DE2429951A1 - DEVICE FOR FUEL INJECTION - Google Patents

Description

Device for fuel injection

The invention relates to a device for fuel injection especially for jet engines, where a medium, fuel containing, annular flow is guided and stretched between an inner and an outer air stream, which be set in rotation by vane arrangements for swirling.

According to the invention, the mean annular flow is passed through a mixture formed from air and fuel, and it is in turn rotated by a third swirling vane arrangement, for example with helical ribs.

Ia further embodiment of the invention, the shear action, which the inner and outer air flow on the fuel contain

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tend to exercise a middle current carried between them, thereby increases that the blades of the inner and outer blade arrangement for swirling are given different angular distances in the direction of rotation, wherein the outer vane arrangement advantageously has a smaller angular spacing of the vanes than the inner vane arrangement having.

In one embodiment of the invention, these are different Parts of the device combined into two sub-units, which can be slid against each other and each attached separately to different parts of the combustion chamber of the jet engine are. Preferably, the joint between the two subunits, which allows displacement, is used in the blade arrangement provided for swirling, which is used to set the outer air flow in rotation. For this purpose, the outer circumference is on the inner circumference Blade arrangement arranged for swirling a sliding bush.

In the following the invention is based on an exemplary embodiment explained with reference to the accompanying drawing. It shows:

Fig. 1 is a transverse section through the inventive Fuel injection device taken along line I-I of Fig. 2;

2 shows a longitudinal section through the device according to the invention for fuel injection along the line II-II of Fig. 1;

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Fig. 3 is a schematic exploded view of the invention Fuel injection device;

4 shows a longitudinal section through a device according to the invention for fuel injection, its attachment in the Combustion chamber of a jet engine is shown. ^

The device for fuel injection shown in FIGS. 1 and 2 has an outer sleeve 1 and a concentrically arranged one
inner sleeve 2, which between them form an annular outer passage 3, which in the direction of the arrows Fl of air
is traversed, which is set in rotation by an outer swirler 4. A centered, profiled mandrel 5 delimits along with a concentric between it and
the inner sleeve 2 arranged sleeve 6 an inner passage 7, where in the direction of the arrows F2 flowing primary air is set in rotation by an inner swirler 8. The fuel will be the
Device for fuel injection fed through a nozzle 9 which opens into an annular inlet manifold Io. That
The air / fuel mixture flows into an annular space 11, which is delimited by the sleeves 2 and 6, between which a
third, middle swirler 12 is arranged, through which the
Air / fuel mixture flowing in the direction of arrows F3 in
Rotation is offset.

In the exploded view of FIG. 3, in which a Device according to the invention for injecting fuel onto others

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Art is shown, you will find the same parts as those described above.

The outer passage 3 is located between the outer sleeve and the sleeve 2. The two sleeves are through the paddles of the outer Verwirblers 4 firmly connected to each other. The sleeve is made of a ring 13 covered, and it carries at its lower part an inlet pipe 14 for the air / fuel mixture.

The middle passage 11 is located between the sleeve 2 and the sleeve 6, which ends in a conical ring 15. The sleeve carries the central swirler 12, which has helical ribs 16 and a half-ring 17 is formed, which deflects part of the air / fuel mixture before the helical Ribs 16 reached, so that the rotation of the mixture accelerated and its mixing is improved.

The inner passage 7 is arranged between the sleeve 6 and the inner mandrel 5; this carries the blades of the inner swirler 8th.

The arrangement is covered by a ring 18 which between its inner edge and the ring 13 leaves an annular gap 19 free.

The fuel is injected into the inlet pipe 14 at 9, which

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ches is in turn pressurized with air. The air / fuel mixture then passes to the annular intake manifold and is then divided into two streams: one flows directly between the helical ribs 16, the other flows around the half-ring 17 shown as a half-ramp before it reaches the helical ribs. The air / fuel mixture becomes ejected through an annular gap 2o which is left free between the rings 13 and 15. The one from the outer swirler 4 air set in rotation flows through the annular gap 19 off, while the rotated by the inner swirler 8 Air is expelled through a central opening 21.

Line device according to the invention for fuel injection, such as it is shown in Figures 1 and 2 can advantageously be mounted in the manner shown in Figure 4. With this attachment the outer sleeve 1 belongs to an outer sub-unit A and is screwed directly onto the bottom 22 of the combustion chamber. She knows a shoulder on its rear part, on which a heat shield 2f is welded and on its front part it is threaded 25 provided. A threaded ring 26 can be attached to the thread 25 and holds the sleeve 1 firmly to the base 2 2 pressed against the combustion chamber. The sleeve 1 carries on its inside at the same time the outer swirler 4, the inner circumference of a Socket 2 7 carries.

In this outer subunit A there is an inner subunit Bfeinge-

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leads, which is formed by the sockets 2 and 6, the inner swirler 8, the middle swirler 12, the mandrel 5 located in the middle and the inlet pipe I ¹ +, in the interior of which the nozzle 9 is arranged, which is supported by a support arm 28 is supplied with fuel. The sub-unit B, which is firmly connected to the support arm 28, can be inserted into the housing 29 of the combustion chamber via a corresponding hole 3o which is closed by a plate 31 which is firmly connected to the support arm 28 and by screws 32 on the housing 29 of the combustion chamber is attached.

The outer swirler 4 inserted in the sub-unit A is related to the sub-unit B independently, which facilitates the assembly and maintenance of the device. In operation, the sub-unit A heats up very much and expands, while the sub-unit B is cooled by the flow of the air / fuel mixture. The necessary play is obtained by sliding the sleeve 2 and the bush 27 against each other. It is enough to disassemble the Remove screws 32 in order to be able to pull out the inner sub-unit B through the hole 3o.

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Claims (5)

Claims / 1.) Device for fuel injection, especially for jet engines, in which a mean, fuel-containing, annular flow is guided and stretched between an inner and an outer air flow, which are set in rotation by vane arrangements for "swirling," characterized in that the middle , ring-shaped flow is formed by a mixture of air and fuel and is in turn set in rotation by a third blade arrangement for swirling, that the above-mentioned parts of the device are combined in two sub-units (A, B) which can be slid against each other and are each attached separately to different parts of the combustion chamber. 2. Apparatus according to claim 1, characterized in that 409-883 / 1 007 Sliding area between the two sub-units (A ₃ B) is provided on that blade arrangement (4) which is used to set the outer air flow in rotation. 3. Apparatus according to claim 2, characterized in that the inner A sliding bushing (27) is arranged around the outer scoop arrangement (4). 4. Device according to one of claims 1 to 3, characterized that the blades of the inner blade arrangement (8) and the outer blade arrangement (4) are different in the direction of rotation Have angular distances. 5. Apparatus according to claim 4, characterized in that the Angular spacing of the blades of the outer blade arrangement (4) is smaller than that of the blades of the inner blade arrangement (8th). 409883/1007