RU2674229C1 - Bypass gas turbine engine cooled turbine - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: bypass gas turbine engine cooled turbine contains distributing manifold with the high-temperature air source connection unit, manifold with the low-temperature air source connection unit, communicated with the high-temperature air source inter-disk cavity, the high and low pressure turbines impellers, the high and low pressure turbines rear supports with bearings; high and low pressure turbines oil cavities communicate to each other through the system of holes made in the low pressure turbine disk trunnion; the high and low pressure turbines pressurization cavities and pre-oil cavities. Low-pressure turbine pre-oil cavity is connected to the atmosphere by means of placed in the low-pressure turbine rear support air ducts, and the high-pressure turbine pre-oil cavity is connected to the low-temperature air source. High-pressure and low-pressure turbine pre-oil cavities communicate to each other and through the movable oil seals to the same-name oil cavities. Cooled turbine is equipped with placed in the high-pressure turbine pre-oil cavity dividing partition by the channels made in the high-pressure turbine rear support, outlets and the thermal screen. Thermal screen is made of two shells having the air gap between them, is installed in thee low-pressure turbine pre-oil cavity and with the high-pressure turbine rear support forms the additional air duct. Dividing partition divides the high-pressure turbine pre-oil cavity into two chambers, one of which is connected to the high-pressure turbine pressure chamber and through channels is to the low-pressure turbine pre-oil cavity, and another chamber through an additional air duct and outlets is communicated to the low-pressure turbine pre-oil cavity.

EFFECT: invention is aimed at increase in the engine efficiency and reliability.

1 cl, 3 dwg

Description

The invention relates to the field of operation of gas turbine engines, in particular to engines used as a drive for gas pumping units and power plants and can be used in the development of power plants with oil cooling in a closed circulation system and the modernization of heating systems to maintain the working temperature of oil in oil tanks of gas turbine engines.

Known cooled turbine of a double-circuit gas turbine engine containing a distributing manifold with a node for connecting to a source of high-temperature air, a collector with a node for connecting to a source of low-temperature air, an inter-disk cavity in communication with a source of high-temperature air, the impellers of high and low pressure turbines with rotor blades and disks , axles of discs of high and low pressure turbines, nozzle vanes, rear supports of high and low pressure turbines with bearings kami, oil cavities of high and low pressure turbines communicated with each other through a system of holes made in the journal of the disk of the low pressure turbine, pressurization cavity and pre-oil cavity of the high and low pressure turbine, and the pre-oil cavity of the low pressure turbine through air ducts located in the rear support of the turbine low pressure, in communication with the atmosphere, and the pre-oil cavity of the high-pressure turbine is in communication with a source of low-temperature air, while the pre-oil cavities of the high-pressure turbine and low pressure are communicated with each other and through oil movable seals with the same oil cavities.

(RF patent No. 26819, U1 IPC F02C 7/06, publ. December 20, 2002).

The disadvantage of this solution is that the "hot" air from a source of high-temperature air with a temperature of 400-450 ° C from the interdisc cavity is sent to the boost cavity, then to the pre-oil cavities of the back support of the high pressure turbine and the back support of the low pressure turbine and through oil movable seals enters the oil cavity, where the passing air heats up not only the oil, but also the structural elements of the oil support, from which the oil is heated additionally. Increased heating of the oil can lead to both an increase in the temperature of the bearing housing, which reduces its durability, and promotes coke formation on the support elements, which, on the one hand, can lead to a change in the properties of the oil, making it unusable, and, on the other hand, can lead to to the ignition of coke and oil on the support elements. As a result, there is a need for frequent oil changes, and in the event of a coke fire and a decrease in bearing life, the reliability and life of the turbine are reduced.

The objective of the invention is to increase the efficiency and reliability of the engine.

The technical result is the preservation of the properties of the used oil, increasing the reliability of the bearing and its durability, as well as eliminating the appearance of coke and the ignition of oil and coke during operation.

The technical result is achieved by the fact that a cooled turbine of a double-circuit gas turbine engine, comprising a distributing manifold with a unit for connecting to a source of high-temperature air, a collector with a unit for connecting to a source of low-temperature air, an inter-disk cavity in communication with a source of high-temperature air, and impellers of high and low pressure turbines with rotor blades and discs, trunnions of discs of high and low pressure turbines, nozzle vanes, rear turbine supports and low pressure with bearings, oil cavities of high and low pressure turbines communicated with each other through a system of holes made in the journal of the disk of the low pressure turbine, pressurization cavities and pre-oil cavities of the high and low pressure turbines, the pre-oil cavity of the low pressure turbine via air ducts, placed in the rear support of the low-pressure turbine is in communication with the atmosphere, and the pre-oil cavity of the high-pressure turbine is in communication with the source of low-temperature air, while asl cavities of the high and low pressure turbines are communicated with each other and through oil movable seals with the same oil cavities, on offer, it is equipped with a dividing wall located in the pre-oil cavity of the high pressure turbine, channels made in the rear support of the high pressure turbine, outlet openings and thermal screen made of two shells having an air gap between each other and connected to each other by fasteners installed in the pre-oil cavity of the turbines low pressure and forming an additional duct with the rear support of the high pressure turbine, while the dividing wall divides the pre-oil cavity of the high-pressure turbine into two chambers, one of which is connected with the pressurization cavity of the high-pressure turbine and through channels with the pre-oil cavity of the low-pressure turbine, and the other the chamber through an additional duct and exhaust openings is in communication with the pre-oil cavity of the low pressure turbine.

The presence of a dividing wall, located in the pre-oil cavity of the high pressure turbine and dividing it into two chambers, allows you to separate the flows of "cold" and "hot" air.

The presence of channels made in the rear support of the high-pressure turbine and their communication from one of the chambers in the pre-oil cavity of the high-pressure turbine and with the pre-oil cavity of the low-pressure turbine allows directing "hot" air coming from the pressurization cavity of the high-pressure turbine to the pre-oil cavity of the turbine low pressure, thus isolating the pre-oil cavity of the high-pressure turbine from the influx of "hot" air, and increasing the percentage of influx of "cold" air from the source of low temperatures air.

The presence of a thermo-screen and its placement in the pre-oil cavity of the low-pressure turbine, as well as the formation of an additional air duct between the elements of the rear support of the high-pressure turbine and the thermal screen, allows you to isolate “cold” air into the pre-oil cavity of the low-pressure turbine, thereby ensuring “washing” with “cold” the air of the structural elements of the rear support of the high-pressure turbine, the journal of the low-pressure turbine, as well as the elements of the oil cavities, which significantly reduces their temperature. It should be noted that in this case, “cold” air also enters the oil cavities of the high and low pressure turbines through oil-contact seals, ensuring the optimum level of oil temperature.

The implementation of the thermo-screen in the form of two shells having an air gap between each other and connected to each other by fasteners allows, on the one hand, to use a more robust structure by connecting the two shells to each other, and on the other hand, due to the presence of air inside the shells thermal resistance of the thermoscreen and ensures its effectiveness along its entire length.

The presence of the outlet openings ensures the blowing of "cold" air passing through the additional air duct into the pre-oil cavity of the low pressure turbine, while the area of the outlet openings can be used to control the percentage of the flow of "cold" air coming from the source of low-temperature air.

In FIG. 1 shows a longitudinal section through a cooled turbine.

In FIG. 2 shows location A of FIG. one.

In FIG. 3 shows location B in FIG. 2.

The cooled turbine of a double-circuit gas turbine engine contains a distributing manifold 1 with a unit for connecting to a source of high-temperature air 2, a collector 3 with a unit for connecting to a source of low-temperature air 4, an interdisc cavity 5 in communication with a source of high-temperature air 2, an impeller 6 of a high-pressure turbine 7 s the disk 8 and the blades 9, the impeller 10 of the low pressure turbine 11 with the disk 12 and the blades 13. The turbine also contains the pins 14 and 15 of the disks 8 and 12, respectively, blades and nozzle apparatus 16 and the back supports of high 17 and low pressure turbines 18 with bearings 19 and 20.

The turbine contains an oil cavity 21 of the high-pressure turbine 7 and an oil cavity 22 of the low-pressure turbine 11, interconnected through a system of holes 23 made in the journal 15 of the disk 12 of the low-pressure turbine 11, boost cavities 24 and 25, and pre-oil cavities 26 and 27 of the high turbine pressure 7 and low pressure turbine 11, respectively.

In this case, the pre-oil cavity 27 of the low-pressure turbine 11 is connected with the atmosphere through the air ducts 28 located in the rear support of the low-pressure turbine 18, and the pre-oil cavity 26 of the high-pressure turbine 7 is in communication with the source of low-temperature air 4. The pre-oil cavities 26 and 27 of the high-turbine 7 and low pressure 11 communicated with each other and through oil movable seals 29, 30 and 31 communicated with the same oil cavities 21 and 22.

The turbine contains a dividing wall 32 located in the pre-oil cavity 26 of the high-pressure turbine 7, channels 33 made in the rear support of the high-pressure turbine 17 and a thermal screen 34 consisting of two shells 35 and 36 connected to each other by fasteners 37. The turbine also contains an additional duct 38 formed by the rear support of the high pressure turbine 17 and the thermal screen 34.

The partition wall 32 divides the pre-oil cavity 26 of the high-pressure turbine 7 into two chambers 39 and 40. The chamber 39 is in communication with the pressurization cavity 24 of the high-pressure turbine 7 and through the channels 33 with the pre-oil cavity 27 of the low-pressure turbine 11. The chamber 40 through the additional duct 38 and the outlet openings 41 are in communication with the pre-oil cavity 27 of the low pressure turbine 11.

The turbine operates as follows.

To cool the turbine and pressurize the turbine bearings, the air from the source of high-temperature air 2 through the distributing manifold 1 and the blades of the nozzle apparatus 16 enters the interdisc cavity 5 and further into the boost cavity 24 and 25, and from them into the pre-oil cavities 26 and 27 of the high 7 and low turbines 11 pressure respectively.

At the same time, colder air from the source of low-temperature air 4 through the collector 3 enters the pre-oil cavity 26 of the high pressure turbine 7.

The dividing wall 32, located in the pre-oil cavity 26 of the high-pressure turbine 7, divides the air into a stream of "hot" air coming from the pressurization cavity 24 of the high-pressure turbine 7 into the chamber 39, where later through channels 33 made in the rear support of the high-pressure turbine 17, enters the pre-oil cavity 27 of the low-pressure turbine 11, and the stream of “cold” air entering the chamber 40, which enters the oil cavity 21 through the oil movable seal 29 and into the additional duct 38 formed th rear support the high pressure turbine 17 and Thermoscreens 34.

Passing through an additional duct 38, “cold” air washes the structural elements of the rear support of the high-pressure turbine 17, axle 15 of the low-pressure turbine 11, as well as the elements of the oil cavities 21 and 22, reduces heat transfer from the structural elements to the oil, thereby lowering the temperature level oils in oil cavities 21 and 22.

Further, the “cold” air through the outlet openings 41 enters the pre-oil cavity 27 of the low pressure turbine 11, where one part through the oil movable seal 30 enters the oil cavity 21 of the high pressure turbine 7, and the other part is mixed with the “hot” air entering from the pressurization cavity 25 of the low-pressure turbine 11 and from the chamber 39 of the pre-oil cavity 26 of the high-pressure turbine 7. A significant part of the air entering the pre-oil cavity 27 of the low-pressure turbine 11 through air ducts 28 located in the rear th support of the low pressure turbine 18, is released into the atmosphere, and a small amount of it enters the oil cavity 22 of the low pressure turbine 11 through the oil movable seal 31.

Since the oil cavities 21 and 22 of the high-pressure and low-pressure turbines 11 are interconnected by a system of openings 23, an average level of oil temperature is set in the oil cavities 21 and 22, which is largely influenced by the “cold” air from the source of low-temperature air 4, since its amount prevails.

The thermal screen 34, made in the form of two shells 35 and 36, having an air gap between each other and connected to each other by fasteners 37, is a heat-insulating element that not only separates the flows of “cold” and “hot” air, but also ensures the passage of “cold” »Air through an additional duct 38 without significant heating.

The calculations showed a 1.5-fold decrease in the heating of oil in the structure with the placement of a dividing wall and a thermo-screen compared to the original structure, which makes it possible to operate the product at high ambient temperature, the so-called "tropical" version.

The implementation of this invention by reducing the temperature of the oil ensures the stability of its properties and further reuse in the oil supply line to the bearings of the support, improving the working conditions of the bearings of the high and low pressure turbines and, as a result, increasing their service life and durability, as well as eliminating the formation of coke by turbine support structural elements.

Claims (1)

Cooled turbine of a double-circuit gas turbine engine, comprising a distributing manifold with a unit for connecting to a source of high-temperature air, a collector with a unit for connecting to a source of low-temperature air, an inter-disk cavity in communication with a source of high-temperature air, impellers of high and low pressure turbines with rotor blades and disks, axles of high and low pressure turbine disks, nozzle vanes, rear supports of high and low pressure turbines with bearings, mas the cavity of the high and low pressure turbines communicated with each other through a system of holes made in the journal of the disk of the low pressure turbine, pressurization cavity and pre-oil cavity of the high and low pressure turbine, the pre-oil cavity of the low pressure turbine by means of air ducts located in the rear support of the low pressure turbine is in communication with the atmosphere, and the pre-oil cavity of the high-pressure turbine is in communication with the source of low-temperature air, while the pre-oil cavities of the high and low turbines pressures are communicated with each other and through oil movable seals with the same oil cavities, characterized in that it is equipped with a dividing wall located in the pre-oil cavity of the high-pressure turbine, channels made in the rear support of the high-pressure turbine, exhaust holes and a thermal screen made of two shells having an air gap between each other and connected to each other by fasteners installed in the pre-oil cavity of the low pressure turbine and forming with the rear an additional duct is supported by a high-pressure turbine support, while the dividing wall divides the pre-oil cavity of the high-pressure turbine into two chambers, one of which is connected with the pressurization cavity of the high-pressure turbine, and through the channels with the pre-oil cavity of the low-pressure turbine, and the other chamber through the additional air duct and the outlets are in communication with a pre-oil cavity of the low pressure turbine.

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