RU2509910C1 - Device for chemical firing of propellant components in liquid-propellant rocket engine - Google Patents

Abstract

FIELD: engines and pumps.SUBSTANCE: proposed device comprises cylindrical pipe with cylindrical ampoule filled with starting fuel fitted therein and clamped by shutoff valve screwed in pipe body. Said ampoule consists of cylindrical body, membrane assemblies at its inlet and outlet, said membranes being tightly secured along body edges and can be broken by working fluid. Shaped adapter is fitted at pipe inlet to decrease cavity air volume at ampoule inlet to its minimum. Pipe body inlet is fitted via angle piece directly at gas generator head. Said pipe is mounted in gas generator at position approximating to vertical. Supporting fluoroplastic rings are fitted between starting ampoule, shutoff valve and pipe jointly with rubber seal rings. Drain openings are made at ampoule inlet edges and pipe body. Angle pieces are welded to pipe body to support drain pipes. Baffles with filling and drain devices are spaced apart inside said ampoule and feature minimum axial overall dimension and cross-section area. Note here that filling device is arranged at the boundary of starting fuel zone and inert gas pad. Baffles are spaced apart inside said ampoule and feature minimum axial overall dimension and cross-section area. Note here that helical springs with bent-off lock rings are fitted in piston ends.EFFECT: fast, reliable and multiple firing.7 cl, 7 dwg

Description

The invention relates to liquid rocket engines and can be used for installation at the entrance to the mixing head of the rocket engine assembly for chemical ignition of fuel components.

A known ampoule with starting fuel for igniting the components of a liquid propellant rocket engine (LRE), which contains a cylindrical body, two membrane units installed in it, the membranes of which are hermetically fixed inside the body along its periphery from the input and output sides with the possibility of their breaking by the working medium. Each of the membrane nodes is made in the form of a piston equipped with a shank, a guide sleeve and ribs. The piston is connected to a membrane made in the form of an annular jumper (RF Patent No. 2159353C1 class 7 F02K 9/95 of 11/20/2000).

The disadvantages of the known ampoules with starting fuel include:

- significant axial dimensions of the membrane assemblies, made in the form of a piston with a shank of the guide sleeve and ribs, in connection with which there are void volumes in the ampoule at the inlet and especially at the outlet, which, after breaking through the membranes, must be filled with starting fuel, which lengthens the engine starting process due to more slow intake of fuel into the combustion chamber or gas generator (GG);

- the combined location of the starting fueling agent ampoule refueling means and the drain means in the same partition of the body causes a slight increase in the hydraulic resistance of the tract, and therefore, to reduce it, there is a need to increase the diameter of the passage section of the ampoule and its body, which entails an increase in the mass of the trunk body, in which is inserted into the ampoule;

- the absence of drainage holes at the entrance to the ampoule for displacing the air volume to its periphery and subsequent discharge into the atmosphere. The presence of air volume between the starting fuel and the main component impairs the quality of the starting fuel combustion process in the rocket engine units.

Known ampoule with starting fuel for ignition of the fuel components of the liquid propellant rocket engine, comprising a housing with an inlet and an outlet, two membrane assemblies, the membranes of which are hermetically fixed around the periphery in the housing from the inlet and outlet sides ("Design and Design of the LRE", edited by G. G Gahuna, Engineering, 1989, p.75, fig. 4, 5, prototype). Here, in the fuel pipeline, a “volume” is separated or allocated, separated by breakthrough membranes from the rest of the pipeline. This volume is filled with starting fuel, which spontaneously ignites with the oxidizing agent used in the engine.

The main disadvantages of the known technical solutions are the following:

- the presence of void volumes at the inlet and outlet of the ampoule (sinuses, cavity cavities, etc.) as a result of which the engine starting process is lengthened, the quality and reliability of fuel combustion are reduced;

- a single start, after which, for restarting the engine, the ampoule and membrane units must be cut out of the lines, replaced with new ones and welded again, which complicates the recharging process;

- the absence of a durable housing (tube) into which an ampoule with starting fuel is inserted causes a need for an increase in the thickness of its walls and mass when installed in high-pressure lines of a working medium (about 600 kg / cm2 or more).

The objective of the proposed technical solution is to reduce the time, improve the conditions and increase the reliability of ignition of the fuel components of a liquid rocket engine (LRE), as well as ensure the multiple use of the device.

The task is achieved in that:

- a device for the chemical ignition of fuel components in a liquid propellant rocket engine contains a cylinder made of a cylindrical one, into which an ampoule with a starting fuel is inserted into a cylindrical shape, drawn up by a shut-off valve screwed into the barrel body and consisting of a housing, membrane units at the membrane inlet and outlet of which are hermetically fixed around the periphery of the housing ampoules with the possibility of tearing them with a working medium, while at the entrance to the tube a profiled adapter is installed that reduces the void volume with air at the entrance to the ampoule to a minimum;

- the case of the tube with its output is installed through a square directly on the head of the gas generator;

- the tube is installed and fixed on the gas generator in a position close to vertical;

- between the starting ampoule, the shut-off valve and the tube, together with the rubber sealing rings, supporting rings of fluoroplastic are installed;

- drainage holes are made around the periphery at the entrance to the ampoule and in the case of the tube, and elbows are welded on the case of the tube to connect drainage pipelines;

- in the ampoule with starting fuel, the partitions with refueling and drain devices are spaced apart along the length of the ampoule and are made with the minimum axial overall dimensions and the cross-sectional area, while the refueling device is installed on the border of the zones of starting fuel and inert gas pad;

- in the ampoule with starting fuel, the membrane units are made with the smallest axial overall dimensions, while spiral springs with bent retaining rings are installed in the piston shanks.

Figure 1 shows the layout of a device for chemical ignition of fuel components in a gas generator connected to a turbopump unit (TNA).

Figure 2 shows a longitudinal section of a device for chemical ignition of fuel components.

Figure 3 shows the tube ampoules GG.

Figure 4 presents a longitudinal section of an ampoule with starting fuel, consisting of the following main parts and assembly units, where:

1 - a device for chemical ignition of fuel components;

2 - square;

3 - gas generator;

4 - turbopump unit;

5 - fitting for drainage of the air bubble;

6 - tube ampoules of a gas generator (GG);

7 - ampoule with starting fuel;

8 - case;

9 - shut-off valve;

10 - squib;

11 - ampoule body;

12 - membrane nodes;

13 - a pipe;

13a — membranes;

14 - profiled adapter;

15 - rubber sealing rings;

16 - fluoroplastic rings;

17 - drainage holes;

18, 18a - drainage holes;

19 - purge holes.

20 - drainage squares;

21 - partition walls;

22 - refueling device;

24 - starting fuel zone;

25 - zone of pillows with inert gas;

26 - drain device;

27 - a piston;

28 - a piston shaft;

29 - spiral spring;

30 - collector of air drainage;

31 - collector drainage mixture of air with fuel;

32 - collector for supplying fuel to the GG;

33 - outlet fitting “G” to the gas generator;

34 - a partition;

35 - pipeline;

h is the gap between the ampoule with starting fuel and a profiled adapter;

A - the gap between the tube and the starting ampoule;

T is the end face of the profiled adapter;

l is the length of the fitting;

P1 - cavity of the ampoule with neutral gas;

P2 - the cavity between the ampoule and the shut-off valve.

A device for chemical ignition of the fuel components 1 using a square 2 and fastening is installed on the gas generator 3 (Fig. 1), which is connected to the TNA 4. For the drainage of a gas bubble on the device body, a fitting 5 is welded.

A device for chemical ignition 1 (Fig. 2) contains a tube of a gas generator (GG) ampoule 6 of a cylindrical shape in which an ampoule with a starting fuel 7 is inserted in a cylindrical shape, pressed by a shut-off valve 9 screwed into the housing 8 (Fig. 3) (Fig. 2) )

In the shut-off valve 9 mounted igniter 10 to ensure its operation.

An ampoule with starting fuel (Fig. 4) 7 consists of a housing 11, membrane units 12 at the inlet and outlet, membranes 13 of which are hermetically fixed around the periphery of its housing.

At the entrance to the tube of the ampoule of the gas generator (GG) 6, a profiled adapter 14 is installed (Fig. 3), and a pipe 13 is welded between it and the casing 8.

To drain the air bubble from the tubes 6 of the device 1 is installed and mounted on the gas generator 3 in a position close to vertical.

Between the ampoule with the starting fuel 7, the shut-off valve 9 and the tube 6 are installed rubber o-rings 15 and the fluoroplastic rings 16 supporting them (Fig. 2).

For drainage of the air-combustible mixture at the periphery at the inlet of the ampoule 7, drainage holes 17 are made (Fig. 4), and in the housing 8 of the tube 6 there are drainage holes 18, 18a, a purge hole 19 (Fig. 3). On the housing 18 of the tube 6, drainage corners 20 are welded to connect drainage pipelines to them.

In the ampoule with starting fuel 7, the partitions 21 of the housing 11 are spaced apart in length to increase the volume of starting fuel and are made with a minimum axial and overall dimensions to reduce the weight of the ampoule.

The refueling device 22 is installed at the boundary of the starting fuel zone 24 and the inert gas pad zone 25. The drain device 26 is located at the bottom of the ampoule, taking into account the space for the piston stroke 27.

Membrane units 12 are made with minimum axial dimensions to reduce the ampoule length, while in the shanks 28 of the pistons 27 (Fig. 4) spiral springs 29 are installed with bent retaining rings to hold the pistons 27 in extreme positions after the membrane 13a has been burst from the pressure of the starting fuel. For the direction of stroke of the pistons 27 are partitions 34.

For the organization of drainage and supply of fuel to the gas generator between the housing 8 of the tube 6 (Fig.2), the starting fuel ampoule 7 and the shut-off valve 8, the collectors 30, 31, 32 are made.

At the output of the starting fuel from the casing of the tube 6 (figure 2) to the gas generator there is a fitting outlet "G" 33.

To the entrance to the tube 6 of the ampoule of the gas generator is connected a pipeline for supplying the main component "G" to the gas generator.

Between the ampoule with starting fuel (FIG. 2) and the shaped adapter 14, a minimum clearance h is provided, taking into account the technological allowances for the parts and the shrinkage of the material in the welds.

The air is removed from the volume between the profiled adapter 14 and the ampoule with starting fuel 7 through the cavity formed between the tube 6 and the ampoule (clearance A). The fitting 33 of the output "G" to the gas generator 1 is made of a minimum length to reduce the transit time of the fuel.

To compensate for temperature changes in the volume of starting fuel in the ampoule, a cavity P1 with a neutral gas is provided (Fig. 4).

Between the ampoule with the starting fuel 7 and the shut-off valve 9 there is a cavity P2, from which the air-fuel mixture is drained through the hole 18a before the gas generator is started.

A device for chemical ignition of fuel components in a rocket engine works as follows (see figure 1).

Fuel under pressure from the TNA through the regulator (not shown in FIG. 1) enters the cavity “P” at the entrance to the tube 6 of the GG ampoule (see FIG. 2) through a profiled adapter 14.

The adapter with its end face T enters the ampoule with the starting fuel 7, without blocking its drainage holes 17. Filling the cavity “P”, the fuel pushes the air bubble inside it through the drainage holes 17 into the gap A between the tube 6 and the ampoule with the starting fuel 7.

Since the tube 6 is installed in a position close to vertical, the air bubble, passing through the space formed by the gap A, enters the manifold 30, then into the nozzle 5 and is drained through the pipelines connected to it, Fig. 1 is not shown) to the bench system during ground engine tests or into the engine drainage system in flight. A further increase in pressure at the entrance to the ampoule with starting fuel causes the membrane 13a to rupture (see Fig. 4) and the piston 27 is shifted all the way to the baffle 34. The bent ends of the coil spring 29 that are freed up at the same time diverge to the sides and engage on the end face T1, not allowing the piston 27 to reverse movement towards the flow under the influence of flow shock. With further movement of the fuel, pressure builds up in the ampoule with starting fuel 7, which leads to the compression of neutral gas in the “P ₁ ” cavity (zone 26), after which the membrane 13a of the membrane assembly 12 breaks out at the outlet of the ampoule and the piston 27 is shifted to the stop to the partition 34.

A unitary, one-component starting fuel that ignites on contact with air enters the manifold 32 between the shut-off valve 9 and the housing 8 of the cylinder tube 6 of the GG ampule, and since the valve is in the open state at the start of the generator gas, the starting fuel then goes to the gas generator 3, where it is connected with air, it ignites spontaneously, burns, and creates favorable conditions for the combustion of fuel components (oxidizer and fuel) entering the IT chamber. In addition to the drainage of the gas bubble through the nozzle 5 of the GG tube, as the collector 30 passes through the gap between the tube and the ampoule body, the mixture of air and fuel is drained through the hole 18 (see Fig. 3) and the drainage angle 20 “DG1” and the connected pipeline into the common a box of drains (not shown in FIG. 1). Through the hole 18a in the casing of the tube 6 and the square 16 "DG2" air is drained, which is in the manifold 31 and the cavity P2 between the ampoule of the starting fuel 7 and the shut-off valve 9, which is discharged through the connected pipeline (not shown in Fig. 1) into a common drainage box . The above measures for the drainage of air bubbles, fuel mixtures with air are aimed at ensuring the uniformity and high quality of starting and working fuel entering the gas generator, i.e. without air inclusions, which is positive for the combustion of fuel components without frequencies and vibrations. The maximum approximation of the end face T of the shaped adapter 14 to the ampoule with starting fuel (gap h is 5 mm) at its inlet, shortening of the pipe 35 (see Fig. 1) and reducing the length of 1 fitting 33 (see Fig. 2) at the outlet of the housing tubes 6 on the GG to a minimum value can reduce the attached volumes, which reduces the time of entry of starting fuel into the gas generator and intensifies the process of ignition of fuel components in it.

Reducing the length of the two partitions 21, as well as the axial overall dimensions of the membrane assemblies 12, made it possible to increase the amount of starting fuel to be filled into the ampoule 7, which in the device was increased by 1.5–2 times compared with the minimum required for igniting the fuel components. Such an increase in the amount of starting fuel has a positive effect on increasing the reliability of their ignition in the chamber of the gas generator.

The installation of fluoropolymer rings 16 near the rubber rings 15 eliminates the destruction of the former and their forcing into the slot gap between the tube and the shut-off valve, i.e. increases the reliability of the seals and improves the tightness of the joints.

The reduction of the bore holes D (see FIG. 4) to the required value allowed to reduce the diametrical dimensions of the partitions 21, the housing 11, the membrane nodes 12, which ultimately led to a decrease in the mass of the ampoule, tube and the device as a whole.

The ampoule is charged with starting fuel in its vertical position (zone 24) to the refueling device 22, then neutral gas is injected into the cavity P ₁ , which compensates for volume changes of the starting fuel depending on the ambient temperature and, thereby, prevents the ampoule from breaking internal pressure.

The use of a spiral spring 29 with folding rings increases the reliability of the membrane nodes after they are triggered, because provides for the retention of the pistons 27 in a shifted state and the constancy of the areas of the passage sections of the partitions 34 at the input and output of the ampoule with starting fuel.

The proposed device for chemical ignition of fuel components in a liquid propellant rocket engine is multiple when it is used in the fire bench testing of liquid propellant rocket engines, because provides the possibility of reloading with new ampoules with starting fuel after dismantling the spent ampoules, flushing, purging the cavities and replacing the O-rings of single use.

Claims (7)

1. A device for the chemical ignition of fuel components in a liquid propellant rocket engine containing a cylinder made of a cylindrical one, into which an ampoule with a starting fuel is inserted in a cylindrical shape, drawn up by a shut-off valve screwed into the tube body and consisting of a body, membrane units at the inlet and outlet, the membranes of which are hermetically fixed along the periphery of the ampoule body with the possibility of tearing them with a working medium, characterized in that a profiled adapter is installed at the entrance to the tube, which reduces the void volume with air at the entrance to the ampoule to m the least. 2. The device according to claim 1, characterized in that the housing of the tube with its output is installed through a square directly on the head of the gas generator. 3. The device according to claim 1, characterized in that the tube is installed and mounted on the gas generator in a position close to vertical. 4. The device according to claim 1, characterized in that between the starting ampoule, the shut-off valve and the tube, together with the rubber sealing rings, supporting rings of fluoroplastic are installed. 5. The device according to claim 1, characterized in that along the periphery at the entrance to the ampoule and in the casing of the tube drainage holes are made, and on the casing of the tube angles are welded to connect the drainage pipelines. 6. The device according to claim 1, characterized in that in the ampoule with the starting fuel, the partitions with refueling and drain devices are spaced along the length of the ampoule and are made with minimum axial overall dimensions and the area of the passage sections, while the refueling device is installed on the border of the zones of the starting fuel and inert gas cushions. 7. The device according to claim 1, characterized in that in the starting ampoule the membrane assemblies are made with minimum axial overall dimensions, while spiral springs with bent retaining rings are installed in the piston shanks.

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