RU72514U1 - AXIAL MULTI-STAGE COMPRESSOR - Google Patents

Abstract

The compressor with increased efficiency due to the uniform distribution of the injected water in the air stream is designed to compress air and is used in engine building. An axial multistage compressor comprises a housing with a spatula placed in it with steps, each of which includes working and guide vanes. Along the perimeter of the casing behind the working blades in front of the channels formed by adjacent guide vanes of at least one stage, at least two means for jet injection of water into the air stream are radially installed. Each of the means for injecting water has a flow channel and an outlet channel communicating with it located at an angle of 110 to 180 degrees to it, oriented in a direction companion to the air flow, defined by the location and shape of the guide vanes. The flow channel is connected to the tank with water and a pump through a manifold with a pipeline and shutoff valves. At the same time, the water flow rate and the orientation angle of the outlet channel, different for each of the water injection means located in one stage, should together provide a substantially uniform distribution of water along the height of the blades of the next stage. Means for injecting water can be additionally installed in front of the scapular apparatus. Means for jet injection of water are installed in the compressor casing in such a way that they protrude into the casing by a minimum amount from the condition of their placement.

4 ill.

Description

The utility model relates to the field of energy, in particular to gas turbine engine building, and can be used in other sectors of the economy where devices for compressing and supplying air are used, for example, in the field of aircraft engine building.

Known axial multistage compressors comprising a housing with an internal cavity in which a blade apparatus with steps is located, each of which includes a working blade and a guide blade. In front of the scapular apparatus, hollow racks with holes or nozzles for water injection are installed, connected by a pipeline to a tank with water through a pump and a manifold. [“Test results of the compressor of the MES-60 installation with water injection into the flow part”; Belyaev V.E., Sereda S.O., Gelmedov F.Sh., Muntyanov I.G., Muntyanov G.L., Gas turbine technologies, 2005, N 4, p.16-20.]. Water injection in front of the scapula reduces the power spent on the compressor drive by 2 ... 4%.

However, the filling of the air flow with water droplets occurs unevenly in its volume, and due to the separation of water on the compressor casing, the amount of evaporated water in relation to the flow rate of the injected water decreases. As a result, the process of compression of the main amount of air in the compressor occurs without sufficient evaporative cooling, which negatively affects the increase in compressor efficiency. In addition, the injection in front of the scapular apparatus does not completely wash out the surface of all compressor blades from deposits. At the same time, the erosion and vibration hazard for compressor blades increases.

Known injection desuperheater [patent RU No. 2206822, F22G 5/12, published 20.06.03], designed to cool the steam stream by injection of water into it. The injection is carried out using a water nozzle with a nozzle at the outlet end

through the hole in the wall of the casing of the steam pipe to a minimum value from the condition of the possibility of placing the nozzle. The nozzle is oriented in a satellite direction at an angle to the steam stream. Water is sawn by a nozzle and enters the steam stream, cooling it to the desired temperature.

Using the specified device in the compressor will not allow evenly filling the air flow with water droplets, as a result of which its evaporation will worsen and, accordingly, the efficiency of the compressor. Also, due to the uneven distribution of water in the air stream, the surface of the compressor blades cannot be completely washed away from deposits and there is a risk of erosion and vibration of the blades due to excessive local water concentration.

A compressor is known [patent RU No. 2261351, F02C 9/00, published 2005.09.27], in the inlet channel of which nozzles are evenly arranged around its circumference, to which water is supplied through the manifolds through pipelines from the tank. The necessary water pressure and its flow rate are created by the pump. The amount of injected water is within 1 ... 3% of the air flow through the compressor.

Injecting water into the air stream in the inlet of this compressor increases the degree of pressure increase. However, when nozzles are installed in front of the compressor vanes, water drops do not penetrate the air stream to a sufficient depth, as a result of which the injected water is distributed unevenly in the air stream and evaporates worse. As a result, the energy consumption for the compressor drive increases and the efficiency of the compressor decreases.

Closest to the proposed compressor is a multi-stage axial vane compressor [patent RU No. 2055997, F02875 / 12, F02G 3/00, F02B 37/00, published 10.03.96], equipped with means for the injection and spraying of water installed in the inlet channel and between compressor steps. Water is sprayed by direct-jet or centrifugal nozzles to finely dispersed

state, due to which the compression is isothermal. The fine atomization is ensured by a high pressure (20 ... 50 MPa) of water created by the pump and a small passage section of nozzle openings (0.1 ... 0.8 mm). For reliable and economical operation of the compressor stages, it is necessary to repeatedly inject water into the stages while maintaining the specific water flow rate for compression unchanged.

The disadvantages of the known compressor include the following. Firstly, when installing nozzles in front of the compressor stage, water immediately enters the rotating working blades, separates on them and is discarded by centrifugal forces onto the compressor casing. As a result, drops of injected water cannot be evenly distributed in the air stream. Secondly, with a finely dispersed spray of water, small droplets quickly acquire a speed close to the speed of the air flow, and do not penetrate the air stream to a sufficient depth.

Due to the uneven filling of the air flow with water drops, the compressor efficiency does not increase, and their excessive local concentration causes erosion and vibration of the blades, as well as incomplete washing of the surface of the blades from deposits.

The task to which the claimed utility model is directed is to develop a simple to manufacture design of an axial multistage compressor with increased efficiency by ensuring uniform distribution of water in the air stream. In this case, complete washing of the surface of the compressor blades from deposits and salts is also achieved.

The essence of the invention is as follows. An axial multistage compressor comprises a housing with a blade apparatus located in it, consisting of steps, each of which includes working and guide vanes. Similar to the prototype, the compressor is equipped with a means for injecting water. Unlike the prototype, along the perimeter of the compressor casing behind the blades in front of the channels formed

adjacent guide vanes of at least one stage are radially mounted with at least two means for jet injection of water into the air stream. Each of the means for injecting water has a flow channel and an outlet channel communicating with it located at an angle of 110 to 180 degrees to it, oriented in a direction companion to the air flow, defined by the location and shape of the guide vanes. The flow channel is connected to the tank with water and a pump through a manifold with a pipeline and shutoff valves. At the same time, the water flow rate and the orientation angle of the outlet channel, different for each of the water injection means located in one stage, should together provide a substantially uniform distribution of water along the height of the blades of the next stage.

In the particular case of the implementation of the compressor, means for injecting water can also be installed in front of the scapular apparatus.

Means for jet injection of water are installed in the compressor housing in such a way that they can protrude into the housing by a minimum amount from the condition that they can be placed with the necessary orientation of the exhaust channel in order to prevent aerodynamic disturbances in the air flow during compressor operation.

The proposed compressor design allows you to optimize the water injection into the compressor, that is, it makes it possible to inject water in several stages simultaneously. Optimized injection improves compressor efficiency to a much greater extent than single-stage injection. With such an injection, water in the compressor stage is added as it evaporates in the air stream, as a result of which the amount of evaporated water increases and the energy loss for water advancement in the compressor blade apparatus decreases.

Jet water injection is carried out in order to penetrate the jets into the air stream to a depth sufficient for even distribution of water.

When installing means for injecting water behind the working blades in front of the channels formed by adjacent guide vanes, after the injection, water jets pass through the air flow between the guide vanes of the stage and collide with the working blades of the next stage. The jets of water form a film of water on these blades, which moves under the influence of an air stream. During the flow of the film on the surface of the working blades as a result of rotation of the latter, water is distributed evenly in the circumferential direction. This uniformity promotes intensive evaporation of water, greater cooling of the air, and, as a consequence, an increase in efficiency. Eliminating the uneven distribution of moisture in the flow reduces the risk of blade erosion and vibration. A more complete flushing of the surface of the blades reduces the friction loss of the flow on the blades.

For uniform filling of the air flow with water along the height of the blades, it is necessary to use at least two means for jet injection of water,

differing in the orientation angle of the outlet channel relative to the flow channel. In this case, it is advisable to install the tools around the perimeter

the compressor casing at a certain distance from each other in the circumferential direction, then the impact of the working blades with the jets will not occur simultaneously, as a result of which the vibration hazard for the blades will be reduced.

The water supply to each means for water jet injection of water through the collector and the presence of shut-off valves makes it possible to control the total flow rate of water injected into the compressor stage, depending on the number of included means for water injection.

The orientation angle of the outlet channel of each means for water injection is calculated from the condition that the jet flowing from it reaches the next stage working blade at a certain height, and the water flow rate ensures uniform distribution of water over the surface of the blade. The water flow rate is controlled by valves, depending on the amount of means for water injection and on the diameter of the channel. The ratio

between the depth of penetration of water jets into the air stream, the angle of the jet orientation, the air and water velocity, and the diameter of the jet are known and can be calculated, for example, using the formulas given in the book “Physical fundamentals of the working process in the combustion chambers of air-jet engines”. Authors: Rauschenbach et al. M., "Mechanical Engineering", 1964., 526.

According to calculations, when the orientation angle of the outlet channel of the water injection means relative to the oriented radially flow channel is less than 110 degrees, water practically does not penetrate deep into the air flow, as a result of which the compressor efficiency decreases. The maximum penetration depth of the injected water into the air stream is achieved at 180 degrees, that is, perpendicular to the compressor housing. When the jet flows towards the air stream, that is, if the angle is more than 180 degrees, water droplets will fall on the working blades of the stage, break them, and will not penetrate deep into the air stream.

Since under the action of centrifugal forces water is separated on the compressor housing, zones where water is absent can form. Typically, these zones are located in the root sections of the shoulder blades. The proposed compressor design allows for additional injection of water into such zones from water injection means, the outlet channels of which are oriented to the root sections of the blades. At the same time, it is possible to avoid introducing excess amounts of water into the stage, rinse the surface of the blades from deposits and salts and increase the efficiency.

Complete washing of the surface of the compressor blades from deposits and salts increases the efficiency of the compressor by reducing aerodynamic resistance to air flow.

The essence of the utility model is illustrated by the following graphic materials, which depict:

Figure 1 - General view of the compressor with two means of water injection in front of the scapula and with four means of water injection in the third stage - a special case of the implementation of the proposed utility model;

Figure 2 is a transverse section aa of the compressor;

Figure 3 - layout of the means for water injection in the compressor housing;

Figure 4 - the paths of the jets along the height of the blades for a particular case of the implementation of the proposed utility model when installing four means for injecting water into the 3rd stage of the compressor of the gas turbine installation GTK-10-4.

In the particular case of implementation, the compressor (Fig. 1) comprises a housing 1, with a blade apparatus 2 located therein, consisting of four stages 3, 4, 5, 6, each of which includes rotating working blades 7 and fixed guide vanes fixed to the housing 1 8. Two means for injecting water 9, 10 are radially mounted around the perimeter of the housing 1 in front of the scapular apparatus 2, and four means 11, 12, 13, 14 for jet injection of water into the stream are radially mounted behind the working blades 7 in front of the guide blades 8 of the third stage 5 air (figure 2). To this end, openings are made in the housing 1 opposite the channels formed by adjacent guide vanes 8. Each of the means 11, 12, 13, 14 for supplying water has a flow channel 15 and an outlet channel 16. The axis of the channel 16 is located for each means 11, 12, 13 , 14 at different angles β in the range from 110 to 180 degrees to the axis of the flow channel 15 and is oriented in a direction that is confined to the air flow, which is defined by adjacent guide vanes 8 (Fig. 3). Means 11, 12, 13, 14 are installed inside the compressor housing 1 (Fig. 3) by the minimum value from the condition that they can be placed, namely, by the amount necessary to orient the exhaust channel. In the particular case of the compressor in the tool 11, the channel 16 is made at an angle of 110 degrees, in the tool 12 - at an angle of 135 degrees, in the tool 13 - at an angle of 165 degrees, in the tool 14 - at an angle of 180 degrees. Each of the means 11, 12, 13, 14 is connected to the tank

17 with water and a pump 18 through a manifold 19 with a pipe 20 and shutoff valves 21 for the possibility of regulating the flow of water depending on the number of means 11, 12, 13, 14 included by means of shutoff valves 21 to ensure a substantially uniform distribution of water along the height of the working blades 7 steps 6.

The compressor operates as follows.

Air enters the compressor housing 1 for compression (FIG. 1). The air flow in each stage 3,4, 5, 6 first passes through the working blades 7 and then through the guide vanes 8. Through pipelines 20 (figure 2) water is supplied to the means 9, 10, 11, 12, 13, 14. The jets water flowing from the channels 16, fall into the air stream between the guide vanes 8 and move along the surface of the guide vanes 8. The jets pass along the air flow until they collide with the working vanes 7 of the next stage 6 of the compressor. Due to the separation of water jets on the blades 7 and the rotation of the latter, the water is distributed uniformly in the circumferential direction. When using means 9, 10, 11, 12, 13, 14 with different orientation angles of the outlet channels, the water is distributed uniformly as a whole, over the entire air flow in the compressor, which significantly increases the efficiency. In addition, due to the distribution of several means for water injection in one stage in different places around the circumference of the compressor casing, the impact of water with the blades is less rigid, as a result of which the vibration hazard of their operation is reduced.

The proposed compressor has a greater value of efficiency, which is due to the possibility of a uniform volume of air flow of water injection into various stages of the compressor. The utility model is relatively simple and in a short time can be implemented in commonly used compressors.

In accordance with the claimed design on the basis of the compressor of the gas turbine installation GTK-10-4, a working draft was completed

proposed compressor. Means for water injection were installed in the compressor housing in front of the scapular apparatus and in front of the guide vanes of the third and seventh stages, 4 means in each case. The angles β were chosen equal to 110, 135, 165, and 180 degrees, respectively. At the same time, water jets when they passed the distance between the guide vanes reached the subsequent working vanes uniformly in height. Figure 4 shows the trajectory of the jets during the injection of water into the third stage of the compressor of the gas turbine installation GTK-10-4. X coordinate is directed in the direction of air flow, Y coordinate - along the height of the blades. The paths of the jets arising from the means 11, 12, 13, 14 are indicated in Fig. 4 by numbers corresponding to these means.

As a result of using the proposed utility model, the efficiency of the compressor compared to the original compressor increased by 3.2%. At the same time, the useful power and efficiency of the GTK-10-4 installation increased by 16% and 3.5% relative, respectively.

Claims (3)

1. An axial multistage compressor comprising a housing with a spatula placed in it with steps, each of which includes working and guide vanes, along the perimeter of the housing behind the working vanes in front of the channels formed by adjacent guide vanes of at least one stage, at least radially mounted than two means for jet injection of water into the air stream, each of which has a flow channel and located at an angle from 110 to 180 ° to it, the outlet channel communicating with it, oriented in In the direction to the air flow, the flow channel is connected to the tank with water and the pump through a manifold with a pipeline and shutoff valves, while the water flow rate and the orientation angle of the outlet channel, different for each of the water injection means located in one stage, must together to provide a substantially uniform distribution of water along the height of the blades of the next stage. 2. The compressor according to claim 1, characterized in that the means for injecting water are installed in front of the scapular apparatus. 3. The compressor according to claim 1 or 2, characterized in that the means for jet injection of water are installed in the compressor casing in such a way that they protrude into the casing by a minimum amount from the condition of their placement.