RU2821680C1 - Gas turbine engine annular combustion chamber diffuser - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to devices for reduction of speed, formation of air flow ahead of front device of combustion chamber of gas turbine engine. Gas turbine engine annular combustion chamber diffuser comprises external and internal power housings, the diffuser external wall is connected to the external power housing by means of a flange connection and is fixed with close-fitting bolts, diffuser inner wall is connected to the inner power housing by means of a flange connection and is fixed with close-fitting bolts, flange joint connector is located in the plane of the front device; a union and a flange are placed on the outer wall.

EFFECT: invention allows to provide uninterrupted air flow, performance of finishing works on changing the profile of the outer and inner walls of the housings without making new housings, compressor coupling with combustion chamber housings in case of change in compressor design (reduction of height of blades of the last stage from guide vanes) without fabrication of new housings, stabilization of flow at speed boost at combustion chamber inlet.

4 cl, 4 dwg

Description

The invention relates to devices for reducing speed and forming an air flow in front of the front device of the combustion chamber of a gas turbine engine.

From the utility model RU 213844, a diffuser for the combustion chamber of a gas turbine engine is known, which contains a pre-diffuser, for which several sections of profiled surfaces are used.

The disadvantages of this useful model include:

Does not allow air bleed for engine needs,

Does not allow measurements of parameters in the combustion chamber diffuser.

From the invention patent RU 1032866, a gas turbine engine combustion chamber diffuser is known containing outer and inner shells and streamlined radial struts located between them.

The disadvantage of the invention is the presence of struts, which increase the resistance of the diffuser and increase pressure loss.

Also, this design does not allow finishing work to change the profile of the outer and inner walls of the housings without manufacturing new housings.

From the invention patent RU 26840, a gas turbine engine combustion chamber diffuser is known, containing outer and inner annular power housings connected to each other by radial power cast struts.

The disadvantage of the invention is the presence of struts, which increase the resistance of the diffuser and increase pressure loss.

Also, this design does not allow joining the compressor with the combustion chamber housings in the event of a change in the compressor design (reducing the height of the last stage blades from the guide vane) without manufacturing new housings

Does not provide flow stabilization when increasing the speed at the entrance to the combustion chamber

Does not allow the boundary layer to be destroyed by taking air from the wall surface.

From the invention patent RU 2365821, a diffuser is known for an annular combustion chamber with one zone, in particular for an aircraft turboprop engine, containing a separating element that separates the air flow leaving the compressor into two annular diffusion streams, while the separating element is formed by a thin sheet connected structural arms with inner and outer circularly symmetrical diffuser walls

In this invention, the expansion angle of each diffusion flow formed by the specified thin sheet in the diffuser is approximately 12-13, which is a necessary measure to ensure continuous flow in the diffuser and introduces additional resistance and pressure loss.

Also, this design does not allow finishing work to change the profile of the outer and inner walls of the housings without manufacturing new housings.

Does not allow measurements of parameters in the combustion chamber diffuser, since the parameters in one diffusion flow will differ from the parameters in another diffusion flow.

From the researched level of technology, a technical solution was identified that coincides with the declared technical solution in terms of the set of features and the achieved technical result according to the RF patent for invention No. 2696519; the essence is that the annular combustion chamber of a gas turbine engine contains a diffuser containing outer and inner annular power housings.

The disadvantages of the known invention are:

Does not provide continuous flow

Does not allow measurements of parameters in the combustion chamber diffuser.

It does not allow finishing work to change the profile of the outer and inner walls of the housings without manufacturing new housings.

It does not allow joining the compressor with the combustion chamber housings in the event of a change in the compressor design (reducing the height of the last stage blades from the guide vane) without manufacturing new housings.

Does not provide flow stabilization when increasing the speed at the entrance to the combustion chamber.

Does not allow the boundary layer to be destroyed by air movement.

It does not allow finishing work to change the profile of the outer and inner walls of the housings without manufacturing new housings.

Does not allow air sampling for engine needs.

The objective of the claimed invention is to eliminate the disadvantages of the prototype, namely:

Ensure continuous air flow.

Provide measurement of parameters in the combustion chamber diffuser.

Ensure that finishing work is carried out to change the profile of the outer and inner walls of the housings without manufacturing new housings.

Ensure the connection of the compressor with the combustion chamber housings in the event of a change in the compressor design (reducing the height of the last stage blades from the guide vane) without manufacturing new housings.

Ensure flow stabilization when increasing the speed at the entrance to the combustion chamber.

Ensure the destruction of the boundary layer during air movement.

Ensure that finishing work is carried out to change the profile of the outer and inner walls of the housings without manufacturing new housings.

Ensure air bleed for the engine needs.

The essence of the claimed technical solution is the diffuser of the annular combustion chamber of a gas turbine engine, containing external and internal power housings.

The proposed diffuser of the annular combustion chamber of a gas turbine engine is characterized by some design features:

The outer wall of the diffuser is joined to the outer power housing using a flange connection and secured with tight-fitting bolts, the inner wall of the diffuser is joined to the inner power housing using a flange connection and secured with tight-fitting bolts, the flange connection connector is located in the plane of the front device, a fitting and a flange are placed on the outer wall .

The diffuser has outer and inner walls with a smooth profile and an angle increasing from the inlet to the outlet section. The profiling of the walls of the annular diffuser is carried out according to the law of constancy of the pressure increase gradient along its length

The diffuser has an angle between the outer and inner walls of no more than 12°, increasing from the inlet to the outlet section, at the outlet of the outer and inner walls there is an internal pocket, the outlet part of the diffuser is located opposite the front device of the flame tube.

The diffuser has an outer wall with a smooth profile and a step, an inner wall with a smooth profile and an angle increasing from the inlet to the outlet section, on the outer wall there are holes in three equally spaced rows around the circumference and an external manifold for air intake is installed.

The goal is generally achieved by:

To ensure continuous air flow, the diffuser has outer and inner walls with a smooth profile and an angle that increases from the inlet to the outlet section. The profiling of the walls of the annular diffuser is carried out according to the law of constancy of the pressure increase gradient along its length To ensure the measurement of parameters in the combustion chamber diffuser, a fitting and a flange are placed on the outer wall, which makes it possible to measure the static pressure on the wall and install a pneumatic thermal comb to determine the oncoming flow pressure and its temperature.

To ensure finishing work on changing the profile of the outer and inner walls of the housings without manufacturing new housings, the outer wall of the diffuser is joined to the outer power housing using a flange connection and secured with tight-fitting bolts, the inner wall of the diffuser is joined to the inner power housing using a flange connection and fastened with tight-fitting bolts , the flange connection connector is located in the plane of the front device, which also provides access to the nozzles of the front device.

To ensure the joining of the compressor with the combustion chamber housings in the event of a change in the compressor design (reducing the height of the blades of the last stage from the guide vane) without manufacturing new housings, the outer wall of the diffuser is joined to the outer power housing using a flange connection and secured with tight-fitting bolts, the inner wall of the diffuser is joined to the inner power housing using a flange connection and secured with tight-fitting bolts.

To ensure flow stabilization when speed is accelerated at the entrance to the combustion chamber, the diffuser has an angle between the outer and inner walls of no more than 12°, increasing from the inlet to the outlet section, there is an internal pocket at the exit from the outer and inner walls, the outlet part of the diffuser is located opposite the front device flame tube.

To ensure the destruction of the boundary layer when air moves, the diffuser has three equally spaced rows of holes around the circumference and an external collector on the outer wall.

To ensure air intake for the engine needs, a diffuser

has an outer wall with a smooth profile and a step, an inner wall with a smooth profile and an angle increasing from the inlet to the outlet section, holes are placed on the outer wall in three equally spaced rows around the circumference and an outer manifold is installed.

An analysis of known technical solutions, carried out according to scientific, technical and patent documentation, showed that the set of essential features of the proposed technical solution is not known from the level of technology examined by the applicant, therefore, it meets the conditions of patentability of “novelty” and “inventive step”.

The claimed technical solution is illustrated by the drawing: FIG. 1, fig. 2, fig. 3 shows a longitudinal section of the diffuser of the annular combustion chamber of a gas turbine engine and options; fig. 4, (view of the fitting and flange).

The diffuser of the annular combustion chamber of a gas turbine engine contains an outer 1 and an inner 2 power housing. The claimed diffuser of the combustion chamber of a gas turbine engine is characterized by the presence of significant design changes compared to known analogues, providing the design with the ability to achieve its goals, namely, the outer wall 3 of the diffuser is joined to the outer power housing 1 using a flange connection 4 and is secured with tight-fitting bolts 5, the inner wall 6 of the diffuser is connected to the internal power housing 2 using a flange connection 7 and secured with tight-fitting bolts 8, the connector of the flange connection is located in the plane of the front device 9, on the outer wall 3 there is a fitting 10 and a flange 15, in which a pneumatic-thermal comb is installed (Fig. 4).

The diffuser (Fig. 1) has an outer 3 and an inner 6 wall with a smooth profile and an angle increasing from the inlet to the outlet section. The profiling of the walls 3, 6 of the annular diffuser is carried out according to the law of constancy of the pressure increase gradient along its length The diffuser (Fig. 3) has an angle between the outer 3 and inner 6 walls of no more than 12°, increasing from the inlet to the outlet section; at the exit from the outer 3 and inner 6 walls there is an internal pocket 11, the outlet part of the diffuser is located opposite the front fire device 9 pipes.

The diffuser (Fig. 2) has an outer wall 3 with a smooth profile and a step 12, an inner wall 6 with a smooth profile and an angle increasing from the inlet to the outlet section, on the outer wall 3 in three equally spaced rows around the circumference there are holes 13 and an outer collector 14 is installed. .

Based on the above, it seems possible to draw conclusions about the achievement of the stated goals, namely:

Continuous air flow is ensured by the fact that the diffuser has outer and inner walls with a smooth profile and an angle increasing from the inlet to the outlet section. The profiling of the walls of the annular diffuser is carried out according to the law of constancy of the pressure increase gradient along its length

Measurement of parameters in the combustion chamber diffuser is ensured by the fact that a fitting and a flange are placed on the outer wall.

It is ensured that finishing work on changing the profile of the outer and inner walls of the housings without manufacturing new housings is ensured by the fact that the outer wall of the diffuser is joined to the outer power housing using a flange connection and secured with tight bolts, the inner wall of the diffuser is joined to the internal power housing using a flange connection and secured with tight-fitting bolts, the flange connection connector is located in the plane of the front device.

The joining of the compressor with the combustion chamber housings is ensured in the event of a change in the compressor design (reducing the height of the blades of the last stage from the guide vane) without the manufacture of new housings in that the outer wall of the diffuser is joined to the outer power housing using a flange connection and secured with tight-fitting bolts, the inner wall of the diffuser is joined with the internal power housing using a flange connection and secured with tight-fitting bolts.

Stabilization of the flow is ensured when speeding up the speed at the entrance to the combustion chamber by the fact that the diffuser has an angle between the outer and inner walls of no more than 12°, increasing from the inlet to the outlet section, at the exit from the outer and inner walls there is an internal pocket, the outlet part of the diffuser is located opposite front device of the flame tube.

The destruction of the boundary layer during air movement is ensured by the fact that the diffuser has three equally spaced rows around the circumference of the hole and an external collector on the outer wall.

The intake of air for the needs of the engine is ensured by the fact that the diffuser

has an outer wall with a smooth profile and a step, an inner wall with a smooth profile and an angle increasing from the inlet to the outlet section, holes are placed on the outer wall in three equally spaced rows around the circumference and an outer manifold is installed.

Thus, in comparison with the prototype, the claimed technical solution provides generally more effective use for its intended purpose, that is, the claimed technical solution provides, by making changes to the design diffuser of the annular combustion chamber of a gas turbine engine, their more efficient use in the combustion chambers of gas turbine engines, namely:

Continuous flow of air is ensured, measurements of parameters in the combustion chamber diffuser are ensured, finishing work is ensured to change the profile of the outer and inner walls of the housings without manufacturing new housings, docking of the compressor with the combustion chamber housings is ensured in the event of a change in the compressor design (reducing the height of the last stage blades from the guide apparatus) without manufacturing new housings, stabilization of the flow is ensured when the speed at the entrance to the combustion chamber is accelerated, and destruction of the boundary layer during air movement is ensured. air bleed for engine needs is ensured

The air flow (Fig. 1., Fig. 2., Fig. 3) moves between the outer 1 and inner 2 power buildings, passing between the outer 3 and inner 6 walls. In this case, the outer wall 3 of the diffuser is joined to the outer power body 1 using a flange connection 4 and secured with fitting bolts 5, the inner wall 6 of the diffuser is joined to the inner power body 2 using a flange connection 7 and secured with fitting bolts 8. The flange connection connector is in the plane front device 9, which provides access to the nozzles of the front device 9 when disconnecting the outer wall 3 from the outer power housing 1 and disconnecting the inner wall 6 from the inner power housing 2.

The air flow (Fig. 1) passes between the outer 3 and inner 6 walls with a smooth profile made according to the law of a constant pressure gradient along its length and an angle increasing from the inlet to the outlet section, then without the occurrence of separations it enters the front device 9.

The air flow (Fig. 3) passes between the outer 3 and inner 6 walls having an angle of no more than 12°, increasing from the inlet to the outlet section, moving towards the exit from the outer 3 and inner 6 walls, part of the air enters the inner pocket 11 in which a vortex is formed stabilizing in this area. Air from the outlet part of the diffuser enters the front device 9 of the flame tube without turning the flow, since it is located opposite.

The air flow (Fig. 2) passes between the outer wall 3 with a smooth profile and step 12 and the inner wall 6 with a smooth profile and an angle increasing from the inlet to the outlet section. When air flows near the walls, a boundary layer is formed to destroy it; on the outer wall 3, holes 13 are placed in three equally spaced rows around the circumference and an external collector 14 is installed, which allows air to be taken from the wall surface and eliminate the air flow from the boundary layer. The extracted air can be used for the needs of the engine.

The flow parameters in the diffuser are measured (Fig. 4), for which a fitting 10 and a flange 15 are placed on the outer wall 3, which makes it possible to measure the static pressure on the wall and install a pneumatic thermal comb to determine the pressure of the oncoming flow and its temperature.

If the design of the compressor is changed, for example, reducing the height of the blades of the last stage and the guide vane leads to the need to manufacture new combustion chamber housings to ensure their connection with the compressor. In this case, rearrangement into any version of the diffuser is possible (Fig. 1, Fig. 2, Fig. 3). This is ensured by the fact that the outer wall 3 of the diffuser is joined to the outer power body 1 using a flange connection 4 and secured with tight-fitting bolts 5, the inner wall 6 of the diffuser is joined to the inner power body 2 using a flange connection 7 and secured with tight-fitting bolts 8. That is, it seems the possibility of rearranging the outer wall 3 of the diffuser 3 and the inner wall 6 of the diffuser from any of the proposed options.

Claims (4)

1. Diffuser of the annular combustion chamber of a gas turbine engine, containing outer and inner power housings, characterized in that the outer wall of the diffuser is joined to the outer power body by means of a flange connection and secured with tight-fitting bolts, the inner wall of the diffuser is joined to the inner power body by means of a flange connection and it is fastened with tight-fitting bolts, the flange connection connector is located in the plane of the front device, a fitting and a flange are located on the outer wall. 2. The diffuser according to claim 1, characterized in that it has outer and inner walls with a smooth profile and an angle increasing from the inlet to the outlet section, the profiling of the walls of the annular diffuser is carried out according to the law of constancy of the pressure increase gradient along its length 3. The diffuser according to claim 1, characterized in that it has an angle between the outer and inner walls of no more than 12°, increasing from the inlet to the outlet section, at the outlet of the outer and inner walls there is an internal pocket, the outlet part of the diffuser is located opposite the front fire device pipes. 4. The diffuser according to claim 1, characterized in that it has an outer wall with a smooth profile and a step, an inner wall with a smooth profile and an angle increasing from the inlet to the outlet section, holes are placed on the outer wall in three equally spaced rows around the circumference and an outer collector.