Launcher stage comprising a temporary support structure for temporarily supporting nozzle sections allowing access to the core of the engine

Abstract

A stage of a space launcher including an engine core, a tank secured above the engine core, and a nozzle including a first deployable nozzle section secured below the engine core, the nozzle further including a second and a third section configured to be situated extending from each other when the nozzle is in a deployed propulsion configuration. The stage further includes a structure for temporarily supporting nozzle sections mounted on the tank, configured to change the nozzle to a configuration for accessing the engine core wherein the nozzle sections are inserted into each other, with the third section bearing against a lower support of the temporary structure.

Claims

1. A stage of a space launcher comprising: in an upright position, an engine core, a tank secured above the engine core, and a deployable nozzle comprising a first deployable nozzle section secured below the engine core; the deployable nozzle further comprising a second nozzle section borne by a structure enabling deployment of the deployable nozzle, along with a third nozzle section; the first, second, and third nozzle sections are configured to be situated extending from each other when the deployable nozzle is in a deployed propulsion configuration, with the second nozzle section being situated extending from the first nozzle section, and the third nozzle section being situated extending from the second nozzle section, the second nozzle section bearing the third nozzle section; the stage further comprising a temporary support structure for temporarily supporting the nozzle sections mounted on the tank, the temporary support structure being suspended from the tank and being configured to change the deployable nozzle to a configuration for accessing the engine core wherein the first deployable nozzle section at least partially enters the second nozzle section, and wherein the second nozzle section at least partially enters the third nozzle section, wherein a lower end of the third nozzle section bears against a lower support of the temporary support structure; and the first, second, and third nozzle section are configured to be in a launch configuration in which an axial length of the deployable nozzle is reduced by raising the second nozzle section so that a lower end of the second nozzle section is axially situated approximately where an upper end of the first deployable nozzle section is secured to the engine core, the second nozzle section substantially blocking access to the engine core by encompassing the engine core in the launch configuration.

2. A stage according to claim 1, wherein, in the configuration for accessing the engine core, the lower end of the second nozzle section also bears against the lower support of the temporary support structure.

3. A stage according to claim 1, wherein, in the configuration for accessing the engine core, an upper end of each of the second and third nozzle sections is situated on a level with or below the upper end of the first deployable nozzle section connected to the engine core.

4. A stage according to claim 1, wherein the temporary support structure comprises rods connecting the lower support to the tank.

5. A stage according to claim 1, wherein the lower support is in a shape of a ring.

6. A stage according to claim 1, wherein the temporary support structure further comprises an upper support situated above an upper end of each of the second and third nozzle sections in the configuration for accessing the engine core.

7. A stage according to claim 6, wherein the temporary support structure further comprises a connection frame between the upper and lower supports, the connection frame being arranged around the third nozzle section.

8. A space launcher comprising at least one stage according to claim 1.

9. A method for manufacturing the space launcher including a main stage and an upper stage according to claim 1, the method comprising: producing the upper stage, by changing the deployable nozzle to the configuration for accessing the engine core; transporting the upper stage to a launch pad, with the deployable nozzle in the configuration for accessing the engine core; and on the launch pad, mounting the upper stage onto the main stage, with the deployable nozzle in the configuration for accessing the engine core.

10. A method for manufacturing the space launcher according to claim 9, further comprising, prior to a launch: placing the nozzle in a launch configuration, wherein the second nozzle section is arranged around the engine core, and the lower end of the second nozzle section bearing an upper end of the third nozzle section; and removing the temporary support structure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) This description will be made with reference to the appended figures wherein;

(2) FIG. 1 represents a schematic front view of a part of a launcher stage according to one preferred embodiment of the present invention, with the nozzle thereof in the launch configuration;

(3) FIG. 1a represents a perspective view of the part of the launcher stage shown in the previous figure;

(4) FIG. 2 represents a similar view to that in FIG. 1, with the nozzle in the deployed propulsion configuration;

(5) FIGS. 3 and 4 represent two perspective views, according to different angles, of the part of the launcher stage shown in the previous figures, with the nozzle thereof in the configuration for accessing the engine core thereof; and

(6) FIG. 5 represents a perspective view of a part of the launcher stage shown in the previous figures.

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

(7) With reference to FIGS. 1, 1a and 2, a part of an upper stage of a space launcher according to one preferred embodiment of the present invention is represented, the launcher being of the Ariane 5 type.

(8) The launcher stage 1, represented in the upright position, comprises an engine core 2 including in particular a combustion chamber wherein the reaction between liquid hydrogen and oxygen takes place, producing water vapour which is ejected at a high speed by the nozzle 4 situated below the engine core 2.

(9) The hydrogen and oxygen are contained in a tank 6 arranged above the engine core 2, the mechanical junction between these two elements being provided using a conical tank base, as shown in FIGS. 1, 1a and 2. The payload intended to be transported by the launcher is borne above the tank 6, on this upper launcher stage.

(10) To reduce the mass and size, the nozzle 4 has a deployable feature. It consists of three sections 8a, 8b, 8c, suitable for moving relative to each other along the axial direction 9 of this nozzle, corresponding to the vertical direction. Each of these sections adopts a generally tapered shape, so as to form a divergent nozzle together.

(11) In FIGS. 1 and 1a, the nozzle is represented in the launch configuration, whereas in FIG. 2, the nozzle is in the deployed propulsion configuration. These two configurations, which will be detailed hereinafter, are respectively adopted on the launch pad prior to launching, and during the mission after separating the upper stage and the main stage of the launcher.

(12) In the launch configuration shown in FIGS. 1 and 1a, the first nozzle section 8a is secured to the lower end of the engine core 2. This attachment is furthermore retained regardless of the configuration adopted by the nozzle. The first section 8a is thus projected downwards from the engine core 2.

(13) On the other hand, the second section 8b and the third section 8c adopt a raised position suitable for reducing the axial length of the nozzle 4. More specifically, the second section 8b is raised such that the lower end thereof is situated approximately at the level of the upper end of the first section 8a. It is borne by a structure 10 enabling the axial movement thereof. This structure 10, known to those skilled in the art, is secured to the first section 8a and to the tank 6 and/or to the engine core 2, by means of girders supporting a vertical rack 12 along which the second section 8b is slidably controlled electrically.

(14) The third section 8c is also held in the raised position, while being borne by the second section 8b. More specifically, these two sections are situated extending from each other, by adopting a relative position identical to that in the deployed propulsion configuration. A reversible mechanical connection known to those skilled in the art is provided between the upper end of the third section 8c and the lower end of the second section 8b, for example of the lock mechanism type.

(15) In this launch configuration adopted on the launch pad, the lower end of the third section 8c is situated approximately at the lower end of the first section 8a.

(16) While raised, the second section 8b encompasses a large part of the engine core 2. On the other hand, in the deployed propulsion configuration shown in FIG. 2, the sections 8b and 8c are lowered so as to be situated in line with the lower end of the first section 8a, so as to form a tapered nozzle, also referred to as divergent nozzle, of maximum length. This lowering is performed electrically using the rack 12, also with the third section 8c locked onto the second section 8b.

(17) In FIGS. 3 and 4, one of the specific aspects of the invention is shown, consisting of providing a structure for temporarily supporting sections to be able to change the nozzle 4 to a third configuration, or configuration for accessing the engine core.

(18) The temporary support structure 14 comprises a plurality of vertical rods 16, for example four, wherein the upper end is secured to the base of the tank 6. These rods, arranged about the engine core 2 and the nozzle sections 8a, 8b, 8c, also have a lower end fixedly bearing a ring-shaped lower support 18. This ring 18, having the axis 9, is envisaged to bear the third section 8c, supporting the lower end thereof. Contact is preferentially provided between the entire circumference of this lower end of the section 8c and the ring 18. In this way, the entire mass of this third section 8c is borne by the ring 18.

(19) Furthermore, the same may apply for the second section 8b, as represented in FIGS. 3 and 4. In this case, even if this section continues to be mechanically connected to the rack 12, the mass thereof is borne entirely or almost entirely by the ring 18.

(20) In this particular configuration, the sections enter into each other. More specifically, the first section 8a at least partially enters the second section 8b, whereas the latter at least partially enter the third section 8c. For an even more compact size, such as that shown, the three sections are inserted into each other while overlapping entirely, i.e. the upper ends thereof are situated substantially at the same first level, and the lower ends thereof are also situated substantially at the same second level. For this reason, in the specific configuration for the present invention, the reduced length of the nozzle is equivalent to a length of a single one of the three nozzles. As described above, the three sections 8a, 8b, 8c substantially have the same length along the axis 9, enabling a maximum compact size when inserted into each other, as shown in FIGS. 3 and 4.

(21) The temporary support structure 14 also comprises an upper support 20 borne by the rods 16 traversing same, this support adopting an identical shape to that of the lower ring 18. This ring covers the upper ends of the second and third sections 8b, 8c, contact even being optionally provided to increase the mechanical support of these sections. A connecting frame between the two rings 18, 20 may also be provided, for example in the form of smaller vertical rods 22 connecting the two rings, and a ring 24 interconnecting said rods 22 along with the longer rods 16.

(22) Although not shown, access steps and/or a tool storage compartment may be integrated in this structure 14, whereon operators can walk and/or secure themselves to perform operations on the engine core 2, the lateral access whereof has been entirely freed by lowering the sections 8b, 8c.

(23) Indeed, in this configuration, the entire engine core 2 is accessible for operators seeking to perform nominal or non-nominal operations on the launch pad, since all the sections 8a, 8b, 8c are situated below this core 2.

(24) This configuration may be adopted at the production output of the upper stage 1, and retained during the transport thereof on the launch pad. In this way, the sections 8a, 8b, 8c may be held mechanically in a very satisfactory manner by one or more elements of the temporary support structure, limiting the risk of damage thereof.

(25) Then, also while retaining this configuration, the upper stage 1 is mounted on the launch pad above a main stage 50 of the launcher 100, shown partially in FIG. 5. The lower support 18 is then situated at an abutment or slightly above a tank 56 of this main stage 50, with the engine core 2 revealed by the sections.

(26) Throughout the period prior to the launch, operations may thus be performed on the engine core 2, readily accessible to operators moving on the temporary structure 14. It is only before the gap between stages is sealed with a skirt 60, shown in FIG. 5, that the deployable nozzle 4 is moved to the launch configuration thereof represented in FIGS. 1 and 1a. For this purpose, the section 8b is preferably moved with the rack, until the locking thereof with the section 8c, and the temporary support structure 14 is then removed. The skirt 60 may then be installed.

(27) It is noted that preferentially, the entire structure comprises a sufficient degree of demountability so that an operator can obtain access via the flap for accessing between the stages, which is small in size.

(28) Obviously, various amendments may be made by those skilled in the art to the invention described herein, merely as non-limiting examples.