RU2438031C2 - Control method of fuel flow to afterburner of gas turbine engine - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: control method of fuel flow to afterburner of gas turbine engine consists in the fact that according to measured air temperature at the engine inlet, air pressure after compressor, gas pressure after engine turbine, position of throttle lever and fuel flow to the main combustion chamber (MCC) there controlled is fuel flow to afterburner. In addition, during augmented acceleration, at connection of successive fuel manifold of afterburner, afterburner fuel consumption is increased during its filling through the "previous" manifold by the value of the volume of the successive one. Smooth change of effective fuel consumption and therefore smooth change of engine thrust during acceleration is provided; i.e. ACS operating quality is improved.

EFFECT: higher operating reliability of the engine.

1 dwg

Description

The invention relates to the field of aircraft engine manufacturing and can be used in electronic hydromechanical systems (ACS) for automatic control of gas turbine engines (TRDF) with afterburner combustion chamber (FCC).

A known method of controlling fuel consumption in the FCC turbofan engine, which consists in the fact that the measured air pressure behind the engine compressor controls the fuel consumption in the FCC (afterburner fuel) (Cherkasov BA "Automation and regulation of the WFD", M., "Engineering", 1965).

The disadvantage of this method is that it does not ensure that the operating mode of the gas generator is unchanged, because the effect of boost fuel supply on the pressure drop across the turbine is not controlled. This can lead to a significant deviation of the gas temperature in front of the turbine from the calculated value. This, in turn, reduces the reliability of the engine and leads to accelerated development of its resource.

Closest to this invention in technical essence is a method of controlling fuel consumption in the FCC turbofan engine, which consists in the fact that the measured air temperature at the engine inlet, air pressure behind the engine compressor, gas pressure behind the engine turbine, position of the engine control lever (ORE) and the fuel consumption in the main combustion chamber (ACS) (main fuel consumption) is controlled by the fuel consumption in the FCC (Shlyakhtenko S. M. “Theory of aviation WFD”, M., “Engineering”, 1974).

The disadvantage of this method is that it does not take into account the significant effect of the design of the fuel system of the afterburner circuit of the engine on the dynamics of the FCC, namely, it does not take into account the effect of the process of filling the fuel collectors on the process of changing the engine thrust during afterburner injectivity. This leads to a stepwise change in the effective fuel consumption and, accordingly, to a stepwise change in the engine thrust during the throttle response. For modern Al-31F and D30-F6 engines, which have five groups of collectors in the FCC and strict requirements for the time the engine takes to the “full boost” mode (1 ... 2 s) without draft failures, this drawback is significant. A stepwise change in the effective fuel consumption can lead to an undersupply of engine thrust at the right time. This reduces the reliability of the engine and the safety of the aircraft.

The aim of the invention is to increase the reliability of the engine and the safety of the aircraft by improving the quality of the ACS in afterburning modes of the engine.

The goal is achieved by the fact that in the method of controlling fuel consumption in the FCC turbofan engine, which consists in the fact that the flow rate is controlled by the measured air temperature at the engine inlet, air pressure behind the compressor, gas pressure behind the engine turbine, throttle position and fuel consumption fuel in the FCC, in addition, in the process of afterburning pickup, when connecting the next FKS fuel collector for the time of its filling, the afterburner fuel consumption through the “previous” collector is increased by the size of the queue th.

The figure shows a diagram of a device that implements the inventive method.

The device contains a series-connected block 1 of engine and air parameters sensors at the engine inlet, an electronic controller 2 (ER) of the engine operating modes, a block of electrohydroconverters 3, afterburner fuel dispensers 4 are connected to the output of block 3 (one for each FCS fuel collector), each the dispenser 4 through its shut-off valve (ZK) 5 is connected to its fuel collector FKS, the input of each ZK 5 is connected to the ER 2.

The device operates as follows.

According to the measured at the engine inlet air temperature using DB 1, the air pressure behind the engine compressor, the gas pressure behind the engine turbine, the throttle position and fuel consumption in the ACS ER 2 forms the set value of the fuel consumption in the FCC

where GT f ass - a given fuel consumption in the FCC,

α ores - angle of ore installation

TVh - air temperature at the engine inlet,

Pk - air pressure behind the engine compressor,

RT is the gas pressure behind the engine turbine,

GT ox - measured fuel consumption in the ACS.

Examples of dependence (1) are given in the book Shlyakhtenko S.M. "The theory of aviation WFD", M., "Engineering", 1974

Depending on the value of the predetermined afterburner fuel consumption, ER 2 generates electric control actions coming in block 3, where they are converted into hydraulic control actions on the dispensers 4. The number of dispensers 4 depends on the number of FCC collectors and is determined as follows: one dispenser per collector. As an example, in the description and in the figure, the option of FCC with five collectors is selected.

The start of the FCC and the conclusion of the engine to the minimum afterburner mode is provided by the first dispenser and the first (starting) collector. When the pilot transfers the ore to the “minimum afterburner” platform, ER 2 provides:

- Calculation of the prescribed boost fuel consumption for the “minimum boost” mode;

- transfer of the first dispenser 4 to a position corresponding to a predetermined afterburner fuel consumption;

- opening of the first ZK 5;

- inclusion of the unit "firing track" (not shown).

After starting the FCC and the engine enters the “minimum boost” mode, ER 2 generates a signal to the pilot “Fast and the Furious On”.

When the pilot transfers the ore to the “maximum afterburner” position, ER 2 provides:

- Calculation of the prescribed fuel consumption of afterburning fuel for the "maximum boost" mode;

- distribution of a given consumption of afterburning fuel between the dispensers, depending on the throughput of the corresponding FCS fuel manifold dispenser;

- alternate inclusion in the work of the remaining four dispensers 4.

Moreover, when you turn on the work of the second dispenser 4 ER 2 provides:

- transfer of the second dispenser 4 to a position corresponding to the afterburner fuel consumption set for it;

- calculation of the time of filling the second collector with fuel (collector volumes are stored in the storage device ER 2 - not shown in the figure);

- the opening of the second ZK 5;

- transfer of the first dispenser 4 at the time of filling the second collector to a position corresponding to the afterburner fuel consumption set for it, increased by an amount corresponding to the volume of the second collector.

The translation is carried out evenly so that by the end of the filling time the flow will increase by the value of the collector volume.

At the moment of completion of filling the second collector with the command ER 2, the first dispenser 4 for the shortest possible time returns to the position corresponding to the boost fuel consumption set for it.

The inclusion of the remaining three dispensers is similar.

T.O. provides a smooth change in effective fuel consumption and, accordingly, a smooth change in engine thrust during the throttle response, i.e. improving the quality of work of self-propelled guns. The consequence of this is to increase engine reliability and aircraft safety.

Claims (1)

A method of controlling fuel consumption in a combustion chamber afterburner (FCC) of a gas turbine engine, which consists in the fact that the measured air temperature at the engine inlet, the air pressure behind the compressor, the gas pressure behind the engine turbine, the throttle position and the fuel consumption in the main combustion chamber (ACS) ) control the fuel consumption in the FCC, characterized in that, in addition, during the afterburner pickup, when the next FCC fuel collector is connected, the afterburner fuel consumption is increased through yduschy collector by the value of the next volume.

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