DE102008020198A1 - Nozzle extension for rocket engine, has nozzle cover provided with two shell elements made of ceramic fiber reinforced composite material, where shell elements are fixed relative to each other - Google Patents

Abstract

The extension (10) has a nozzle cover (18) limiting a flow cross-section (24), which is extended from a nozzle extension inlet (14) to a nozzle extension outlet (16). The nozzle extension inlet is connected with a combustion chamber outlet of a combustion chamber of an engine. The nozzle cover comprises two shell elements (26, 28) made of a ceramic fiber reinforced composite material, where the shell elements are fixed relative to each other. The shell element (26) limits an interior space (22), and the composite material is carbon/silicon carbide material. An independent claim is also included for a method for producing a nozzle extension for an engine.

Description

The The present invention relates to a nozzle extension for an engine, especially for a rocket engine, with a nozzle shell having a flow cross-section bounded by a nozzle extension input extended to a nozzle extension output, wherein the nozzle extension input with a combustion chamber outlet a combustion chamber of an engine is connectable.

From the US 6,467,253 B1 a nozzle structure for rocket nozzles is known. This nozzle structure comprises a nozzle wall which is composed of a plurality of wall parts which extend from an inlet to an outlet of the nozzle structure and are longitudinally interconnected.

Of the The present invention is based on the object, a nozzle extension to create an engine that is lightweight, stable and is thermally highly resilient.

These Task is at a nozzle extension of the aforementioned Art solved by the fact that the nozzle casing at least two made of a ceramic fiber composite, relative Having each other fixed shell elements.

Of the multi-shell construction of the nozzle extension allows to provide a mechanically stable nozzle extension, which is characterized by a high bending and torsional rigidity. hereby can the nozzle extension withstand high side loads, which in particular by unsymmetrical detachment of a Nozzle flow in the area of a nozzle inner wall arise.

The inventive nozzle extension allows the use of thin-walled shell elements, which only have a low weight and thus contribute to the overall efficiency of a Engine to increase.

The inventive nozzle extension is thermal highly resilient, so they are in one compared to conventional ones Nozzle extensions operated at higher temperature windows can be. This reduces the requirements for an if necessary provided cooling of the nozzle extension, so This also increases the overall efficiency of the engine is reached.

in the Frame of the present invention is under a shell element a component understood from the nozzle extension input or adjacent to it to the nozzle extension output or adjacent thereto extends and in particular a peripherally has closed profile. The nozzle jacket can in Double shell, triple shell or multiple shell construction executed be.

Preferably are at least two, preferably all shell elements the nozzle shell of at least one ceramic fiber composite material (CMC material, "Ceramic Matrix Composite") produced. Also a hybrid construction using different ceramic Fiber composites for a shell element and / or for different shell elements is possible.

Preferably the nozzle extension comprises a first shell element, which limits a nozzle extension interior. This enables the provision of a thermally highly stable shell element in a nozzle shell section, which is the highest is exposed to thermal stress.

To An advantageous embodiment of the invention is at least a portion of the first shell member fluid permeable. This allows a cooling fluid in the direction to pass on the nozzle extension interior through the first shell element. This cooling fluid forms at the boundary of the nozzle extension interior a boundary layer film, which flows through the nozzle extension Hot gases from the shell element shields and the convective Heat transfer from the nozzle extension interior reduced in the nozzle casing. When using a liquid cooling fluid an additional cooling effect is achieved by that the cooling fluid evaporates while latent heat receives. This type of cooling is also called effusion or Transpirationskühlung referred to, as effusion cooling usually a sweat cooling without phase transition and as Transpiration cooling a sweat with Phase transition is called.

Advantageous it is further, if at least a portion of the first shell element is porous. This allows a particularly lightweight To produce shell element, which is mechanically stable. The Porosity of the first shell element allows beyond that, in a simple way a fluid-permeable To provide ("permeable") first shell element, which is an effusion or transpiration cooling of the first shell element allows.

Advantageously, the nozzle extension comprises a second shell element, which limits the nozzle extension to the outside. This allows the provision of a shell element, which also in a thin-walled construction a provides high area moment of inertia.

To an embodiment of the invention, the nozzle casing at least a third shell element, which between a arranged first shell element and a second shell element is. Such a third shell element makes it possible further stiffen the nozzle casing and / or between the individual shell elements arranged cavities voneinan the to separate. These cavities, for example used for flow with a cooling fluid become.

Preferably At least a portion of the third shell element is fluid-permeable and / or porous to a flow through the third shell element to allow with a cooling fluid.

Especially it is preferred if the third shell element at least two Shell member sections which, in a direction from the nozzle extension entrance following each other on the nozzle extension exit are arranged. These shell element sections can different in terms of their fluid permeability and / or porosity Have properties such that a pressure profile and / or a flow rate a cooling fluid flow can be influenced.

Preferably is at least one shell element at least partially with a fluid barrier layer provided. Such a fluid barrier prevents in their effective range the entry of a cooling fluid in a shell element or the exit of a cooling fluid from a shell element.

Especially it is preferred if the fluid barrier layer has at least one fluid passage opening. This allows in the region of the fluid passage opening the entry of a cooling fluid into a shell element or the exit of a cooling fluid from a shell element. Preferably, a plurality of fluid passage openings are provided, which are distributed over the fluid barrier layer and thus a locally adapted entry of a cooling fluid in a Bowl element in or outlet of a cooling fluid from a Enable shell element out.

in principle It is possible that the at least two shell elements and optionally at least a third shell element of the same Material or made of different materials. in this connection it is particularly advantageous if that for the ceramic Fiber composite used fiber material contains carbon fibers. However, it is also advantageous fiber material of SiC, SiBNC, SiCN and / or oxide ceramics.

When Matrix material is advantageously used carbon, which for increasing the oxidation resistance can be silicided. It can also oxide ceramic matrix materials be used.

In Advantageously, the fiber composite material is a C / C material, a C / SiC material or a C / C-SiC material.

To An advantageous embodiment of the invention is at least one of the shell elements in one piece. This can be a Nozzle jacket can be created with a particularly simple structure.

A sees further advantageous embodiment of the invention in that at least one of the shell elements is single-layered. This also allows a nozzle shell with a simple Construction are created.

To a further advantageous embodiment of the invention it is provided that at least one of the shell elements is multi-layered. A multi-layered construction of a shell element allows it to provide a dimensionally stable sandwich component.

Advantageous it is also, if at least two shell elements together are integral. Such a nozzle extension can be produced in a particularly simple manner.

Especially it is preferred if at least two shell elements to each other are spaced. The distance of the shell elements causes an increase the area moment of inertia of the multi-skin Nozzle jacket. Furthermore, by the at least two shell elements a cavity limits the who, for example, to the flow can be used by means of a cooling fluid.

It is particularly preferred if the distance between the at least two shell elements, starting from the nozzle extension input, decreases in the direction of the nozzle extension exit. In the region of the nozzle extension input or adjacent thereto, a particularly high area moment of inertia can be provided. In the region of the nozzle extension output or adjacent thereto, a nozzle shell with a low shell thickness can be provided. The reduction of the distance between the shell elements is also very advantageous if the cavity formed between two shell elements is used to flow through with a cooling fluid. In this case, a pressure gradient can be generated, which is the transport of a cooling fluid in the direction supported on the nozzle extension output.

Preferably the nozzle extension comprises at least one support device, by means of which at least two shell elements relative to each other can be fixed and / or spaced. This can be a special stable nozzle shell are provided. The support device can in particular in the form of at least one support rib, which the shell elements in the radial direction relative to each other supports, be trained. Such a support rib can also be called a "stringer" and Can also be used as a limiting element for a cooling channel be used. The support means can "in situ "together with the at least two shell elements getting produced. The support device can also be separated made and glued with at least one shell element or thermally be joined, for example by laser insertion.

To a particularly advantageous embodiment of the invention At least two shell elements are interconnected by means of connecting fibers. In this way, a particularly lightweight and stable composite be created from at least two shell elements, in particular when these shell elements are spaced from each other. After a particularly advantageous embodiment of the invention at least two shell elements by means of connecting fibers with each other sutured. This allows it as the connecting elements acting connecting fibers in a simple manner with the fiber structures to connect the shell elements.

Preferably is at least a part of the connecting fibers around Carbon fibers. These have a very high tensile strength. This is particularly advantageous if two spaced apart shell elements Limitations for one with pressure (for example in height of 80 bar) to form charged cooling fluid. The one by one Cooling fluid to the shell elements exerted pressure forces can then compensated by appropriate tensile stresses of the connecting fibers become.

Preferably the nozzle extension comprises at least one cooling fluid space to flow through with a cooling fluid. this makes possible an active cooling of the nozzle extension, which it allows the nozzle extension at higher temperatures to be able to operate, as with only radiation-cooled Nozzle extensions is the case. The cooling fluid space may include a plurality of cooling fluid channels, which a straight or a curved or spiral Have history.

Preferably is the cooling fluid space between at least two shell elements arranged. As a result, by a spacing of two shell elements resulting cavity can be used optimally.

Preferably the nozzle extension comprises a feeder for the supply of the cooling fluid in the Cooling fluid space. Such a feeder comprises in particular a cooling fluid distributor, which makes it possible supplied from one or more cooling fluid conduits Cooling fluid in an annular cooling fluid space feed.

Preferably the feeder is located at or adjacent to the nozzle extension entrance. This allows the nozzle extension in one To cool thermally stressed area.

Preferably the nozzle extension comprises a discharge device for the discharge of the cooling fluid the cooling fluid space. This allows a controlled Exit of the cooling fluid out of the nozzle shell.

Preferably the discharge device is at or adjacent to the nozzle extension exit arranged. This allows one at least approximately complete cooling of the nozzle shell and also has the advantage that the cooling fluid in the range the nozzle extension output from the nozzle shell can flow out and thus the pulse of the nozzle extension strengthened. This makes it possible to create a kinetic Energy of the cooling fluid to use, so that the overall efficiency an engine can be increased.

Preferably the nozzle extension comprises at least one sealing device for sealing the cooling fluid space to the outside, in particular radially outward. This way you can unwanted escape of the cooling fluid from the Cooling fluid space can be prevented radially outward.

To An embodiment of the invention is at least one Shell element effective as a sealing device. Such a shell element is made of a fluid-impermeable material.

According to a further embodiment of the invention, at least one sealing device is provided separately from a shell element. This makes it possible to produce a shell element made of a fluid-permeable material arranged radially on the outside relative to a cooling fluid space. The separately provided sealing device can be formed for example in the form of a metallic or ceramic additional layer, which forms a diffusion barrier, the outlet of fluid, ie liquid and / or gas, radially outward prevented. Such an additional layer may, for example, be applied in a gas flow sputtering process or in a cold gas sputtering process. Furthermore, a galvanic application or even a plasma coating, in particular a pyrocarbon, is possible.

To An embodiment of the invention is the at least a sealing device in the form of a gaseous barrier layer provided. Such a barrier layer has a particularly good Sealing effect on.

To An embodiment of the invention is the cooling fluid to a fuel, in particular a Fuel. These are, for example, liquid or gaseous hydrogen, methane or kerosene. The Use of a fuel as a cooling fluid has the advantage that no separate cooling fluid storage for storing a Cooling fluid must be provided.

To a particularly advantageous embodiment of the invention the cooling fluid is a turbine exhaust gas. Due to the very high temperature resistance of the nozzle extension according to the invention, which is made of a ceramic fiber composite material, a cooling fluid can be used which during of the pass through a turbine has already been heated. The turbine exhaust gas may be, for example, superheated steam act, which is generated by a gas generator.

Preferably the turbine exhaust gas is taken from a fuel delivery system. In such conveyors turbines are used to To drive pumps which fuel a combustion chamber of the engine and / or oxidizer under a high pressure.

Preferably the nozzle extension comprises at least one connecting device for connecting the nozzle extension with a combustion chamber device. This allows the nozzle extension and the Manufacture combustion chamber device as separate assemblies and then connect with each other.

For a stable connection between the nozzle extension and the combustion chamber device, it is advantageous if the connecting device a first connecting portion, which with at least a shell element cooperates, in particular with a shell element, which limits the nozzle extension to the outside. On This way, the connecting device can be in a thermally low loaded area of the nozzle extension can be arranged.

Further it is preferred if the combustion chamber device has an outer wall and when the connecting device has a second connecting section includes, which cooperates with the outer wall. hereby the connection between the combustion chamber device and the Connecting device in a thermally low loaded area the combustion chamber device.

The The invention further relates to a method for producing a nozzle extension for an engine, especially for a rocket engine.

Of the The invention is based on the further object of a method for To provide a nozzle extension, which is easy, stable and thermally highly resilient.

These The object is achieved according to the invention that at least two shell elements of a nozzle shell be made of a ceramic fiber composite material.

Special Embodiments and advantages of the invention Some of the procedures have already been mentioned above the particular embodiments and the advantages of the invention Nozzle extension has been explained and is hereby incorporated by reference referenced.

In Advantageously, to produce a nozzle extension a first fiber structure for a first shell element and a second fiber structure for a second shell member spaced apart. For this own dry fiber structures, such as fabric laminates and / or windings, wrapped or braided rovings or a combination thereof. An arrangement of the fiber structures can also by means of a Resin transfer molding process, by wet winding or with Help of so-called "prepregs" using an autoclave.

The spaced apart shell elements can by means of a plurality of connecting fibers are connected to each other. It is advantageous if the fiber structures of the shell elements Have force introduction areas for attachment of the connecting fibers, for example, loops.

One particularly reliable bond between the shell elements results when these by means of a plurality of connecting fibers sewn together. Here it is particularly favorable when the connecting fibers with the fiber structures of the shell elements sewn.

It is particularly preferred if an intermediate element between the fiber structures of the at least two shell elements is arranged. With such an intermediate element, a distance between two shell elements can be defined and the geometry of a cooling fluid space can be specified.

Preferably it is the intermediate element is a foam body. Such a body is dimensionally stable, allows but the simple passage of connecting fibers for connecting spaced-apart fiber structures.

A sees further advantageous embodiment of the invention that the intermediate element removed by heat input is, in particular, burned. This can be done in a simple way a cavity is created between two shell elements.

Further it is advantageous if, in the context of the production of the nozzle extension for producing a C / C material from a carbonaceous material Gas carbon is deposited on the fiber structures. This allows the preparation of a carbonaceous matrix, which surrounds the fiber structures. The deposition of carbon takes place in particular at a temperature level which is so high is that in the context of the deposition of carbon on the fiber structures also the intermediate element can be burned.

One Another advantageous method provides that for the production of a C / C material added to the fiber structures with a polymer and the polymer is pyrolyzed. this makes possible the preparation of a carbonaceous matrix containing the fiber structures surrounds.

A sees further advantageous embodiment of the invention in that at least one nozzle extension interior facing surface of a shell element is siliconized. In this way, the temperature and oxidation resistance of the nozzle shell in the thermally highest loaded Be increased portion of the nozzle shell.

To a further advantageous embodiment of the invention becomes the C / C material for the production of a C / C-SiC material infiltrated with silicon. This allows the production a high-strength matrix containing at least portions of silicon carbide contains.

Preferably is based on a cooling fluid space of the nozzle extension outside and / or inside arranged shell element with a provided gas-tight coating. This allows a simple sealing of the cold room to the outside and / or Inside. With a seal to the outside and inward can a pure convective cooling can be realized.

The The invention further relates to a method for cooling a Nozzle extension for an engine, in particular for a rocket engine, by means of a cooling fluid.

Of the The invention is based on the further object of a method for Cooling a nozzle extension for a Engine, which the use of a light, stable and thermally highly resilient nozzle extension allows.

These Task is in a method for cooling a nozzle extension for an engine according to the invention thereby solved that uses a turbine exhaust gas as the cooling fluid becomes.

Special Embodiments and advantages of the invention Method for cooling a nozzle extension for an engine are already partly related in the above with the particular features and advantages of the invention Nozzle extension has been explained, which hereby be referred to.

Especially it is preferred if for effusion or transpiration cooling the nozzle extension at least a partial flow of the turbine exhaust gas towards a nozzle extension interior at least one fluid-permeable shell element of a Nozzle jacket is passed. this makes possible a particularly efficient and even cooling of the nozzle jacket.

Further it is preferred if for convective cooling of the nozzle extension at least a partial flow of the turbine exhaust gas in the direction of a nozzle extension output is guided along at least one shell element along. This also allows efficient cooling of the nozzle extension.

The The invention further relates to the use of an initially explained Nozzle extension for carrying out an above described method for cooling a nozzle extension for an engine, especially for a rocket engine.

Further Features and advantages of the invention are the subject of the following Description and the drawings of preferred embodiments.

In show the drawings:

1 a perspective, partially sectioned view of an embodiment of a Dü senerweiterung;

2 a sectional side view of an embodiment of an engine with a nozzle extension according to 1 ;

3 a sectional side view of a section of an engine in the arrangement of a nozzle extension according to 1 at the exit of a combustion chamber using connection means;

4a an enlarged view of a connecting device according to a in 3 section marked IV;

4b a bottom view of a connecting element of the connecting device according to 4a ;

5 a front view of the connecting device according to an in 4a with VV designated cutting line;

6 a schematic representation of a mounting device for mounting a plurality of connecting devices according to 4a ;

7a -D perspective views of an embodiment of a nozzle shell of a nozzle extension according to 1 in the course of successive manufacturing steps;

8a a schematic view of an embodiment of an engine with a fuel delivery system and a nozzle extension according to 1 ;

8b a schematic view of another embodiment of an engine with a fuel delivery system and a nozzle extension according to 1 ;

9 a sectional side view of an embodiment of a nozzle extension with at least one multilayer shell element;

10 a sectional side view of an embodiment of a three-shell nozzle extension;

11 a sectional side view of another embodiment of a three-shell nozzle extension;

12 a sectional side view of another embodiment of a three-shell nozzle extension;

13 a perspective view of an embodiment of a shell member;

14 a perspective view of another embodiment of a shell member having a fluid barrier layer;

15a a sectional side view of an embodiment of a nozzle extension with a fluid-permeable support means;

15b a perspective view of the support device according to 15 ;

15c a schematic front view of the support device according to 15 ;

16a a plan view of an embodiment of a support means;

16b a plan view of another embodiment of a support means;

17 a plan view of another embodiment of a support means;

18 a sectional side view of an embodiment of a nozzle shell;

19 - 22 cut side views of other embodiments of a nozzle shell.

Same or functionally equivalent elements are in all figures denoted by the same reference numerals.

An embodiment of a with 10 designated nozzle extension is in the 1 to 3 shown. The nozzle extension 10 extends along an axis 12 between a nozzle extension input 14 and a nozzle extension output 16 ,

The nozzle extension 10 has a nozzle shell 18 on, which is circumferentially about the axis 12 extends and with an inner surface 20 a nozzle extension interior 22 limited.

From the nozzle extension input 14 towards the nozzle extension port 16 lie transverse to the axis 12 increasing flow cross sections 24 at.

The nozzle jacket 18 the nozzle extension 10 has two shell elements 26 . 28 on, which are made of a ceramic fiber composite material.

A first shell element 26 is based on a second shell element 28 arranged radially inward. The first shell element 26 limited to the inner surface 20 the nozzle extension inside room 22 ,

The second shell element 28 forms an outer shell of the nozzle shell 18 ,

The shell elements 26 and 28 are spaced apart in the radial direction and together define one between the shell elements 26 and 28 provided cooling fluid space 30 to flow through with a cooling fluid.

The cooling fluid space 30 is generally annular and extends between the nozzle extension input 14 and the nozzle extension output 16 ,

The shell elements 26 and 28 are shaped such that they are related to the axis 12 Distance measured in the radial direction 32 between the shell elements 26 and 28 starting from the nozzle extension input 14 to the nozzle extension output 16 reduced.

The nozzle extension 10 includes a support device 34 in the form of a support rib 36 which the shell elements 26 and 28 fixed together. The support rib 36 extends within a plane in which the axis 12 is arranged. A height applied in the radial direction 38 the support rib 36 corresponds to that along the axis 12 adjacent distance 32 between the shell elements 26 and 28 ,

The second shell element 28 indicates the nozzle extension input 14 an annular section 40 which is for connection to a combustion chamber device 42 serves (see 2 ).

The combustion chamber device 42 has a combustion chamber 44 on, which by means of an inner jacket 46 is limited. The combustion chamber device 42 further includes an outer sheath 48 , The outer jacket 48 forms an outer wall 50 the combustion chamber device 42 ,

The combustion chamber 44 extends in to the axis 12 the nozzle extension 10 parallel direction between an injection head 52 and a combustion chamber exit 54 ,

In the area of the combustion chamber outlet 54 or the nozzle extension input 14 are the flow cross sections of the inner shell 46 and the first shell element 26 identical.

The outer wall 50 and the second shell element 28 are in terms of their dimensions at the level of the combustion chamber exit 54 or the nozzle extension input 14 matched to one another such that they can be connected to one another by means of a connecting device described below.

The nozzle extension 10 includes a feeder 56 , by means of which a cooling fluid at the level of the nozzle extension input 14 or adjacent to the cooling fluid space 30 can be supplied.

The nozzle extension 10 further comprises a discharge device 58 by which the cooling fluid from the cooling fluid space 30 is deductible. The discharge device 58 is in the form of an annular gap 60 formed, which at the level of the nozzle extension output 16 is arranged.

The shell elements 26 and 28 are made of a porous, ceramic fiber composite material. The porosity of this material allows one in the cooling fluid space 30 arranged cooling fluid from the cooling fluid space 30 radially inward into the nozzle extension interior 22 can flow to the inner surface 20 to form a cooling film.

To exit the cooling fluid from the cooling fluid space 30 through the externally arranged shell element 28 to prevent through, includes the nozzle extension 10 a sealing device 62 in the form of a coating 64 , This is, for example, a metallic or ceramic additional layer, by means of which a fluid-tight, in particular gas-tight, barrier is formed.

The nozzle jacket 18 the nozzle extension 10 is effusion or transpiration cooled by at least a first partial flow 66 the cooling fluid from the cooling fluid space 30 through the first shell element 26 through into the nozzle extension interior 22 flows.

Additionally or alternatively, the nozzle shell 18 the nozzle extension 10 convectively cooled by at least a second partial flow 68 of the cooling fluid through the cooling fluid space 30 is passed through, thereby absorbs heat and at the annular gap 60 in an environment 65 the nozzle extension 10 exit.

At the in 2 illustrated embodiment corresponds to the direction of entry of the first partial flow 66 towards the nozzle extension interior 22 one related to the axis 12 radial direction. The first partial flow 66 However, it can also be found in a 2 With 70 indicated direction the nozzle extension interior 22 be fed, the direction 70 to the nozzle extension output 16 is oriented and with the inner surface 20 of the first shell element 26 includes an acute angle, which for example between 10 ° and 30 °. The direction 70 can be specified, for example, by the first shell element 26 provided with corresponding holes, which are made for example by lasers.

The nozzle extension 10 forms together with the combustion chamber device 42 an engine 74 in the form of a rocket engine.

The outer jacket 48 the combustion chamber device 42 has an annular, in 3 cut illustrated support section 76 on, the combustion chamber exit 54 limited. The support section 76 forms an axial stop for an annular edge portion 78 of the first shell element 26 ,

To connect the nozzle extension 10 with the combustion chamber device 42 is a connection device 80 intended. Preferably, by means of the connecting device 80 a biasing force generating the second shell element 28 the nozzle extension 10 and the outer wall 50 the combustion chamber device 42 pressed against each other, so that the edge portion 78 of the first shell element 26 under pretension on the support section 76 of the outer jacket 48 the combustion chamber device 42 is applied.

The connection device 80 comprises at least one connecting element 82 , which is designed in particular in the form of a "clip". The connecting element 82 is made of a metallic material, for example. The connecting element 82 includes a first connection portion 84 , which with the second shell element 28 interacts. The connecting element 82 further comprises a second connecting portion 86 , which with the outer wall 50 the combustion chamber device 42 interacts.

The connecting element 82 extends substantially in one to the axis 12 the nozzle extension 10 parallel direction.

The first connection section 84 and the second shell member 28 are in particular positively connected with each other. Such a positive connection can be made, for example, by a material section 88 in a complementary recess 90 dips. For example, it is the material section 88 around a fully cylindrical portion, which on the connecting element 82 is arranged and which in a cylindrical material recess 90 of the shell element 28 dips.

A positive connection between the outer wall 50 the combustion chamber device 50 and the connecting element 82 can also by means of a material section 92 and by means of a recess 94 getting produced. For example, the recess 94 on the outside wall 50 the combustion chamber device 42 arranged while the material section 92 on the connecting element 82 is arranged.

The material section 92 has a wedge surface 96 on, which with one through the recess 94 formed wedge surface 98 frictionally cooperates.

The connection device 80 includes at least one strap 100 . 102 , The tension bands 100 . 102 extend annularly around the annular portion 40 of the second shell element 28 or around the outer wall 50 the combustion chamber device 42 , The tension bands 100 . 102 prevent the fasteners 82 from the outside wall 50 or from the second shell element 28 peel off. The connecting elements 82 each produce a radially inwardly acting clamping force, which means with the wedge surfaces 96 and 98 in axial clamping forces 104 be redirected. By means of the clamping forces 104 become the second shell element 28 the nozzle extension 10 and the outer wall 50 the combustion chamber device 42 pressed against each other, so that the first shell element 26 with its edge section 78 under pretension on the support section 76 the combustion chamber device 42 is applied.

For sealing the second shell element relative to the outer wall 50 is at least one preferably foil-shaped seal 106 provided, which is formed in particular in the form of a graphite seal or copper seal.

To the clamping forces 104 in the circumferential direction relative to the axis 12 To be able to distribute evenly comprises the connecting device 80 preferably a plurality of connecting elements 82 which in particular at uniform angular intervals along the circumference of the second shell element 28 are distributed. For mounting the connecting elements 82 each two diametrically opposed clamping elements 82 by means of a tensioning device 108 braced (see 6 ). The tensioning device 108 includes a clamping element 110 whose distance to a counterholder 112 is adjustable, so that opposing clamping elements 82 for generating a clamping force 104 towards the nozzle extension interior 22 can be moved towards each other.

A particularly preferred manufacturing method for producing a nozzle shell 18 the nozzle extension 10 provides that a first Fa serstruktur 114 (please refer 7a ) is applied to a core whose geometry is the geometry of the nozzle extension interior 22 equivalent. The fiber structure 114 For example, it can be woven or stored on such a core, preferably automated.

Subsequently, an intermediate element 116 based on the fiber structure 114 be arranged radially outside. The intermediate element is preferably a foam body. The geometry of the intermediate element corresponds to the geometry of the cooling fluid space 30 the nozzle extension 10 ,

Subsequently, a second fiber structure 118 based on the intermediate element 116 arranged radially on the outside. In this way are the fiber structures 114 and 118 spaced apart, wherein between these fiber structures, the intermediate element 116 is arranged.

The fiber structures 114 and 118 subsequently with the help of connecting fibers 120 connected together, in particular sewn together. The connecting fibers 120 are especially carbon fibers. The connecting fibers 120 extend with respect to the axis 12 the nozzle extension 10 in the radial direction. The connecting fibers 120 are each one end with the first fiber structure 114 and with the other end with the second fiber structure 118 sutured. The connecting fibers 120 run through the intermediate element 116 therethrough.

In a subsequent step, a matrix material is produced which contains the fiber structures 114 and 118 surrounds. To produce the matrix material, a carbon from a carbon-containing gas can be applied to the fiber structures 114 and 118 be deposited. This deposition takes place in an environment which has a temperature which is so high that the intermediate element 116 is burned. The deposition of the carbon produces an integral component of C / C material, which forms the fiber structures 114 and 118 and a matrix material of carbon. The C / C material can also be made by adding the fiber structures 114 and 118 with a polymer (for example as part of a resin transfer molding process) and the polymer is pyrolyzed to produce a carbonaceous matrix material.

To increase the temperature resistance, in particular of the first shell element 26 In a subsequent manufacturing step, at least the inner surface 20 of the first shell element 26 which the first fiber structure 114 contains, silicates. In this case, silicon is supplied to the C / C material (for example by means of liquid phase infiltration into the porous C / C material) which reacts with at least a proportion of the matrix carbon to form silicon carbide. In this way, an oxidation-resistant and highly temperature-resistant inner surface 20 be created. It may also be a complete silicification of at least one shell element 26 . 28 be provided.

In a further production step, the second shell element 28 with a gas-tight coating 64 be provided. The coating 64 can on the the cooling fluid space 30 opposite side and / or on the cooling fluid space 30 facing side of the second shell element 28 be applied.

Following the above with reference to the 7a to 7d described production of the nozzle shell 18 can the annular section 40 ( 1 ) with the nozzle jacket 18 get connected. The annular section 40 can be made of a metallic or ceramic material and positive and / or material fit with the nozzle shell 18 get connected.

In 8a is an embodiment of an engine 74 shown, which is a nozzle extension 10 , a combustion chamber device 42 and a fuel delivery system 122 includes.

The fuel delivery system 122 has a first container 124 for storing a fuel 126 on. For example, the fuel is liquid hydrogen.

The fuel delivery system 122 includes a second container 128 for storing an oxidizer 130 , These are in particular liquid oxygen.

The fuel delivery system 122 further includes a first pump 132 , which by means of a first turbine 134 is driven. Furthermore, the fuel delivery system includes 122 a second pump 136 , which by means of a second turbine 138 is driven.

The fuel delivery system also includes a gas generator 140 ,

To promote the fuel 126 and the oxidizer 130 to the injection head 52 the combustion chamber device 42 become high drive power for the pumps 132 and 136 needed. To generate this drive power is a subset of the fuel 126 and the oxidizer 130 the gas generator 140 fed to a gas to drive the turbines 134 and 138 to create. In this way, the pumps can 132 and 136 driven who the, to the injection head 52 fuel 126 and oxidizer 130 supply. In addition, a subset of the fuel 126 for cooling the combustion chamber device 42 be used.

This in 8a shown engine 74 can be operated in a bypass cycle. Here is a the turbines 134 and 138 outgoing turbine exhaust not the injection head 52 supplied but the cooling fluid space 30 the nozzle extension 10 , This cooling fluid has a temperature of for example 650 Kelvin at a turbine outlet pressure of for example about 4 bar. The turbine exhaust is by means of the feeder 56 the cooling fluid space 30 supplied, flows through this and occurs at the annular gap 60 at the height of the nozzle extension output 16 in the nearby areas 65 from and / or passes through the first shell element 26 through into the nozzle extension interior 22 ,

This in 8a shown engine 74 can also be operated in a main flow cycle. This mode will be described below with reference to a in the 8b illustrated embodiment of an engine 74 with a fuel delivery system 122 explains its gas generator 140 is formed in the form of a pre-combustion chamber. When operating an engine 74 in the main flow cycle becomes the fuel 126 and the oxidizer 130 exclusively via the injection head 52 the combustion chamber 44 fed. In this case, at least a partial flow of the turbine exhaust gas of the turbines 134 and 138 the injection head 52 fed. For cooling the nozzle extension 10 becomes part of the turbine exhaust gas of the turbines 134 and 138 branched off and by means of the feeder 56 the cooling fluid space 30 the nozzle extension 10 fed.

Alternatively or in addition to the possibility described above, the nozzle extension 10 an engine 74 to cool by means of a turbine exhaust gas, the nozzle extension 10 also be cooled by the fuel 126 by means of a connecting line between the pump, not shown in the drawing 132 and the feeder 56 the cooling fluid space 30 is supplied.

The following are with reference to the 9 to 12 alternative embodiments of the nozzle shell 18 a nozzle extension 10 described.

The nozzle jacket 18 For example, at least one shell element 26 . 28 include, which is multi-layered and thus forms a sandwich component. For example, the first shell element 26 be designed as a sandwich component (see 9 , upper half). As a result, a particularly good cooling effect is achieved.

Alternatively, only the second shell element may be designed as a sandwich component or it may be the first shell element 26 and the second shell member 28 be designed as a sandwich component (see 9 , bottom half). The use of a sandwich component has the advantage that a particularly stable, multi-layered shell element 26 . 28 can be created.

The in the 10 to 12 illustrated embodiments of a nozzle extension 10 comprising a nozzle shell 18 which in addition to the first shell element 26 and the second shell member 28 at least a third shell element 142 include. Under a third shell element 142 is understood a shell element, which is at least partially between the nozzle extension input 14 and the nozzle extension output 16 extends and referred to an axis 12 in the radial direction between the first shell element 26 and the second shell member 28 is arranged.

For example, the third shell element extends 142 in full length between the nozzle extension input 14 and the nozzle extension output 16 ( 10 ). The third shell element 142 is preferably to at least one shell element 26 . 28 spaced, in particular to both shell elements 26 . 28 , In a spaced arrangement of the third shell element 142 to the first shell element 26 creates a free space, which as a cooling fluid space 30 can be used to flow through with a cooling fluid. Alternatively or in addition to this, a between the second shell element 28 and the third shell element 142 trained space 144 be used for flow with a cooling fluid.

At an in 11 illustrated embodiment of a nozzle extension 10 is a third shell element 142 provided, which only partially between a nozzle extension input 14 and a nozzle extension output 16 extends. In this way, one to the nozzle extension input 14 adjacent section of the nozzle shell 18 be stiffened. The third shell element 142 Can with its the nozzle extension output 16 facing end with the second shell element 28 get connected ( 11 , upper half) or with the first shell element 26 ( 11 , bottom half).

For producing a particularly stiff nozzle shell 18 It is possible to have at least three shell elements 26 . 28 . 142 to use, spaced them to arrange and the spaces with a filler 146 to fill ( 12 . upper half).

When using the cooling fluid space 30 and / or the gap 144 to flow through with a cooling fluid, it is advantageous, the shell elements 26 . 28 and or 142 at her the nozzle extension input 14 facing end opposite the annular portion 40 with the help of annular seals 148 relative to the annular portion 40 seal. Furthermore, it is for sealing the cooling fluid space 30 advantageous that third shell element 142 at least partially with a gas-tight coating 64 to provide.

An in 13 illustrated embodiment of a first shell element 26 has a variety of recesses 150a . 150b . 150c on. The recesses 150a to 150c are above the first shell element 26 arranged distributed.

The recesses 150a to 150c allow passage of cooling fluid through the shell member 26 through into the nozzle extension interior 22 ,

The recesses 150a to 150c are distributed in such a way and in terms of their size coordinated so that one in the direction of the nozzle extension interior 22 pointing cooling fluid flow in one to the nozzle extension input 14 adjacent area is higher than in one to the nozzle extension output 16 adjacent area. This allows the shell element 26 in the area of the nozzle extension input 14 or to be cooled more closely adjacent thereto than in the region of the nozzle extension output 16 or adjacent thereto.

For a locally different cooling of a shell element may also be in 14 illustrated fluid barrier layer 152 be used. Such a barrier layer prevents, at least in sections, the passage of a cooling fluid through a shell element, for example through a first shell element 26 , through.

The fluid barrier layer 152 has a plurality of fluid passage openings 154a . 154b . 154c on. These fluid passage openings are over the first shell element 26 arranged distributed and allow passage of a cooling fluid in the direction of the shell element 26 , which is preferably porous, so that the cooling fluid through the shell element 26 through the nozzle extension interior 22 can be fed.

The fluid barrier layer 152 For example, it can be applied as a coating to an outside or inside of a shell element. For this example, a cold gas sputtering can be used.

Another way to control a fluid passage along the extension of a shell member is to make the shell member from a material whose porosity is from a nozzle extension entrance 14 towards a nozzle extension output 16 changed, preferably reduced.

An in 15a illustrated embodiment of a nozzle extension 10 has a first shell element 26 , a second shell element 28 and one through the shell elements 26 and 28 limited refrigerator 30 on.

The nozzle extension 10 according to 15a further comprises a support means 34 which the shell elements 26 and 28 spaced apart and fixed relative to each other.

The support device 34 For example, it extends spirally or circumferentially relative to the axis 12 the nozzle extension 10 , Preferably, in to the axis 12 seen parallel direction seen several successively arranged support means 34 intended.

The support device 34 is inside the cooling fluid space 30 arranged, in such a way that it can be flowed through by a cooling fluid.

The support device 34 has an input side support element section 156 and an output side support member portion 158 on. The support element sections 156 and 158 are by means of a connection section 160 connected with each other.

The support element sections 156 and 158 are fluid-permeable, for example by a corresponding perforation or by a porous formation of a support element section.

The support element sections 156 and 158 are matched with respect to their fluid permeability to one another such that a cooling fluid flow 162 after passing through the input side support element section 156 is attenuated, so that a cooling fluid flow 164 upstream of the output side support member portion 158 smaller than the cooling fluid flow 162 , In this way, the cooling of the nozzle extension 10 starting from a nozzle extension input 14 towards a nozzle extension output 16 be varied.

One in the 16a illustrated embodiment of a support device 34 is in the form of a support rib 36 formed, which for use in a nozzle extension 10 is provided. The supporting rib 36 has two lateral support element sections 166 and 168 on. These each adjoin a cooling fluid space 30a . 30b ,

The support element sections 166 and 168 indicate a nozzle extension input 14 going to a nozzle extension output 16 a mutually variable distance. Preferably, the distance between the support element sections increases 166 and 168 so that one through the cooling fluid spaces 30a . 30b passed cooling fluid is accelerated and thus the cooling fluid pressure from the nozzle extension input 14 towards the nozzle extension output 16 decreases. This leads to the arrangement of the support device 34 on a porous shell element 26 to have one in a nozzle extension interior 22 directed cooling fluid flow from the nozzle extension inlet 14 towards the nozzle extension output 16 decreases.

The support element sections 166 and 168 can relate to an axis 12 symmetrical course or be asymmetric ( 16b ).

An in 17 illustrated embodiment of a support device 34 has two support ribs 36 which is located between a nozzle extension input 14 and a nozzle extension output 16 extend. A distance 170 between the support ribs 36 increases along the axis 12 seen from the nozzle extension input 14 towards the nozzle extension output 16 , As a result, the cross sections of the support ribs 36 adjacent cooling fluid spaces 30a . 30b reduced.

An in 18 illustrated embodiment of a nozzle shell 18 comprises a fluid-permeable first shell element 26 and a second shell element arranged radially outwards for this purpose 28 ,

The second shell element 28 is multi-part and comprises a plurality of respective annular shell element sections 172a . 172b , The shell element sections 172a . 172b are in one direction from a nozzle extension input 14 towards a nozzle extension output 16 seen consecutively arranged.

The shell element sections 172a . 172b have fluid-permeable wall sections 174a . 174b which is transverse to a cooling fluid flow 162 . 164 extend. The wall sections 174a . 174b are preferably matched to one another such that a cooling fluid flow 162 . 164 is attenuated in the flow direction of a cooling fluid to a first shell element 26 in one to a nozzle extension input 14 To be able to cool more strongly adjacent area than in a nozzle extension to a nozzle extension 16 adjacent area.

In the 18 illustrated embodiment of a nozzle shell 18 can also be referred to as a "shingle construction".

The in the 19 and 20 illustrated embodiments of a nozzle shell 18 each have a one-piece shell element 26 and a one-piece shell member 28 on. The shell elements 26 and 28 are spaced apart so that a cooling fluid space 30 arises. In the cooling fluid space 30 are transverse to a cooling fluid flow 162 . 164 extending wall sections 174a . 174b arranged, which are fluid-permeable.

At the in 19 illustrated embodiment of a nozzle shell 18 go the fluid-permeable wall sections 174a . 174b in peripheral wall sections 176a . 176b over which on the second shell element 28 issue.

The in the 20 illustrated embodiment of a nozzle shell 18 additionally has peripheral wall sections 178a . 178b on which on the first shell element 26 abutment and for a passage of a cooling fluid flow toward a nozzle extension interior 22 are fluid-permeable.

At an in 21 illustrated embodiment of a nozzle shell 18 is the second shell element 28 with the help of the adjoining peripheral wall sections 176a . 176b educated.

At an in 22 illustrated embodiment is also the first shell element beyond 26 with the help of successive wall sections 178a . 178b educated.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - US 6467253 B1 [0002]

Claims (61)

Nozzle extension ( 10 ) for an engine ( 74 ), with a nozzle shell ( 18 ), which has a flow cross-section ( 24 ), which extends from a nozzle extension input ( 14 ) to a nozzle extension output ( 16 ), whereby the nozzle extension input ( 14 ) with a combustion chamber outlet ( 54 ) a combustion chamber ( 44 ) of an engine ( 74 ) is connectable, characterized in that the nozzle casing ( 18 ) at least two made of a ceramic fiber composite material, relatively fixed shell elements ( 26 . 28 . 142 ) having. Nozzle extension ( 10 ) according to claim 1, characterized by a first shell element ( 26 ), which has a nozzle extension interior ( 22 ) limited. Nozzle extension ( 10 ) according to claim 2, characterized in that at least a portion of the first shell element ( 26 ) is fluid-permeable. Nozzle extension ( 10 ) according to claim 2 or 3, characterized in that at least a portion of the first shell element ( 26 ) is porous. Nozzle extension ( 10 ) according to one of the preceding claims, characterized by a second shell element ( 28 ), which the nozzle extension ( 10 ) is limited to the outside. Nozzle extension ( 10 ) according to one of the preceding claims, characterized by at least one third shell element ( 142 ), which between a first shell element ( 26 ) and a second shell element ( 28 ) is arranged. Nozzle extension ( 10 ) according to claim 6, characterized in that at least a portion of the third shell element ( 142 ) is fluid-permeable. Nozzle extension ( 10 ) according to claim 6 or 7, characterized in that at least a portion of the third shell element ( 142 ) is porous. Nozzle extension ( 10 ) according to one of claims 6 to 8, characterized in that the third shell element ( 142 ) at least two shell element sections ( 172a . 172b ), which in one direction from the nozzle extension input ( 14 ) on the nozzle extension output ( 16 ) are arranged following each other. Nozzle extension ( 10 ) according to claim 9, characterized in that successive shell element sections ( 172a . 172b ) have different properties with regard to their fluid permeability and / or porosity. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that at least one shell element ( 26 . 28 . 142 ) at least in sections with a fluid barrier layer ( 152 ) is provided. Nozzle extension ( 10 ) according to claim 11, characterized in that the fluid barrier layer ( 152 ) at least one fluid passage opening ( 154a . 154b . 154c ) having. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that the fiber composite material is a C / C material. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that the fiber composite material is silicided. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that the fiber composite material is a C / SiC material. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that the fiber composite material is a C / C-SiC material. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that at least one of the shell elements ( 26 . 28 . 142 ) is integral. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that at least one of the shell elements ( 26 . 28 . 142 ) is single-layered. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that at least one of the shell elements ( 26 . 28 . 142 ) is multilayered. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that at least two shell elements ( 26 . 28 . 142 ) are integral with each other. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that at least two shell elements ( 26 . 28 . 142 ) are spaced from each other. Nozzle extension ( 10 ) according to claim 21, characterized in that the distance between the at least two shell elements ( 26 . 28 . 142 ) out going from the nozzle extension input ( 14 ) towards the nozzle extension port ( 16 ) reduced. Nozzle extension ( 10 ) according to one of the preceding claims, characterized by at least one support device ( 34 ), by means of which at least two shell elements ( 26 . 28 . 142 ) are fixable relative to each other and / or spaced. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that at least two shell elements ( 26 . 28 . 142 ) by means of connecting fibers ( 120 ) are interconnected. Nozzle extension ( 10 ) according to one of the preceding claims, characterized in that at least two shell elements ( 26 . 28 . 142 ) by means of connecting fibers ( 120 ) are sewn together. Nozzle extension ( 10 ) according to claim 19 or 20, characterized in that at least a part of the connecting fibers ( 120 ) Are carbon fibers. Nozzle extension ( 10 ) according to one of the preceding claims, characterized by at least one cooling fluid space ( 30 ) to flow through with a cooling fluid. Nozzle extension ( 10 ) according to claim 21, characterized in that the cooling fluid space ( 30 ) between at least two shell elements ( 26 . 28 . 142 ) is arranged. Nozzle extension ( 10 ) according to claim 27 or 28, characterized by a feed device ( 56 ) for the supply of the cooling fluid into the cooling fluid space ( 30 ). Nozzle extension ( 10 ) according to claim 29, characterized in that the feeding device ( 56 ) at or adjacent to the nozzle extension input (FIG. 14 ) is arranged. Nozzle extension ( 10 ) according to one of claims 27 to 30, characterized by a discharge device ( 58 ) for the removal of the cooling fluid from the cooling fluid space ( 30 ). Nozzle extension ( 10 ) according to claim 31, characterized in that the discharge device ( 58 ) at or adjacent to the nozzle extension port ( 16 ) is arranged. Nozzle extension ( 10 ) according to one of claims 27 to 32, characterized by at least one sealing device ( 62 ) for sealing the cooling fluid space ( 30 ) outward. Nozzle extension ( 10 ) according to claim 33, characterized in that at least one shell element ( 26 . 28 . 142 ) as a sealing device ( 62 ) is effective. Nozzle extension ( 10 ) according to claim 33 or 34, characterized in that at least one sealing device ( 62 ) of a shell element ( 26 . 28 . 142 ) is provided separately. Nozzle extension ( 10 ) according to one of claims 33 to 35, characterized in that the at least one sealing device ( 62 ) is provided in the form of a gaseous barrier layer. Nozzle extension ( 10 ) according to any one of claims 27 to 36, characterized in that the cooling fluid is a fuel. Nozzle extension ( 10 ) according to one of claims 27 to 37, characterized in that the cooling fluid is a turbine exhaust gas. Nozzle extension ( 10 ) according to claim 38, characterized in that the turbine exhaust gas of a fuel delivery system ( 122 ) is taken. Nozzle extension ( 10 ) according to one of the preceding claims, characterized by at least one connecting device ( 80 ) for connecting the nozzle extension ( 10 ) with a combustion chamber device ( 42 ). Nozzle extension ( 10 ) according to claim 40, characterized in that the connecting device ( 80 ) a first connection section ( 84 ), which is provided with at least one shell element ( 26 . 28 . 142 ) cooperates. Nozzle extension ( 10 ) according to claim 41, characterized in that the shell element ( 28 ) the nozzle extension ( 10 ) is limited to the outside. Nozzle extension ( 10 ) according to one of claims 40 to 42, characterized in that the combustion chamber device has an outer wall ( 50 ) and that the connection device ( 80 ) a second connecting section ( 86 ), which with the outer wall ( 50 ) cooperates. Method for producing a nozzle extension ( 10 ) for an engine ( 74 ), characterized in that at least two shell elements ( 26 . 28 . 142 ) of a nozzle shell ( 18 ) are made of a ceramic fiber composite material. Method according to claim 44, characterized in that a first fiber structure ( 114 ) for a first shell element ( 26 ) and a second fiber structure ( 118 ) for a second shell element ( 28 ) are arranged spaced from each other. Method according to claim 44 or 45, characterized in that the at least two shell elements ( 26 . 28 . 142 ) by means of a plurality of connecting fibers ( 120 ). Method according to one of claims 44 to 46, characterized in that the at least two shell elements ( 26 . 28 . 142 ) by means of a plurality of connecting fibers ( 120 ) are sewn together. Method according to one of claims 45 to 47, characterized in that an intermediate element ( 116 ) between the fiber structures ( 114 . 118 ) of the at least two shell elements ( 26 . 28 . 142 ) is arranged. Method according to claim 48, characterized in that the intermediate element ( 116 ) is a foam body. Method according to claim 48 or 49, characterized in that the intermediate element ( 116 ) is removed by heat input. Method according to one of claims 45 to 50, characterized in that for the production of a C / C material from a carbon-containing gas carbon on the fiber structures ( 114 . 118 ) is deposited. Method according to one of claims 45 to 51, characterized in that for the production of a C / C material, the fiber structures ( 114 . 118 ) are added with a polymer and the polymer is pyrolyzed. Method according to one of claims 37 to 45, characterized in that at least one nozzle extension interior ( 22 ) facing surface ( 20 ) of a shell element ( 26 ) is silicified. Method according to one of claims 51 to 53, characterized in that the C / C material for producing a C / C-SiC material is infiltrated with silicon. Method according to one of claims 44 to 54, characterized in that at least one with respect to a cooling fluid space ( 30 ) of the nozzle extension ( 10 ) outer shell element ( 28 . 142 ) with a gas-tight coating ( 64 ). Method according to one of claims 44 to 55, characterized in that at least one with respect to a cooling fluid space ( 30 ) of the nozzle extension ( 10 ) internally arranged shell element ( 26 ) with a gas-tight coating ( 64 ). Method for cooling a nozzle extension ( 10 ) for an engine ( 74 ) by means of a cooling fluid, characterized in that a turbine exhaust gas is used as cooling fluid. A method according to claim 57, characterized in that the turbine exhaust gas of a fuel delivery system ( 122 ) is taken. A method according to claim 57 or 58, characterized in that for the effusion or transpiration cooling of the nozzle extension ( 10 ) at least one substream ( 66 ) of the turbine exhaust gas towards a nozzle extension interior ( 22 ) by at least one fluid-permeable shell element ( 26 ) of a nozzle shell ( 18 ) is passed through. Method according to one of claims 57 to 59, characterized in that for the convective cooling of the nozzle extension ( 10 ) at least one substream ( 68 ) of the turbine exhaust gas towards a nozzle extension port ( 16 ) on at least one shell element ( 26 . 28 . 142 ) is guided along. Using a nozzle extension ( 10 ) according to one of claims 1 to 43 for carrying out a method according to one of claims 57 to 60.