US-20260126176-A1 - CHAMBER FOR ROTATING DETONATION ENGINE AND WALL OBSTACLES FOR SAME

Abstract

A combustor for a rotating detonation engine includes an outer tapered wall extending along an axis; an inner tapered wall extending along the axis, wherein the inner tapered wall is positioned within the outer tapered wall to define an annular combustion chamber having an annular gap between the outer tapered wall and the inner tapered wall, wherein the outer tapered wall is moveable relative to the inner tapered wall along the axis, and wherein movement of the outer tapered wall relative to the inner tapered wall changes the annular gap of the annular combustion chamber. Obstacles can be positioned on either or both of inner and outer wall to enhance turbulence within the combustion chamber.

Inventors

• Christopher Britton Greene
• Peter AT Cocks
• Xiaoyi Li
• James M. Donohue

Assignees

• RTX CORPORATION

Dates

Publication Date

20260507

Application Date

20251229

Claims (20)

1. 1 . A combustor for a rotating detonation engine, the combustor comprising: an outer tapered wall extending along an axis; an inner tapered wall extending along the axis, wherein the inner tapered wall is positioned within the outer tapered wall to define an annular combustion chamber having an annular gap between the outer tapered wall and the inner tapered wall, wherein the outer tapered wall is moveable relative to the inner tapered wall along the axis, and wherein movement of the outer tapered wall relative to the inner tapered wall changes the annular gap of the annular combustion chamber.
2. 2 . The combustor of claim 1 , wherein at least one of the outer tapered wall and the inner tapered wall is at least partially conical in shape.
3. 3 . The combustor of claim 1 , wherein the annular combustor chamber has an inlet end and an outlet end, and wherein the outer tapered wall and the inner tapered wall are parallel between the inlet end and the outlet end.
4. 4 . The combustor of claim 1 , wherein the annular combustor chamber has an inlet end and an outlet end, and wherein the outer tapered wall and the inner tapered wall are divergent between the inlet end and the outlet end.
5. 5 . The combustor of claim 1 , wherein the annular combustor chamber has an inlet end and an outlet end, and wherein the outer tapered wall and the inner tapered wall are convergent between the inlet end and the outlet end.
6. 6 . The combustor of claim 1 , further comprising a movement mechanism for imparting relative movement to the outer tapered wall relative to the inner tapered wall.
7. 7 . The combustor of claim 6 , further comprising a control unit communicated with operating parameters of the rotating detonation engine and with the movement mechanism, the control unit being configured and adapted to move at least one of the outer tapered wall and the inner tapered wall relative to the other of the outer tapered wall and the inner tapered wall based upon the operating parameters.
8. 8 . The combustor of claim 1 , wherein the outer tapered wall has an inner surface defining an outer diameter of the annular combustor chamber, and wherein the inner tapered wall has an outer surface defining an inner diameter of the annular combustor chamber, and further comprising at least one flow obstacle on at least one of the inner surface and the outer surface.
9. 9 . The combustor of claim 8 , wherein the flow obstacle comprises an elongate structure extending along the at least one of the inner surface and the outer surface and oriented at an angle (α) relative to the axis of between 0 and 30 degrees.
10. 10 . A rotating detonation engine system, comprising: an inlet for fuel and oxidant to an annular combustion chamber of a rotating detonation combustor; an outer tapered wall extending along an axis; an inner tapered wall extending along the axis, wherein the inner tapered wall is positioned within the outer tapered wall to define the annular combustion chamber having an annular gap between the outer tapered wall and the inner tapered wall, wherein the outer tapered wall is moveable relative to the inner tapered wall along the axis, and wherein movement of the outer tapered wall relative to the inner tapered wall changes the annular gap of the annular combustion chamber; and an exhaust communicated with an outlet of the annular combustion chamber.
11. 11 . The system of claim 10 , wherein at least one of the outer tapered wall and the inner tapered wall is at least partially conical in shape.
12. 12 . The system of claim 10 , wherein the annular combustor chamber has an inlet end and an outlet end, and wherein the outer tapered wall and the inner tapered wall are parallel between the inlet end and the outlet end.
13. 13 . The system of claim 10 , wherein the annular combustor chamber has an inlet end and an outlet end, and wherein the outer tapered wall and the inner tapered wall are divergent between the inlet end and the outlet end.
14. 14 . The system of claim 10 , wherein the annular combustor chamber has an inlet end and an outlet end, and wherein the outer tapered wall and the inner tapered wall are convergent between the inlet end and the outlet end.
15. 15 . The system of claim 10 , further comprising a movement mechanism for imparting relative movement to the outer tapered wall relative to the inner tapered wall.
16. 16 . The system of claim 15 , further comprising a control unit communicated with operating parameters of the rotating detonation engine and with the movement mechanism, the control unit being configured and adapted to move the outer tapered wall relative to the inner tapered wall based upon the operating parameters.
17. 17 . The system of claim 10 , wherein the outer tapered wall has an inner surface defining an outer diameter of the annular combustor chamber, and wherein the inner tapered wall has an outer surface defining an inner diameter of the annular combustor chamber, and further comprising at least one flow obstacle on at least one of the inner surface and the outer surface.
18. 18 . The system of claim 17 , wherein the flow obstacle comprises an elongate structure extending along the at least one of the inner surface and the outer surface and oriented at an angle (α) relative to the axis of between 0 and 30 degrees.
19. 19 . A combustor for a rotating detonation engine, the combustor comprising: an outer wall extending along an axis; an inner wall extending along the axis, wherein the inner wall is positioned within the outer wall to define an annular combustion chamber having an annular gap between the outer wall and the inner wall, wherein the outer wall has an inner surface defining an outer diameter of the annular combustor chamber, and wherein the inner wall has an outer surface defining an inner diameter of the annular combustor chamber, and further comprising at least one flow obstacle on at least one of the inner surface and the outer surface.
20. 20 . The combustor of claim 19 , wherein the flow obstacle comprises an elongate structure extending along the at least one of the inner surface and the outer surface and oriented at an angle (α) relative to the axis of between 0 and 30 degrees.

Description

CROSS-REFERENCE TO RELATED APPLICATION Benefit is claimed of U.S. Patent Application No. 63/170,243, filed Apr. 2, 2021, and entitled CHAMBER FOR ROTATING DETONATION ENGINE AND WALL OBSTACLES FOR SAME, the disclosure of which is incorporated by reference herein in its entirety as if set forth at length. BACKGROUND The disclosure relates to rotating detonation engines and, more particularly, to structures and configuration of the walls defining the combustor of rotating detonation engines. Rotating detonation engines are being considered for use to meet a wide variety of engine or propulsion needs. A rotating detonation engine (RDE) utilizes a controlled feed of fuel and oxidant to an annular chamber to generate a detonation wave rotating around the chamber at high speeds to generate thrust from an outlet of the chamber. Proper conditions to start and then maintain rotating detonation in the combustor are needed. Some environments of use of an RDE require a wide operability range in addition to maintaining stable detonation operation. One such environment is in a ramjet engine. Another aspect of stable operation of an RDE is obtaining good mixing of the fuel and oxidizer. There is a need for an RDE with a wide operability range. Further, there is a need for such an RDE wherein the fuel and oxidizer are well mixed to strengthen and stabilize the detonation process. SUMMARY In one non-limiting configuration, a combustor for a rotating detonation engine comprises an outer tapered wall extending along an axis; an inner tapered wall extending along the axis, wherein the inner tapered wall is positioned within the outer tapered wall to define an annular combustion chamber having an annular gap between the outer tapered wall and the inner tapered wall, wherein the outer tapered wall is moveable relative to the inner tapered wall along the axis, and wherein movement of the outer tapered wall relative to the inner tapered wall changes the annular gap of the annular combustion chamber. In another non-limiting configuration, at least one of the outer tapered wall and the inner tapered wall is at least partially conical in shape. In still another non-limiting configuration, the annular combustor chamber has an inlet end and an outlet end, and wherein the outer tapered wall and the inner tapered wall are parallel between the inlet end and the outlet end. In a further non-limiting configuration, the annular combustor chamber has an inlet end and an outlet end, and the outer tapered wall and the inner tapered wall are divergent between the inlet end and the outlet end. In a still further non-limiting configuration, the annular combustor chamber has an inlet end and an outlet end, and the outer tapered wall and the inner tapered wall are convergent between the inlet end and the outlet end. In another non-limiting configuration, the combustor further comprises a movement mechanism for imparting relative movement to the outer tapered wall relative to the inner tapered wall. In still another non-limiting configuration, the combustor further comprises a control unit communicated with operating parameters of the rotating detonation engine and with the movement mechanism, the control unit being configured and adapted to move at least one of the outer tapered wall and the inner tapered wall relative to the other of the outer tapered wall and the inner tapered wall based upon the operating parameters. In a further non-limiting configuration, the outer tapered wall has an inner surface defining an outer diameter of the annular combustor chamber, and the inner tapered wall has an outer surface defining an inner diameter of the annular combustor chamber, and further comprising at least one flow obstacle on at least one of the inner surface and the outer surface. In a still further non-limiting configuration, the flow obstacle comprises an elongate structure extending along the at least one of the inner surface and the outer surface and oriented at an angle (α) relative to the axis of between 0 and 30 degrees. In another non-limiting configuration, a rotating detonation engine system, comprises an inlet for fuel and oxidant to an annular combustion chamber of a rotating detonation combustor; an outer tapered wall extending along an axis; an inner tapered wall extending along the axis, wherein the inner tapered wall is positioned within the outer tapered wall to define the annular combustion chamber having an annular gap between the outer tapered wall and the inner tapered wall, wherein the outer tapered wall is moveable relative to the inner tapered wall along the axis, and wherein movement of the outer tapered wall relative to the inner tapered wall changes the annular gap of the annular combustion chamber; and an exhaust communicated with an outlet of the annular combustion chamber. In still another non-limiting configuration, at least one of the outer tapered wall and the inner tapered wall is at least partially conical in shape. In