RU2704055C1 - Fuel system of main combustion chamber of gas turbine engine - Google Patents

Abstract

FIELD: engine building.

SUBSTANCE: invention relates to aircraft engine building, particularly, to fuel supply system of main combustion chamber of gas turbine engine and fuel manifold for spraying of liquid fuel. Invention objective is to preserve prolonged burning at one or several duty nozzles at cutoffs of fuel supply to collector for further combustion recovery without use of ignition system. Set task is solved by the fact that in the collector design there is an open (one or more) centrifugal double-flow open-type nozzle with a protective cap, which at cutouts of fuel supply to collector switches to autonomous power supply with low fuel consumption, which ensures maintenance of optimum coefficient of excess air supplied to nozzle end through channels of anti-carbon cap. At that, combustion zone is arranged by swirling of this air directly behind nozzle end.

EFFECT: long-term maintenance of combustion in the zone of the duty nozzle, which ensures recovery of combustion in the main combustion chamber at sharp drops of fuel consumption, operation of the anti-missile system, start-up at autorotation modes, et cetera, without use of ignition system.

3 cl, 2 dwg

Description

The invention relates to the field of aircraft engine manufacturing, in particular, to a fuel supply system for a main combustion chamber of a gas turbine engine and a fuel manifold with nozzles for sawing liquid fuel.

The processes of mixture formation in the combustion chambers of gas turbine engines significantly affect the organization of combustion, the reliability and efficiency of the combustion chambers, and the thermal regime of individual engine elements.

A utility model No. 64324 is known for a combustion chamber of a gas turbine engine, including a housing, a fuel manifold, nozzles, swirls, diffusers and a heat pipe with an external and internal casing, on which there are coolants, while the heat pipe is divided into two combustion zones: standby and the main one, and the fuel manifold is a block of two collectors, one of which is connected to the nozzles of the standby zone, and the other to the nozzles of the main zone. The disadvantage of this model is the significant length of the flame tube, determined by the separation of the combustion zones and collectors with nozzles along the length of the combustion chamber. In this case, the minimum fuel consumption for combustion in the duty zone is significant, and a short-term cut-off of the fuel supply in it causes the flame to die out in the combustion chamber.

The closest prototype is the collector of the main combustion chamber with open-type centrifugal double-circuit nozzles with anti-burn caps, which are structurally capable of restoring combustion in the main combustion chamber due to fuel residues flowing from the lower nozzles in the manifold pipelines during short-term cutoffs of the fuel supply to the collectors when the anti-surge systems, stopcocks or relief and stop valves (see, for example, Kirpichev A.S., Kotsyubinsky S.V., Mosyagin V.V. V the restoration of combustion in the main combustion chamber with open nozzles // Klimov readings-2012: Promising directions for the development of aircraft engine manufacturing enterprises: a collection of reports of an international scientific and technical conference. - St. Petersburg: Publishing House of the Polytechnic University, 2012. - 132 ... 140 p.) . The disadvantage of the described collector is the limitation of the duration of holding the flame at the end of the nozzle with the volume of residual fuel, determined by the time of emptying of the pipelines and the fuel collector, as well as the possibility of extinction of this residual combustion during the evolution of the aircraft.

The objective of the invention is the preservation of long-term combustion on one or more duty nozzles with cut-offs of fuel supply to the low-flow manifold for subsequent recovery of combustion without using an ignition system.

The problem is solved in that an on-duty (one or more) open-type centrifugal double-circuit nozzle with an anti-burn cap is allocated in the fuel supply system, which, when cutting off the fuel supply to the low-flow manifold, switches to autonomous power supply with on-demand fuel consumption, ensuring the maintenance of an optimal coefficient of excess air, coming to the end of the nozzle through the channels of the anti-burn cap. In this case, the combustion zone is organized by the swirl of this air directly behind the end of the nozzle.

In order to restore the engine operating modes to all nozzles of the low-flow manifold, including the one on duty, fuel consumption is determined, determined by the engine control unit on the basis of pressure and air flow into the combustion chamber, and due to the transfer of flame from the combustion zone of the standby nozzle, combustion is restored in the entire volume of the combustion chamber .

As a duty nozzle, a starting nozzle may be used.

In the standby nozzle, self-contained low-flow power can be supplied through a central nozzle.

The technical result of the claimed invention is to ensure the restoration of combustion in the main combustion chamber after sharp discharges of fuel consumption, the operation of the anti-surge system, the failure of spark plugs, etc.

The fuel supply system of the main combustion chamber of a gas turbine engine, comprising a pump unit, a fuel tank, a fuel flow regulator, a distributor, a pressure sensor, a control unit, small and primary flow fuel manifolds and a nozzle, which also further comprises an on-duty fuel manifold including at least one double-circuit nozzle open type, consisting of a housing, threaded filters, spray nozzles of small and basic fuel consumption and an anti-burn cap, while the line The fuel supply to the nozzles of the standby manifold contains shut-off and non-return valves, and the fuel supply line of the low-flow manifold nozzles is connected to the fuel supply line of the stand-by nozzles through the check valve.

Fuel to the nozzles of low consumption of the nozzles of the standby fuel manifold is supplied at a rate proportional to the flow rate of air through the anti-burn cap.

As nozzles of the standby fuel manifold, starting nozzles are used.

The invention is illustrated by graphic materials on which are presented:

FIG. 1 Fuel supply system for on-duty combustion, where

1 - a gas turbine combustion chamber;

2 - fuel collector on-duty nozzles;

3 - a fuel collector of nozzles of low consumption;

4 - a fuel collector of nozzles of the main expense;

5 - nozzles;

6 - pump unit;

7 - a fuel tank;

8 - fuel consumption regulator;

9 - the distributor;

10 - pressure sensor;

11 - shut-off valve;

12 - non-return valves, a) in the line of the fuel manifold of the standby nozzles, b) in the line connecting the fuel collector of the standby nozzles with the fuel collector of the low-flow nozzles;

13 - control unit.

FIG. 2 Combustion pattern at the end of the on-duty dual-circuit fuel nozzle of the open type with the fuel consumption on duty, where

14 - nozzle body;

15 - threaded filter of small and standby fuel consumption;

16 - threaded filter for the main fuel consumption;

17 - swirl small and standby fuel consumption;

18 - swirl main fuel consumption;

19 - nozzle of the main fuel consumption;

20 - nozzle of small and duty fuel consumption;

21 - anti-burn cap;

22 - air channel;

23 - toroidal combustion zone;

24 - zone reverse currents.

The fuel supply system of the combustion chamber 1 includes a fuel manifold for stand-by nozzles 2, a fuel manifold for low-flow nozzles 3, a fuel manifold for main-flow nozzles 4, dual-circuit fuel nozzles 5, a pump unit 6 connected to the fuel tank 7. Exit from the pump unit 6 through the main fuel line through the fuel consumption regulator 8 is connected to the distributor 9. The regulator 8 and the distributor 9 supply and distribute fuel to the collectors 2, 3 and 4. The pressure sensor 10 of the combustion chamber 1 is connected with the regulator 8. 8. A shut-off valve 11 and a non-return valve 12-a) are installed in the line supplying fuel to the collector of the standby nozzles 2. The line of the fuel collector of the low-nozzle nozzles 3 is connected to the line of the fuel collector of the standby nozzles 2 through the check valve 12-b). Position 13 indicates the control unit.

Standby nozzles consist of a housing 14, a threaded filter for small and standby fuel consumption 15, a threaded filter for main fuel consumption 16, a swirl of small and standby fuel consumption 17, supplying fuel to the nozzle 20, a swirl of the main fuel consumption 18, supplying fuel to the nozzle 19, anti-burn a cap 21, forming an air channel 22, which creates a toroidal combustion zone 23 near the zone of reverse currents 24. The nozzles of the collectors 3 and 4 can be made single-circuit.

When the engine is running, air enters into the combustion chamber 1 and proportionally to its flow rate or pressure measured by the sensor 10, from the fuel tank 7 using the pump unit 6, through the flow regulator 8 and distributor 9, the fuel is fed and dispensed to the low-flow fuel manifold 3 and the fuel main flow collector 4. Part of the fuel dosed by regulator 8 for the low-flow fuel manifold 3 enters through the check valve 12-b) into the fuel manifold of the standby nozzles 2. In this case, in the main burner mode I control unit 13 closes the shutoff valve 11, fuel flow to the fuel injector duty manifold 2 and nozzle fuel injector function as small collector 3 flow.

When a command is issued from the control unit 13 to turn on the standby fuel supply mode, the fuel supply abruptly stops the fuel supply to the main flow manifold 4, the low-flow fuel manifold 3 and the nozzles of the collector of the on-line nozzles 2 through the non-return valve 12-b). Simultaneously with the pressure drop in the low-flow fuel manifold 3, the shut-off valve 11 opens and the fuel through the non-return valve 12-a), closing the non-return valve 12-b), enters the fuel manifold of the on-line injectors 2. Interruption of the fuel supply to the pipelines of the on-line injectors 2 is not allowed . The regulator 8 is proportional to the air pressure measured by the sensor 10 and, through the valve 11, delivers the required amount of fuel necessary for stable combustion in zone 23 to the fuel manifold of the on-duty nozzles 2, creating a condition for the optimal combustion of the air-fuel mixture, even when the air flow is reduced to near zero values during autorotation or before engine shutdown. The air passing through the channel 22 of the anti-burn cap 21 creates behind it a toroidal combustion zone 23 due to the formation of a reverse current zone 24. The kinetic energy of fuel atomization, as part of the velocity field behind the nozzle, disappears, which causes a decrease in the toroidal combustion zone 23 and the reverse zone currents 24, bringing them close to the end of the anti-burn cap 21.

When a command is sent from the control unit 13 to increase the operating mode, the fuel consumption increases to the low-flow fuel manifold 3. The non-return valve 12-b) opens with pressure and the fuel of the low-flow manifold 3 enters the fuel manifold of the standby nozzles 2. Due to the kinetic component of fuel atomization there is an increase in the combustion zone 23 and the zone of reverse currents 24 with the connection of an additional parietal layer of air from the front device of the flame tube to the combustion process. This leads to the spread of the flame from the standby nozzles 2 to the nozzles of the low-pressure fuel collector 3 of the combustion chamber and to an increase in the engine operating mode to the parameters set by the fuel consumption regulator 8 upon a command from the control unit 13. The shut-off valve 11 can be closed as if instructed by the control unit 13, and the fuel pressure passing the check valve 12-b) from the low-flow fuel manifold 3 and closing the check valve 12-a). A further increase in fuel consumption is produced by the regulator 8 through the distributor 9 in the fuel collector of the main flow 4.

Claims (3)

1. The fuel supply system of the main combustion chamber of a gas turbine engine, comprising a pump unit, a fuel tank, a fuel flow regulator, a distributor, a pressure sensor, a control unit, fuel collectors of small and main flow rates and nozzles, characterized in that it further comprises a standby fuel manifold including at least at least one open-type double-circuit nozzle, consisting of a housing, threaded filters, spray nozzles of small and main fuel consumption and an anti-burn cap, while the fuel supply line to the nozzles of the standby manifold contains shut-off and non-return valves, and the fuel supply line of the low-flow manifold nozzles is connected to the fuel supply line of the stand-by nozzles through the check valve. 2. The system according to p. 1, characterized in that the fuel to the low-flow nozzles of the nozzles of the standby fuel manifold is supplied with a flow proportional to the air flow through the anti-burn cap. 3. The system according to claim 1, characterized in that the starting nozzles are used as nozzles of the standby fuel manifold.

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