WO2013187936A1

WO2013187936A1 - Additive manufacturing flow control

Info

Publication number: WO2013187936A1
Application number: PCT/US2013/020313
Authority: WO
Inventors: Brian Boyce
Original assignee: Pratt & Whitney Rocketdyne, Inc.
Priority date: 2012-06-15
Filing date: 2013-01-04
Publication date: 2013-12-19

Abstract

An apparatus includes an additive manufacture housing that at least partially defines a cavity and a passage in fluid communication therewith and an additive manufacturing non-integral part movably disposed within said cavity, the non-integral part defines a geometry that cannot fit through said passage.

Description

ADDITIVE MANUFACTURING FLOW CONTROL

REFERENCE TO RELATED APPLICATIONS

[0001] The present disclosure claims priority to United States Provisional Patent Disclosure Serial No. 61/660,562, filed June 15, 2012, which is incorporated by reference herein.

BACKGROUND

[0001] The present disclosure relates to additive manufacturing techniques, and more particularly to a flow control manufactured thereby.

[0002] Rocket engines deliver fuel and oxidizer to a combustion chamber through an injector assembly where the propellants are atomized, mixed, and combusted. Certain rocket engines adjust the quantity of propellant injected into the combustion chamber yet maintain propellant pressures across the injector assembly.

[0003] The injector assembly has a relatively large internal volume and may potentially generate combustion instabilities and back flow under transient operations.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Various features will become apparent to those skilled in the art from the following detailed description of the disclosed non-limiting embodiment. The drawings that accompany the detailed description can be briefly described as follows:

[0005] Figure 1 is a general longitudinal schematic sectional view of an exemplary rocket engine;

[0006] Figure 2 is an expanded schematic sectional view of an injector assembly illustrating a single injector according to one non-limiting embodiment; and [0007] Figure 3 is an expanded schematic sectional view of a flow control assembly according to one non-limiting embodiment.

DETAILED DESCRIPTION

[0008] Figure 1 illustrates a general schematic view of a rocket engine 10. The engine 10 generally includes a nozzle assembly 12, a fuel system 14, an oxidizer system 16 and an ignition system 18. A combustion chamber wall 20 along a thrust axis A generally defines a thrust chamber 22, a combustion chamber 24 upstream of the thrust chamber 22, and a combustion chamber throat 26 therebetween. Although a particular rocket engine 10 is schematically illustrated it should be appreciate that various other rocket engine, aero engines, ramjets and other combustion systems will also benefit hereby.

[0009] An injector assembly 28 includes a multitude of fuel/oxidizer injector elements 30 that communicate through an injector face 32 into the combustion chamber 24. The fuel/oxidizer injector elements 30 receive fuel via a fuel manifold 34 in communication with the fuel system 14 and an oxidizer manifold 36 in communication with the oxidizer system 16. The fuel manifold 34 may receive fuel that may first traverse through the combustion chamber wall 20 to facilitate cooling of the nozzle assembly 12.

[0010] With reference to Figure 2, the injector assembly 28 generally includes a faceplate 40 and an inter-propellant plate 42 which separates the fuel manifold 34 and the oxidizer manifold 36. The faceplate 40 includes numerous fuel sleeves 44 through which a conduit 46 from the inter-propellant plate 42 passes. The fuel sleeves 44 includes a multiple of apertures 48 that communicate with an annulus 50 that surrounds the conduit 46 and is open to the combustion chamber 24. [0011] The inter-propellant plate 42 defines an additive manufacture support structure 52 having a cavity 54 therein that may, for example, communicate with a first passage 56 and a second passage 58. That is, the additive manufacture support structure 52 may form all or part of the inter-propellant plate 42 within which the cavity 54 is defined. The first passage 56 may extend through a boss 60 on the oxidizer manifold 36 side of the inter-propellant plate 42 and the second passage 58 may be in communication with the conduit 46. It should be appreciated that additional passages may also be in communication with the cavity 54.

[0012] Within the cavity 54, a non-integral part 62 such as a conical check valve prevents back flow from the combustion chamber 24. The cavity 54, non-integral part 62 and passages 56, 58 define a flow control device for each injector element 30 of the inter-propellant plate 42. As the inter-propellant plate 42 includes hundreds of injector elements 30, each of which may benefit from a check valve to prevent back-flow, an additive manufacturing process beneficially permits ready incorporation during manufacture. One additive manufacturing process includes powder bed metallurgy in which layers of powder alloy such as Inconel or other material is sequentially build-up by systems from, for example, Concept Laser of Lichtenfels, DE and EOS of Munich, DE.

[0013] During the additive manufacturing process, the cavity 54 is formed with the non-integral part 62 movably manufactured therein by selectively non-fusing of powder in at least some locations where the non-integral part 62 would otherwise abut the supporting structure such as the conduit 46. Upon completion of the non-integral part 62, a layer of powder may be selectively not fused to render the non-integral part 62 free to move within the cavity 54. As defined herein "non-integral" is defined as not connected to the support structure 52, however, even a slight connection may result in manufacture of the non-integral part 62 that then breaks away in use.

[0014] The additive manufacture support structure 52 is then completed such that the non-integral part 62 has a geometry that could not escape from the cavity 54 even through the largest passage 56, 58. In that regard, the non-integral part 62 is trapped within, but remains free to move or float, within the cavity 54 without the potential for leakage from an assembled structure.

[0015] The non-integral part 62 in the disclosed non-limiting embodiment may be corneal in shape with a tip 64 directed into an inflow passage to, for example, reduce back flow. The geometry of the non-integral part 62 may be selected based on the particular application. For example, the shape of the non-integral part may be akin to a reed, it may be rectangular boxed, cylindrical or other. Furthermore, in one disclosed non-limiting embodiment, the non-integral part 62 may rest upon a seat 66 within the cavity 54. The non-integral part 62 may thereby be positioned at particular locations at predefined operational conditions.

[0016] Although illustrated in the disclosed, non-limiting embodiment as an inter- propellant plate 42 of a rocket engine, the additive manufacture support structure 52 may be incorporated in other machines. For example, air-breathing engines or other systems may include, but are not limited to, tubes, conduits, flow bodies, vessels and other structures from which integral flow-control elements may benefit. Also, various non-integral parts such as swirl elements, diffusers, atomization nozzles, beads, obstructions, catalysts, and others will also benefit herefrom.

[0017] With reference to Figure 3, another disclosed, non-limiting embodiment, includes a multiple of non-integral parts 62' contained within a cavity 54'. The multiple of non- integral parts 62' may be spheres or other shapes that facilitate agitation of a fluid such as a propellant which passes through the cavity 54'.

[0018] It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should also be understood that although a particular component arrangement is disclosed in the illustrated embodiment, other arrangements will benefit herefrom.

[0019] Although the different non-limiting embodiments have specific illustrated components, the embodiments of this invention are not limited to those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments.

[0020] Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated and will still benefit from the present disclosure.

[0021] The foregoing description is exemplary rather than defined by the limitations within. Various non-limiting embodiments are disclosed herein, however, one of ordinary skill in the art would recognize that various modifications and variations in light of the above teachings will fall within the scope of the appended claims. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced other than as specifically described. For that reason the appended claims should be studied to determine true scope and content.

Claims

CLAIMS What is claimed:

1. An apparatus, comprising:

an additive manufacture housing that at least partially defines a cavity and a passage in fluid communication therewith; and

an additive manufacturing non-integral part movably disposed within said cavity, said non-integral part defines a geometry that cannot fit through said passage.

2. The apparatus as recited in claim 1, wherein said additive manufacturing housing includes no welds, no joints and no bonding proximate said cavity.

3. The apparatus as recited in claim 1, wherein said additive manufacturing non- integral part is conical.

4. The apparatus as recited in claim 3, wherein said additive manufacturing non- integral part is positioned with a point toward one of said multiple of passages.

5. The apparatus as recited in claim 1, wherein said additive manufacturing non- integral part is at least partially supported upon a ledge within said cavity.

6. The apparatus as recited in claim 1, wherein said additive manufacturing housing forms a portion of an inter-propellant plate.

7. The apparatus as recited in claim 1, wherein said additive manufacturing housing is manufactured via a powder bed additive manufacturing process.

8. The apparatus as recited in claim 1, wherein said additive manufacturing non- integral part is a check valve.

9. The apparatus as recited in claim 1, wherein said additive manufacturing non- integral part includes a multiple of spheres.

10. An injector assembly for a rocket engine comprising: an inter-propellant plate that at least partially defines a cavity with a first passage and a second passage in communication with said cavity, said inter-propellant plate manufactured via a powder bed additive manufacturing process; and a non-integral part movably disposed within said cavity, said non-integral part defines a geometry that cannot fit through either said first passage or said second passage, said non-integral part manufactured via a powder bed additive manufacturing process.

11. The injector assembly as recited in claim 10, wherein said inter-propellant plate includes no welds, no joints and no bonding proximate said cavity.

12. The injector assembly as recited in claim 10, wherein said non-integral part is a check valve.

13. The injector assembly as recited in claim 12, wherein said check valve is positioned with a point toward said first passage.

14. The injector assembly as recited in claim 13, wherein said check valve is at least partially supported upon a ledge within said cavity.