the connection schematic diagram of intake pipe and base in the present invention;

4 is a schematic diagram of the first through hole in the present invention;

5 is a schematic diagram of a second through hole in the present invention;

Fig. 6 is a schematic diagram of a baffle without a second through hole in the present invention;

Fig. 7 is a schematic diagram of the installation position of the nozzle in the present invention.

Among them, the reference signs are respectively:

1. Compressor, 2. Combustion chamber, 3. Turbine, 4. Bleed air pipeline, 5. Muffling nozzle, 6. Nozzle body, 7. Intake pipe, 8. End cover, 9. Baffle, 10. First through hole, 11, first expansion chamber, 12, second expansion chamber, 13, first damping layer, 14, second damping layer, 15, base, 16, air outlet hole, 17, second through hole.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention is described below through specific embodiments shown in the accompanying drawings. It should be understood, however, that these descriptions are exemplary only and are not intended to limit the scope of the present invention. Also, in the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concept of the present invention.

In the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , or integrated; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediary, and it can be the internal communication of two components or the interaction relationship between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

The present invention provides a gas turbine bleed air mixing nozzle, the nozzle body 6 is provided with an air intake pipe 7, one end of the air intake pipe 7 is connected to a base 15, and a first through hole 10 is provided on the pipe wall of the air intake pipe 7 A plurality of baffles 9 are arranged outside the intake pipe 7, and the space outside the intake pipe 7 is divided into a plurality of chambers by the baffles 9, wherein one of the baffles 9 is located at the same level as the end of the intake pipe 7 The baffle plate 9 is provided with a second air hole 9 , and the upper side wall of the nozzle body 6 is provided with a plurality of air outlet holes 16 . A cover plate 8 is provided at the end of the base 15 . The number of the baffles 9 is four, and the space outside the inlet pipe 7 and the nozzle body 6 is divided into a first expansion chamber 11, a second expansion chamber 12, a first damping layer 13, The second damping layer 14, the first damping layer 13 and the second damping layer 14 are provided with damping material. The baffle plate 9 is an annular plate, and the inner diameter of the annular plate is adapted to the outer diameter of the intake pipe 7 . The distance between the end of the air inlet pipe 7 and the top of the nozzle body 6 is 1/4 of the length of the nozzle body 6 . The base 15 is connected with the bleed air pipeline 4 . The bleed air pipeline 4 is connected with the compressor 1 .

In the present invention, the air inlet pipe is inserted in the nozzle body, and around it, the first and second expansion chambers, and the first and second damping layers are blocked by the baffle plate according to the gas flow direction (from bottom to top). The first expansion chamber and the second expansion chamber realize the entry and exit of gas through the first through hole on the intake pipe. When the gas enters the first expansion chamber, the pressure is reduced by the mutual extrusion of gas molecules, and the mutual consumption is carried out to a certain extent. The noise reduction is mainly aimed at low-intermediate frequency and low-frequency noise. The gas enters the first damping layer after anti-neutralization. Since the material inside the first damping layer is a damping material, in one embodiment, the damping material is wire mesh, copper-zinc-aluminum alloy, It has a good noise reduction effect on noise. The second noise reduction has a certain buffering effect on the gas. The first damping layer is mainly for high-frequency noise, and then entering the second damping layer for noise reduction is mainly for middle layer noise. At the same time, the air outlet is arranged on the upper side wall of the nozzle body, which can also play a good role in noise reduction.

With reference to accompanying drawing, described air intake pipe stretches into nozzle pipe body, and exhaust hole is arranged on the body of air intake pipe to discharge gas, and described air intake pipe is in close contact with annular baffle plate, and one end of air intake pipe is connected with base (intake pipe The outer diameter of the pipe wall is less than the inner diameter of the base, and one end of the air inlet pipe is inserted into the base to realize the connection between the two), and the base is blocked by an end cover. One of the baffles is located at the same level as the end of the intake pipe, and a second ventilation hole is arranged on the baffle, that is, a second ventilation hole is opened on the top of the second damping layer for gas transportation. The diameter of the second ventilation hole ranges from 3 to 5mm, which is beneficial to the stable circulation of gas.

The present invention adopts the noise reduction method of resistive noise reduction and anti-type noise reduction at the same time, and has noise reduction function for low, low, middle, middle and high audio frequencies, and the gas entry with multiple audio frequencies can still play a good role in noise reduction. noise effect. The first and second expansion chambers in the present invention can not only effectively reduce noise, but also buffer the gas to a certain extent, reducing the harm caused by excessive instantaneous pressure. The size of the expansion chamber is determined according to the actual situation.

The invention provides a gas turbine bleed air blending noise reduction method, comprising the following steps: (1) installing the noise reduction nozzle; The hole enters the relatively independent chamber of the lower layer to perform compound resistance noise reduction; (3) performs compound resistance noise reduction, and the gas enters the relatively independent chamber of the upper layer through the first through hole set on the inlet pipe to perform compound resistance noise reduction. Acoustic; In steps (2) and (3), since the gas enters through the first through hole, the composite noise elimination through the micropore impedance is realized. (4) The gas is discharged through the air outlet. The present invention utilizes the noise reduction nozzle to first perform resistance type noise reduction and then resistive type noise reduction, and the mixed mode of the two solves the problem of high noise of the gas turbine.

In the present invention, the drawn high-pressure and high-temperature air flow is discharged through the uniform air outlet hole 16 after the complicated flow inside the nozzle. Only by the resistance effect, can all nozzles evenly spray hot gas for uniform mixing and achieve effective gas mixing.

The air outlet in the present invention has low-intermediate-frequency broadband noise reduction performance, relatively small (1-5mm) aperture can improve the sound absorption coefficient, low porosity can increase the width of the sound absorption frequency band, and the depth of the orifice plate can change the resonance sound absorption peak position. In order to ensure that the hot air can be evenly ejected from the nozzle, the total area of the air outlet holes is less than 80% of the cross-sectional area of the intake pipe. The invention realizes the uniform injection of hot air while reducing the noise generated by the gas turbine during operation.

The above drawings and explanations are only a specific embodiment of the present invention, but the specific scope of protection of the present invention is not limited to the above explanations, any technical ideas disclosed in the present invention, and simplified according to the technical solutions of the present invention All replacements or changes should be within the protection scope of the present invention.

Claims (7)

1. A gas turbine bleed air mixing nozzle is characterized in that, an air inlet pipe (7) is set in the nozzle body (6), and one end of the air inlet pipe (7) is connected with the base (15), and the air inlet pipe The first through hole (10) is set on the tube wall of (7), and a plurality of baffles (9) are arranged outside the air intake pipe (7), and the space outside the air intake pipe (7) is divided by the baffle plates (9). It is a plurality of chambers, wherein one of the baffles (9) is positioned at the same level as the end of the intake pipe (7), and the second vent (17) is arranged on the baffle (9), and the nozzle body ( 6) A plurality of air outlets (16) are arranged on the upper side wall. 2. The gas turbine bleed air mixing nozzle according to claim 1, characterized in that a cover plate (8) is provided at the end of the base (15). 3. gas turbine bleed air mixing nozzle according to claim 1, is characterized in that, the number of described baffle plate (9) is 4, and the outside of described inlet pipe (7) and nozzle body (6) The inner space is divided into a first expansion chamber (11), a second expansion chamber (12), a first damping layer (13), a second damping layer (14) from bottom to top, and the first damping layer (13), A damping material is arranged in the second damping layer (14). 4. gas turbine bleed air mixing nozzle according to claim 3, is characterized in that, described baffle plate (9) is annulus plate, and the inner diameter of described annulus plate is suitable for the outer diameter size of inlet pipe (7). match. 5. gas turbine bleed air mixing nozzle according to claim 4, is characterized in that, the distance of the end of described inlet pipe (7) from the top of nozzle body (6) is nozzle body (6) length a quarter. 6. The gas turbine bleed air mixing nozzle according to claim 5, characterized in that the base (15) is connected to the bleed air pipeline (4). 7. A gas turbine bleed air blending noise reduction method is characterized in that, said method is realized based on the gas turbine bleed air blending nozzle described in any one of claims 1-6, comprising the steps of: (1) Install the noise-absorbing nozzle; (2) Carrying out compound anti-type noise reduction, the gas enters the relatively independent chamber of the lower floor through the first through hole provided on the air intake pipe to perform composite anti-type noise reduction; (3) Carrying out compound resistance type noise reduction, gas enters the relatively independent chamber of the upper layer through the first through hole provided on the air intake pipe to perform compound resistance type noise reduction; (4) The gas is discharged through the air outlet.

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