RU2642718C1 - Blisk of cooled fuel feed pylons - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: each pylon has three channels plugged from side, open ends of two of these channels are closed by plugs, channels are connected by holes, and in central channel there is a damper with several holes.

EFFECT: elimination of pylons burnout at high thermal loads, enhanced reliability of blisk of fuel supply, expanded performance range of fuel consumption at practically constant pressure drop on nozzles for improvement of combustion efficiency of fuel-air mixture.

2 cl, 4 dwg

Description

The invention relates to the field of aerospace engineering and can be used to supply fuel to a high-speed air stream in promising ramjet engines of intra-atmospheric aircraft.

From the existing level of technology, an aerodynamic flame stabilizer for afterburner combustion chambers of the WFD of the company MTU is known (German patent No. 2329346, F02K 3/10, 03/08/73). This stabilizer has an aerodynamic profile, on both surfaces of which there are nozzle openings through which the finished air-fuel mixture is supplied into the air stream under pressure, thereby ensuring a stable combustion process and minimal hydraulic flow loss in the chamber. To prepare the air-fuel mixture, the stabilizer has a mixing chamber with a nozzle device — a tube — and one or more air cavities. Air enters the air cavities, from where it enters the mixing chamber through openings located on its outer wall. Fuel is also injected into the chamber. A homogeneous air-fuel mixture from the chamber is injected into the external stream. The ignition of the fuel-air jets is carried out by a spark plug placed at the end of the recirculation zone.

The disadvantage of this type of stabilizer is the difficulty of protecting it from high values of heat fluxes acting on the stabilizer from high-speed air flow, due to which there is no protection of the most heat-stressed place - the front and rear edges of the stabilizer. In addition, it is not possible to compensate for the thermal deformation of the stabilizer design, which, with strong heating, can cause its destruction. The use of a spark plug to ignite the fuel mixture creates constructive additional complexity and unreliability in operation.

Closest to the claimed technical solution is the design described in the method of auto-ignition of the fuel mixture (RF patent No. RU 2444639, F02C 7/26, 03/10/2012), characterized in that the combustion chamber of the ramjet engine contains a rack for supplying fuel , which is made in the form of a body of an aerodynamic profile with leading and trailing edges, is fixed on one side inside on the wall of the combustion chamber through a support, is muffled on the other hand, and is oriented by the profile along the chamber path. In addition, the rack is equipped with one channel for supplying fuel and fuel nozzles in communication with the channel located on the leading edge. When a high-enthalpy high-speed air stream is supplied to the combustion chamber, local braking and an increase in the static temperature of the air flow occur at the front edge of the rack, and the supplied fuel mixes well against the air flow, heats up and ignites. Moreover, the design described in the method also differs in that a strut is used, which is further provided with a second fuel supply channel located at the rear of the strut and fuel nozzles communicating with the channel located along the trailing edge of the strut, the strut having a lateral cylindrical surface and is mounted on the wall of the combustion chamber through the support with the possibility of rotation along the path of the chamber, where the ignition of the fuel mixture is carried out by the fact that in the air flow rack in the place of fixing on the wall is set to the axis of the camera path obliquely at an angle of sweep, depending on the mode of operation of the engine. In addition, in the rack on the outer side surfaces, symmetrical longitudinal niches are performed, eddy combustion zones are formed in the niches and stabilization of the combustion of the oncoming flow of the fuel mixture is performed.

The disadvantages of this technical solution are the inadequacy for proper operation of the cooling rack of its front and rear edges at high temperatures of the incoming air flow, in the case of stabilization of the combustion of the fuel mixture near the rack and throwing flame against the air flow, as well as the strong dependence of the pressure drop on the nozzles, which are located in stand, from mass fuel consumption, which may adversely affect the combustion efficiency of the fuel-air mixture. In addition, the presence of a device for rotating the rack in the channel creates additional structural complexity and increases the likelihood of failure during operation.

The technical task of the invention is the creation of a blisk of cooled pylons for supplying fuel to a high enthalpy air flow inside a combustion chamber with a circular cross section, which would allow to obtain a significant technical result, namely, to exclude the possibility of burnout of pylons at high thermal loads, thereby improving the reliability of the blister of fuel supply, and also to expand the operating range for fuel consumption with a practically constant pressure drop across the nozzles to improve efficiency and burning the mixture of fuel and air.

This problem is solved in that the proposed blisk of cooled fuel supply pylons 2 (see Fig. 1), located between the input section 1 and the output section 5 of the combustion chamber, contains several fuel supply pylons 3. Each pylon 3 is made together with the blisk case 6 ( see Fig. 2), in which there is a distribution cavity 7. The distribution cavity is closed by a cylindrical cover 8 and connected to the pipe 4 (see Fig. 1). Each pylon has three channels muffled on one side of the channel 20, 11, 14 (see Fig. 2). The open ends of the channels 11 and 14 are closed by plugs 9 and 10, respectively. Channels 20 and 14 are connected by a hole 16, and channels 14 and 11 are connected by a hole 13. Plugs 12 and 15 are installed in holes 16 and 13, respectively. A shutter 19, an o-ring 18, a retaining ring 21 and a conical spring 17 are located in the central channel 11. Holes 24 are made in the shutter 19 (see Fig. 3). Two ledges 22 (one on each side) were made on the lateral surfaces of each pylon, each of which had several jet nozzles 23.

The technical essence of the invention is illustrated by drawings:

In FIG. 1 shows a general arrangement of a blisk of cooled fuel supply pylons, with FIG. 1 the following notation is accepted:

1 - input section of the combustion chamber;

2 - blisk of cooled fuel supply pylons;

3 - fuel supply pylons;

4 - pipe;

5 - output section of the combustion chamber.

In FIG. 2 is a longitudinal sectional view of the pylon, with FIG. 2 adopted the following notation:

6 - blisk body;

7 - distribution cavity;

8 - a cylindrical lid of the cavity;

9 - a stub;

10 - a stub;

11 - channel;

12 - a stub;

13 - hole;

14 - channel;

15 - a stub;

16 - hole;

17 - a conical spring;

18 - a sealing ring;

19 - shutter;

20 - channel;

21 - a lock ring.

In FIG. 3 shows a cross-sectional diagram of a pylon AA (position 1), with FIG. 3 adopted the following notation:

22 - ledges;

23 - jet nozzle;

24 - holes in the shutter.

In FIG. 4 shows a cross-sectional diagram of a pylon AA (position 2).

The device operates as follows: fuel enters through the nozzle 4 into the distribution cavity 7 and is distributed between the pylons. Further, the fuel sequentially passes through the channel 20, hole 16, channel 14, hole 13 and enters the cavity of the shutter 19. When passing through channel 20, hole 16 and channel 14, the fuel intensively cools the edges of the pylon and eliminates the possibility of burnout under high thermal loads, thereby increases the reliability of the fuel supply blisk. Under the pressure of the fuel, the shutter 19 lowers to a state of equilibrium of forces from the fuel pressure and the action of the conical spring 17. When the holes 24 located in the shutter and the jet nozzles 23 coincide, the jet nozzles 23 open and the fuel through them enters the outlet section of the combustion chamber 5. The equilibrium state determined by the number of open jet nozzles 23, the elasticity of the conical spring 17 and the mass flow of fuel. Depending on the mass flow rate of the fuel, the shutter 19 is shifted by different distances, thereby opening the necessary number of nozzles 23 (with an increase in the flow rate, more nozzles are open), which makes it possible to realize the automatic control mode and expand the operating range for fuel consumption with a practically constant pressure drop across the nozzles for Improving the efficiency of combustion of fuel with air. The upper position of the shutter 19 is limited by the locking ring 21. To prevent fuel from entering the area between the shutter 19 and the conical spring 17, a sealing ring 18 is installed in the hole 11. The step 22 and the supply of fuel at an angle to the axis of the combustion chamber improves mixture formation and increases the combustion efficiency of the fuel with air.

Conclusion: due to the new design solution in the proposed blister of fuel supply pylons, namely, the presence of special holes and channels, as well as the location in the central hole of each pylon of a damper, a conical spring, a retaining ring and an o-ring, the problems of eliminating the possibility of burnout of the pylons at high heat loads are solved thereby increasing the reliability of the fuel supply blisk, and expanding the operating range for fuel consumption with a practically constant pressure drop across the nozzles for better the efficiency of combustion of a mixture of fuel with air. In addition, the problem of improving mixture formation is additionally solved by supplying fuel at an angle to the axis of the combustion chamber and making steps on the side surfaces of the pylons.

The invention can be used in the field of aerospace engineering, when creating effective and reliable power plants, where the problems of organizing an effective combustion process and ensuring the efficiency of contraction are very relevant.

Information sources

1. The patent of Germany №2329346, F02K 3/10, 03/08/1973

2. RF patent No. RU 2444639, F02C 7/26, 03/10/2012

Claims (2)

1. The blister of the fuel supply pylons, comprising a housing with which several pylons with jet nozzles are made together and in which there is a distribution cavity closed by a cylindrical lid and connected to a nozzle, characterized in that each pylon has three channels muffled from one side, the open ends of two of these channels are closed with plugs, the channels are connected by holes, and in the central channel there is a damper with several holes, an o-ring, a snap ring and a conical spring. 2. The brightness of the fuel supply pylons according to claim 1, characterized in that on the side surfaces of each pylon two steps are made (one on each side), each of which has several jet nozzles.

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