RU2382885C2 - Nozzle vane of gas turbine with cyclone-swirler cooling system - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: nozzle vane of gas turbine with cyclone-swirler cooling system comprises swirling devices to cool cylindrical channels and leading edge perforation. Vane body has central hollow chamber to additionally feed coolant, via swirling devices arranged over height of cooling cylindrical channels at the distance equal to 4^th and 8^th gages referred to cooling channel diametre. Swirling matrix is arranged in vane trailing edge.

EFFECT: higher efficiency of cooling, longer life of vane.

4 cl, 8 dwg

Description

The invention relates to the field of engine engineering and can be used in the construction of cooled nozzle blades of gas turbines.

The invention improves the cooling efficiency, and therefore, increase the resource of the blade.

Known modern designs of cooled nozzle blades of a gas turbine with convective and convective-film cooling methods, having a channel-loop with numerous "strokes", a deflector, jet-deflector flow pattern of the refrigerant. Significant disadvantages of the known blades are: low cooling rate, significant refrigerant consumption, complexity and laboriousness of manufacturing deflectors (Bogomolov E.N. Workflows in cooled turbines of gas turbine engines with perforated vanes [Text] / E.N. Bogomolov - M. Machine-building, 1987 . - 160 p.).

The cooling process of the blades can be intensified by using swirling flows. Thus, cyclone-vortex (flow swirl) cooling systems can be proposed as alternative cooling schemes for gas turbine blades. The characteristic features of a swirling flow are most fully suited for creating effective schemes for convective and convective-film cooling systems for blades of a gas-turbine engine flow passage.

Closest to the technical nature of the claimed is a turbine blade using a vortex cooling system [US Patent No. US 6981846 F01D 5/18, Jan. 3. 2006], in the cavity of which two hollow chambers are made, from which the refrigerant enters into the cooling cells through swirling devices. The cooling cells are at least two cylindrical channels interconnected by twisting devices. The refrigerant from the hollow chambers enters the first cooling channel and exits through the side surfaces into the flow part through the last cooling channel of the cell. Part of the refrigerant from the central hollow chamber enters the channel of the inlet edge and enters the gas path through perforation at the inlet edge. The refrigerant from the second hollow chamber enters the channels located in the outlet edge, cools it and is discharged into the flow part.

The disadvantages of the known design of the turbine blades with a vortex cooling system are:

- inefficient cooling of the outlet edge of the blade due to the lack of turbulization of the cooling stream;

- the cooling curtain on the side surfaces of the blades is blown off by the oncoming flow, which leads to a decrease in cooling efficiency and an increase in the flow rate of the refrigerant due to its discharge into the flow part;

- due to the connection in the cooling cell of the channels with a twisting device, the twist intensity in the subsequent channels is reduced.

The technical result of the claimed invention is to increase the cooling efficiency, and therefore, increase the resource of the blade.

The specified technical result is achieved by the fact that in the body of the blade there is a central hollow chamber supplying additional refrigerant through swirling devices located along the height of the cooling cylindrical channels at a distance of 4 and 8 calibers, referred to the diameter of the cooling channels, and a vortex matrix is placed in the outlet edge . The blade contains the lower and upper receivers. Cooling cylindrical channels communicate with the lower and upper receivers.

Using a cyclone-vortex cooling scheme allows to achieve the required uniformity of temperature along the contour and along the height of the blade, providing a high degree of cooling, while maintaining the flow rate of the cooler used for this purpose.

The invention is illustrated by drawings.

Figure 1 presents a General view of the scapula.

Figure 2 shows a section of the pen of the input edge of the blade of figure 1, section AA.

Figure 3 shows a cross section of the feather of the blade of figure 1, section bb.

Figure 4 presents a cross section of the feather of the blade of figure 1, section CC.

Figure 5 shows a section of the feather of the blade of figure 4, section EE.

Figure 6 shows a General view of the side surface of the scapula.

In Fig.7 shows a section of the pen blade of Fig.6, section D-D

On Fig shows a section of the lower receiver of the blades of Fig.6, section F-F

The nozzle blade of a gas turbine with a cyclone-vortex cooling system (Fig. 1) contains a feather 1 with lower 2 and upper 3 fastening elements to its engine body. In the input edge 4, shown in FIG. 2, a longitudinal channel 5 is made, which communicates with the central hollow chamber 7 by twisting devices 8. The central hollow chamber 7 is connected to the lower receiver 6 located normally to it, as shown in FIG. The lower receiver 6 communicates with the supply channel of the refrigerant 9. Channel 5 of the input edge communicates with the upper receiver 10 for the removal of the cooler (figure 2). Along the entire height of the pen, the input edge contains a perforation 11 (FIG. 2) to create a cooling curtain. In the side walls along the entire height of the feather blade is made of cylindrical channels 12 with a diameter of 2 mm with air supply through a swirling device 13 (figure 2) from the lower receiver 6. The body of the blade contains a central hollow chamber 7 connected to the lower receiver 6 and cooling cylindrical channels 12 twisting devices 14 located at a height of 4 and 8 calibers (referred to the diameter of the cooling channels 12) from the root section of the scapula. The cooling cylindrical channels 12 communicate with the upper receiver 10, which connects the vortex matrix 15 with the release of the cooler through the slit of the output edge 16.

The nozzle blade of a gas turbine with a cyclone-vortex cooling system operates as follows. The compressed cooler flows through the coolant supply channel 9 and the lower receiver 6 and from the central hollow chamber 7 through the screw devices 8 into the channel 5. A part of the refrigerant from the channel 5 is discharged through the perforation 11 in the inlet edge 4 into the gas duct of the engine, creating a cooling curtain on the surface of the inlet 4, part of the cooler from channel 5 enters the upper receiver 10 and is discharged into the vortex matrix 15. From the lower receiver 6, compressed air through the swirling device 13 in the form of an intensively swirling flow enters the cooling cylindrical channels 12. An intensively swirling flow moves along the periphery of the channels 12, loses its swirl during the dissipative effect of viscous forces and loss of momentum on the generation of turbulence and coherent vortex structures, however, this does not happen due to the supply of a cooler from the central hollow chamber 7 through twisting devices 14 Thus, on the axis of the cylindrical channels there is no reverse axial flow in the form of a forced vortex.

The refrigerant from the cylindrical channels 12 enters the upper receiver 10, from which, passing through the vortex matrix 15, the cooling stream is turbulized and discharged through the slit of the output edge 16.

The swirling of the flow and its intense turbulization provide a significant increase in the heat transfer coefficient. The design of the cyclone-vortex convective-film cooling system of the nozzle blade of a gas turbine will ensure an increase in the temperature level in front of the gas turbine by 100-200 ° C and a uniform temperature distribution over the surface of the blade.

Claims (4)

1. The nozzle blade of a gas turbine with a cyclone-vortex cooling system containing twisting devices, cooling cylindrical channels, perforation of the inlet edge, characterized in that the body of the blade has a central hollow chamber, which additionally supplies refrigerant through the twisting devices located along the height of the cooling cylindrical channels at a distance equal to 4 and 8 calibers, referred to the diameter of the cooling channels, and a vortex matrix is placed in the outlet edge of the blade. 2. The nozzle blade of a gas turbine according to claim 1, characterized in that the blade contains lower and upper receivers. 3. The nozzle blade of a gas turbine according to claim 2, characterized in that the cooling cylindrical channels communicate with the lower and upper receivers. 4. The nozzle blade of a gas turbine according to claim 3, characterized in that the vortex matrix is connected to the upper receiver.

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