WO2021242229A1

WO2021242229A1 - Two-piece combustor

Info

Publication number: WO2021242229A1
Application number: PCT/US2020/034672
Authority: WO
Inventors: Peter Kinsman; Jr. Calvin Q. Morrison; Luis A. Rosales
Original assignee: Aerojet Rocketdyne, Inc.
Priority date: 2020-05-27
Filing date: 2020-05-27
Publication date: 2021-12-02

Abstract

A combustor includes a pressure-containing housing (22) and a one- piece body (24) disposed along an axis. The one-piece body has an exhaust manifold section (40) and a liner section (42). The exhaust manifold section defines a flow path and the liner section at least partially defines a combustion chamber (26) and extends axially from the exhaust manifold section into the pressure-containing housing. The exhaust manifold section is hermetically sealed to the housing. The liner section loosely abuts the pressure-containing housing at an end opposite the exhaust manifold section. The liner section and pressure-containing housing define an insulation cavity (58).

Description

TWO-PIECE COMBUSTOR

BACKGROUND

[0001] High performance combustors for advanced engines, such as axial combustors in engines for aquatic vehicles, include numerous components. The components are highly specialized. In order to meet performance goals, manufacturing requirements, and/or material requirements, the components are separately fabricated and then assembled together to form the end-use combustor.

SUMMARY

[0002] A combustor according to an example of the present disclosure includes a pressure-containing housing disposed along an axis, and a one-piece body also disposed along the axis. The one-piece body has an exhaust manifold section and a liner section. The exhaust manifold section defines a flow path and the liner section at least partially defining a combustion chamber and extending axially from the exhaust manifold section into the pressure- containing housing. The exhaust manifold section is hermetically sealed to the housing. The liner section loosely abuts the pressure-containing housing at an end opposite the exhaust manifold section. The liner section and pressure-containing housing define an insulation cavity.

[0003] In a further embodiment of any of the foregoing embodiments, the liner section includes orifices fluidly coupling the insulation cavity and the combustion chamber.

[0004] In a further embodiment of any of the foregoing embodiments, the one-piece body is molybdenum alloy.

[0005] In a further embodiment of any of the foregoing embodiments, the one-piece body is ceramic.

[0006] In a further embodiment of any of the foregoing embodiments, the pressure- containing housing is a metallic material that is selected from the group consisting of titanium alloy and nickel-chromium-tungsten-molybdenum alloy, and the one-piece body is molybdenum alloy.

[0007] In a further embodiment of any of the foregoing embodiments, the pressure- containing housing and the one-piece body are in contact exclusively at first and second joints located, respectively, at a base of the liner at the exhaust manifold section and the end opposite the exhaust manifold section. [0008] In a further embodiment of any of the foregoing embodiments, the pressure- containing housing includes an annular mate face in contact with the liner section in the first joint.

[0009] In a further embodiment of any of the foregoing embodiments, the pressure- containing housing includes an expansion gap next to the annular mate face for accommodating thermal expansion of the liner section.

[0010] In a further embodiment of any of the foregoing embodiments, the pressure- containing housing includes an annular channel located axially intermediate the first and second joints.

[0011] A combustor according to an example of the present disclosure includes a one-piece body disposed along an axis and formed of a refractory material. The one-piece body has an exhaust manifold section and a liner section. The exhaust manifold section defines exhaust channels and the liner section circumscribes a combustion chamber and extends axially from the exhaust manifold section.

[0012] In a further embodiment of any of the foregoing embodiments, the refractory material is molybdenum alloy.

[0013] In a further embodiment of any of the foregoing embodiments, the refractory material is ceramic.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The various features and advantages of the present disclosure will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows.

[0015] Figure 1 illustrates an example combustor.

[0016] Figure 2 illustrates another example combustor.

DETAILED DESCRIPTION

[0017] Figure 1 schematically illustrates a combustor 20. For example, the combustor 20 may find use in advanced engines for aquatic vehicles, but is not limited thereto. As will be described, the combustor 20 is of two-piece can architecture.

[0018] The two-piece architecture of the combustor 20 includes a pressure- containing housing 22 and a one-piece body 24 disposed along an axis A. The pressure- containing housing 22 and the one-piece body 24 are engaged together to form a combustion chamber 26 in which hot gases are generated. In this regard, the pressure-containing housing 22 and the one-piece body 24 are formed from materials that are able to withstand the exposure temperatures. For instance, the pressure-containing housing 22 is formed from a ceramic material, a metallic alloy, such as Inconel-718 or Haynes-230, a titanium alloy, or other high temperature alloy. Such alloys provide good temperature resistance, as well as high strength- to-weight ratio. The one-piece body 24 is generally exposed to higher temperatures than the pressure-containing housing 22 and is thus formed of a refractory material, such as a ceramic material, molybdenum alloy, niobium alloy, tungsten alloy, although the molybdenum alloy provides a useful balance of properties.

[0019] The one-piece body 24 is of unitary construction, as opposed to a group of mechanically attached components that make up an assembly. For instance, all portions of the one-piece body 24 are fused together as one piece. In further examples, the one-piece body 24 is a monolithic body of the refractory material. The monolithic body is a single, continuous piece, as opposed to a collection of functional parts that are bonded, secured, fused together, or mechanically attached in joints. For example, a monolithic body may be formed by casting, additive manufacturing from a starting powder, machining, or forging or other wrought processing.

[0020] As shown, the pressure-containing housing 22 in this example is comprised of a neck 28, which serves for injection of propellant into the combustion chamber 26, a bulkhead wall 30, and an annular wall 32. The neck 28 may be varied or even excluded, depending on the particular design of the combustor 20. The bulkhead wall 30 extends radially from the neck 28, and the annular wall 32 extends axially from the bulkhead wall 30. On its inside diameter surface the annular wall 32 includes a first annular mate face 32a and a second annular mate face 32b, which as described below interface with the one-piece body 24. In this example, there is also an annular channel 34 axially intermediate of the first and second annular mate faces 32a/32b.

[0021] In the illustrated example, the one-piece body 24 includes an exhaust manifold section 40 and a liner section 42. In this example, the exhaust manifold section 40 defines one or more axial exhaust ports 44 (flow passages). Figure 2 shows the combustor 20 in a varied design in which, rather than the axial exhaust port 44, there is at least one radial exhaust port 144. It is to be further understand that additional variations may include both axial and radial exhaust ports. The axial or radial exhaust ports 44/144 are fluidly connected to the combustion chamber 26 and serve to discharge hot gases from the combustion chamber 26. In this example, the exhaust manifold section 40 also includes a torque transmission feature 46, for attachment with a rotatable shaft (not shown). In this regard, the combustor 20 is rotatable and thus co-rotates with the shaft during operation.

[0022] The liner section 42 includes an annular liner wall 48 that extends axially from the exhaust manifold section 40 and circumscribes the combustion chamber 26. The annular liner wall 48 extends into the pressure-containing housing 22 and generally serves to shield the annular wall 32 from the hot gases in the combustion chamber 26.

[0023] In this example, the pressure-containing housing 22 and the one-piece body 24 are in contact exclusively at first and second joints 50/52 that are located, respectively, at the base of the annular liner wall 48 (at the exhaust manifold section 40) and an opposed end of the annular liner wall 48 (the free end). In each of the locations, the annular liner wall 48 contacts the respective annular mate faces 32a/32b of the annular wall 32. The annular mate faces 32a/32b may serve for mechanical support and piloting to facilitate proper positioning of the annular liner wall 48 with respect to the annular can wall 32. Seals may be provided in or near the annular mate face 32b to hermetically seal the exhaust manifold section 40 and the pressure-containing housing 22 together.

[0024] A backstop face 54 serves to limit the extent that the annular liner wall 48 projects into the pressure-containing housing 22. The pressure-containing housing 22, however, does not include a similar backstop but rather an expansion gap 56 axially adjacent the first mate face 32a. The expansion gap 56 permits axial thermal expansion of the annular liner wall 48 to thereby facilitate avoidance of thermal stresses between the can 22 and the one- piece body 24.

[0025] In the illustrated example, the annular liner wall 48 encloses an insulation space 58 between its outer diameter surface and the annular channel 34 of the annular wall 32. The insulation space 58 may be cooled through the annular wall 32 in order to facilitate thermal management of the annular liner wall 48. Orifices 60 are provided through the annular liner wall 48 to connect the insulation space 58 with the combustion chamber 26. The orifices 60 are relatively small so as to permit pressure equalization of the insulation space 58 with the combustion chamber 26 but otherwise limit ingress flow of hot gases into the insulation space 58. The high pressure combustion gases that are generated in the combustion chamber 26 expand and immediately fill the insulation space 58 through the orifices 60. This produces a pressure equalization volume as well as a volume of insulating gas between the cool (outer) annular wall 32 and the hot (inner) annular liner wall 48. The net volume of remaining gas exits the combustion chamber 26 via the axial and/or radial exhaust ports 44/144 and is distributed as high-temperature , high-pressure gas applying direct force in a mechanical system, to create work, downstream of the combustion process.

[0026] As indicated above, the annular liner wall 48 and the exhaust manifold section 40 are of unitary construction. The unitary construction serves to eliminate seals and additional parts, thereby making the combustor 20 more compact. For instance, in multi-piece constructions a manifold piece may be attached by a sealed threaded fastener connection to a liner sleeve. However, with the unitary construction, the threaded connection and sealing of that connection are unnecessary, which may also facilitate reductions in leak paths and fabrication steps.

[0027] Although a combination of features is shown in the illustrated examples, not all of them need to be combined to realize the benefits of various embodiments of this disclosure. In other words, a system designed according to an embodiment of this disclosure will not necessarily include all of the features shown in any one of the Figures or all of the portions schematically shown in the Figures. Moreover, selected features of one example embodiment may be combined with selected features of other example embodiments.

[0028] The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from this disclosure. The scope of legal protection given to this disclosure can only be determined by studying the following claims.

Claims

CLAIMS What is claimed is:

1. A combustor comprising: a pressure-containing housing disposed along an axis; and a one-piece body also disposed along the axis, the one-piece body having an exhaust manifold section and a liner section, the exhaust manifold section defining a flow path and the liner section at least partially defining a combustion chamber and extending axially from the exhaust manifold section into the pressure-containing housing, wherein the exhaust manifold section is hermetically sealed to the housing, and wherein the liner section loosely abuts the pressure-containing housing at an end opposite the exhaust manifold section, and the liner section and pressure-containing housing define an insulation cavity.

2. The combustor of claim 1, wherein the liner section includes orifices fluidly coupling the insulation cavity and the combustion chamber.

3. The combustor as recited in claim 1, wherein the one-piece body is molybdenum alloy.

4. The combustor as recited in claim 1, wherein the one-piece body is ceramic.

5. The combustor as recited in claim 1, wherein the pressure-containing housing is a metallic material that is selected from the group consisting of titanium alloy and nickel- chromium-tungsten-molybdenum alloy, and the one-piece body is molybdenum alloy.

6. The combustor as recited in claim 1, wherein the pressure-containing housing and the one-piece body are in contact exclusively at first and second joints located, respectively, at a base of the liner at the exhaust manifold section and the end opposite the exhaust manifold section.

7. The combustor as recited in claim 6, wherein the pressure-containing housing includes an annular mate face in contact with the liner section in the first joint.

8. The combustor as recited in claim 7, wherein the pressure-containing housing includes an expansion gap next to the annular mate face for accommodating thermal expansion of the liner section.

9. The combustor as recited in claim 7, wherein the pressure-containing housing includes an annular channel located axially intermediate the first and second joints.

10. A combustor comprising: a one-piece body disposed along an axis and formed of a refractory material, the one- piece body having an exhaust manifold section and a liner section, the exhaust manifold section defining exhaust channels and the liner section circumscribing a combustion chamber and extending axially from the exhaust manifold section.

11. The combustor as recited in claim 10, wherein the refractory material is molybdenum alloy.

12. The combustor as recited in claim 10, wherein the refractory material is ceramic.