SIEVE RDE INJECTOR WITH VARIABLE PRESSURE DROP CAPABILITY

Description

BACKGROUND

The disclosure relates to rotating detonation engines and, more particularly, to structures and wall configuration 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 and produce thrust from an outlet of the chamber. Features for promoting fuel-oxidant mixing and maintaining a combustor pressure drop at various operating conditions are needed.

SUMMARY

A combustor according to an example of this disclosure includes an inner wall, an outer wall, an end wall, and a valve element. The outer wall and the inner wall are spaced to form a combustion chamber, and the end wall joins the inner wall to the outer wall. A plurality of fuel ports extends through one of the inner wall and the outer wall. A plurality of oxidant openings extends through one or more of the inner wall, the outer wall, and the end wall. The valve element is arranged concentrically with one or more of the inner wall and the outer all and is translatable from a first position towards a second position and from the second position towards the first position. The valve element overlaps at least one oxidant opening as the valve element translates towards the second position.

A combustor assembly according to an example of this disclosure includes a case module and a combustor. The case module includes an inner case and an outer case. The combustor is disposed between the inner case and the outer case to form a plenum. The combustor includes an inner wall, an outer wall, an end wall, and a valve element. The outer wall and the inner wall are spaced to form a combustion chamber, and the end wall joins the inner wall to the outer wall. A plurality of fuel ports extends through one of the inner wall and the outer wall. A plurality of oxidant openings extends through one or more of the inner wall, the outer wall, and the end wall to fluidly connect the plenum to the combustion chamber. The valve element is arranged concentrically with one or more of the inner wall and the outer all and is translatable from a first position towards a second position and from the second position towards the first position. The valve element overlaps at least one oxidant opening as the valve element translates towards the second position.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an example combustor for a rotating detonation engine (FDE).

FIG. 2 is an isometric section view depicting additional details of the example combustor.

FIG. 3 is an isometric end view depicting the end wall of the example combustor depicted by FIG. 2.

FIG. 4 is an isometric section view depicting additional details of another example combustor.

FIG. 5 is an isometric end view depicting the end wall of the example combustor depicted by FIG. 4.

DETAILED DESCRIPTION

FIG. 1 is a cross-sectional view of combustor 10 for use with a rotating detonation engine (RTE). Combustor 10 includes inner wall 12, outer wall 14, end wall 16, fuel manifold 18, and valve element 20.

Combustor 10 extends longitudinally along engine axis A within case module 22. Inner wall 12 and outer wall 14 are spaced radially with respect to engine axis A to define combustion chamber 24. Inner wall 12 and outer wall 14 circumscribe engine axis A such that combustion chamber 24 is annular. Inner wall 12 is spaced radially outward from inner case 22A of case module 22 to define inner annular plenum 26. Outer wall 14 is spaced radially inward from outer case 22B of case module 22 to define outer annular plenum 28. End wall 16 extends between and joins inner wall 12 to outer wall 14 to define inlet end 30 of combustor 10. Inner wall 12 and outer wall 14 extend longitudinally along engine axis A to outlet end 32. Inner annular plenum 26 and outer annular plenum 28 receive oxidant from inlet plenum 34, which defines a region between inner case 22A and outer case 22B that is upstream from end wall 16.

Fuel manifold 18 extends circumferentially along inner wall 12 and/or outer wall 14 to enclose fuel plenum 36. Fuel plenum 36 is placed in fluid communication with fuel source 37. Fuel ports 38 extend through inner wall 12 and/or outer wall 14 to place fuel plenum 36 in fluid communication with combustion chamber 24. Fuel ports 38 include one or more holes arranged in a circumferentially-spaces and/or axial spaced array of fuel ports 38. Fuel ports 38 can be orientated normally with respect to a surface of inner wall 12 or a surface of outer wall 14 bounding combustion chamber 24. In other examples, fuel ports 38 can be orientated at an oblique angle with respect to the combustion surface of inner wall 12 or the combustion surface of outer wall 14. Fuel ports 38 are depicted with a circular cross section. However, in other examples, fuel ports 38 can be elliptical, ovular, oblong, square, or rectangular, among other possible cross-sections.

Combustor 10 can be restrained at inlet end 30, at outlet end 32, or at a location in between inlet end 30 and outlet end 32 of combustor 10. For example, a support structure may engage inner wall 12 and/or outer wall 14 to restrain combustor 10 radially and/or axially with respect to engine axis A. For example, support structure 39 can span between and connect inner wall 12 or fuel manifold 18 to inner case 22A, or span between and connect outer wall 14 to outer case 22B. The support structure may engage radially inner surface 18A and axial upstream surface 18B of fuel manifold 18 to restrain combustor 10 in the radial and axial direction, respectively, with respect to engine axis A. Support structure 39 may include one or more struts, which can be used to supply fuel to fuel plenum 36 that span between fuel manifold 18 and inner case 22A for example. In other examples, combustor 10 can be supported at or near outlet end 32. However, such examples may require cooling of the support structure to counteract heat flux produced by combustion.

At inlet end 30 of combustor 10, inner wall 12, outer wall 14, and/or end wall 16 can include oxidant openings 40, which extend through respective portions thereof. Oxidant openings 40 place inner annular plenum 26, outer annular plenum 28, and/or inlet plenum 34 in fluid communication with combustion chamber 24. Example of oxidant openings 40 can include one or more holes, apertures, slots, and/or vanes, among other possible oxidant openings 40. Oxidant openings 40 have a hydraulic diameter sized to meter oxidant flow from inner annular plenum 26, outer annular plenum 28, and inlet plenum 34 into combustion chamber 24. In some examples, oxidant openings 40 have a length-to-hydraulic-diameter ratio (L/D) greater than 1.5. In other examples, the length-to-hydraulic-diameter ratio (L/D) is greater than 2.0. The cross-section of oxidant openings 40 are depicted as circular in FIG. 1, FIG. 2, and FIG. 3. In other examples, one or more oxidant openings 40 can have an elliptical, an ovular, an oblong, a rectangular, a diamond, a square cross-section, among other possible cross-sectional shapes. In still other examples, oxidant openings 40 are defined as oblong slots or aerodynamically shaped vanes as depicted in FIG. 4 and FIG. 5.

Oxidant openings 40 have an angular orientation defined between an axis of each oxidant opening and a surface of inner wall 12, outer wall 14, or end wall 16 bounding combustion chamber 24. In some examples, oxidant openings 40 are normal to a respective surfaces of inner wall 12, outer wall 14, or end wall 16. In other examples, oxidant openings 40 define an oblique angle with respect to a surface of inner wall 12, outer wall 14, or end wall 16. Oxidant openings 40 with an upstream orientation or a downstream orientation are angled to discharge into combustion chamber 24 with a velocity component towards outlet end 32 or inlet end 30, respectively. Oxidant openings 40 may have a clockwise orientation or a counterclockwise orientation in which oxidant openings 40 are oriented to discharge into combustion chamber 24 with a circumferentially clockwise velocity component or a circumferentially counterclockwise velocity component, when viewed along engine axis A towards outlet end 32. Oxidant openings 40 can be divided into one or more groups, each group characterized by a length-to-diameter ratio (L/D), angular orientation, number of openings, and/or pattern of openings.

Valve element 20 is a moveable member that translates along inner wall 12 or outer wall 14 to obstruct one or more oxidant openings 40, but less than all oxidant openings 40. Valve element 20 can be a cylinder or ring disposed concentrically with respect to inner wall 12 and/or outer wall 14. In a first position (e.g., an open position), valve element 20 is offset from oxidant openings 40 such that all oxidant openings 40 fluidly communicate with combustion chamber 24 from one of inner annular plenum 26, outer annular plenum 28, and inlet plenum 34. In a second position (e.g., a closed position), valve element 20 is displaced axially along engine axis A relative to the first position to axially overlap and obstruct one or more oxidant openings 40 and less than all oxidant openings 40. In some examples, valve element 20 can be positioned at any intermediate position between the first position and the second position. By covering or partially covering some or all of oxidant openings 40, valve element 20 can vary a net oxidant inlet area into combustion chamber 24 and, hence, vary a pressure drop and/or flow rate of oxidant flowing into combustion chamber 24. For instance, valve element 20 can displace to vary a flow rate of oxidant into combustion chamber 24 while maintaining a pressure drop associated with oxidant flow within a target pressure drop range.

Actuator 42 and, in some examples, linkage 44 may act together to translate valve element 20. Actuator 42 can be any mechanical, electrical, hydraulic, pneumatic, or magnetic actuator suitable for use with combustor 10, among other possible actuator types. Actuator 42 can be directly attached to valve element 20 in some examples and, accordingly, linkage 44 is not necessary. In other examples, linkage 44 couples actuator 42 to valve element 20 using any suitable mechanical, electrical, hydraulic, or pneumatic coupling such that movement of actuator 42 translates to displacement of valve element 20.

Some examples of combustor 10 are further associated with controller 46. Controller 46 is an electronic device that is connected to actuator 42 via a wireless and/or a wired connection as indicated by dashed lines 48. Controller 46 can be a computer, an engine control unit, a control module integrated with an engine control unit, a control module discrete from an engine control unit, and a full authority digital engine (or electronics) controller, among other possible examples. While the following disclosure refers to a controller (singular), the functions attributed to a single controller can be distributed among multiple controllers 46 in other examples. That is, functionality attributed herein to controller 46 can, in certain examples, be distributed among multiple controllers 46.

Controller 46 can store in memory a displacement schedule for valve element 20 that relates an axial position of valve element 20 between the first position and the second position, inclusive, to one or more operating parameters of combustor 10, or a system or vehicle with which combustor 10 is operatively associated. For instance, the displacement schedule can relate the position of valve element 20 relative to one or more of altitude, ambient pressure, and/or ambient temperature. In other examples, controller 46 can receive signals representative of one or more internal parameters of combustor 10. For example, controller may receive a differential pressure signal representative of a pressure within combustion chamber 24 relative to a pressure within inlet plenum 34, inner annular plenum 26, and/or outer annular plenum 28. Likewise, controller 46 may receive multiple signals, each signal from a different pressure sensor. For example, combustor 10 may include a first sensor configured to output a signal representative of a gauge pressure or an absolute pressure within combustion chamber 24. A second sensor or second sensors can be configured to each output a signal representative of a gauge pressure or ambient pressure within inlet plenum 34, inner annular plenum 26, and/or outer annular plenum 28. Based on the signals representative of pressure within combustion chamber 24 and pressure within one or more of plenums 26, 28, and 34, controller 46 may calculate a differential pressure.

However determined, controller 46 may cause actuator 42 to translate valve element 20 to a target position based on a measured or calculated differential pressure described above in order to maintain the differential pressure within a target differential pressure range. The target differential pressure range can be associated with a minimum differential pressure necessary to prevent reverse propagation of the detonation wave during operation. A maximum differential pressure can be associated with a minimum flow rate required to maintain stable detonation wave propagation within combustion chamber 24.

In operation, combustor 10 operates within an oxidant mass flow rate range and a fuel flow rate range. Inlet plenum 34, inner annular plenum 26, and/or outer annular plenum 28 receive oxidant, which passively flows into combustion chamber 24 through oxidant openings in one or more of inner wall 12, outer wall 14, and end wall 16. Fuel is received within fuel plenum 36, distributed circumferentially about combustor 10, and passively flows into combustion chamber 24 via fuel ports 38. Fuel and oxidant mix within combustion chamber 24 to achieve an oxidant-fuel ratio. Combustion initiates by, for example, activating an ignitor or otherwise introducing sufficient energy into combustion chamber 24 to initiate combustion. Under continuous flow of oxidate and fuel into combustion chamber 24, a detonation wave develops within combustion chamber 24 that propagates circumferentially and axially throughout combustion chamber. As the oxidant-fuel mixture is consumed by the detonation wave and subsequent deflagration, additional oxidant and fuel passively refills combustion chamber 24 thereby creating a continuously propagating detonation wave within combustion chamber 24. As flow rate of oxidant varies with changing ambient or operational conditions, valve element 20 can reduce or increase the oxidant inlet area to maintain differential pressure into combustion chamber 24 within a target range.

FIG. 2 is a perspective section view of combustor 10A, and FIG. 3 is a perspective end view of combustor 10A, depicting a particular example of combustor 10 along with additional details of oxidant openings 40. As depicted by FIG. 2 and FIG. 3, combustor 10A includes multiple groups of oxidant openings 40 arranged through inner wall 12 and end wall 16. Outer wall 14 of combustor 10A does not include any oxidant openings 40.

Inner wall 12 includes upstream oxidant openings 40A and downstream oxidant openings 40B located upstream and downstream relative to fuel ports 38 respectively. Upstream oxidant openings 40A and downstream oxidant openings 40B have an oblique orientation with respective to bounding surfaces of combustion chamber 24. Upstream oxidant openings 40A are angled in a downstream clockwise direction. Downstream oxidant openings 40B are angled in a downstream direction only.

Further as depicted, end wall 16 includes inner oxidant openings 40C and outer oxidant openings 40D. Inner oxidant openings 40C have circular cross-sections and have an oblique orientation oriented in a clockwise orientation with respect to surface bounding combustion chamber 24. Outer oxidant openings 40D have an oblique orientation angled in a counterclockwise direction.

Each of oxidant openings 40A, 40B, 40C, and 40D have circular cross-sections and length-to-hydraulic-diameter ratios greater than 2.0, for example, a length-to-hydraulic-diameter ratio of about 2.4. In each instance, the oblique orientation of oxidant openings 40A and 40B blocks all radial lines of sight between inner annular plenum 26 and combustion chamber 24. Similarly, the oblique orientation of oxidant openings 40C and 40D blocks axial lines of sight between inlet plenum 34 and combustion chamber 24. Radially adjacent rows of oxidant openings 40C and 40D and axially adjacent rows of oxidant openings 40A and 40B are circumferentially offset to form respective grid patterns, which operate to promote mixing of oxidant and fuel within combustion chamber 24. Furthermore, upstream oxidant openings 40A, inner oxidant openings 40C, and outer oxidant openings 40D define an alternating clockwise and counterclockwise orientation such that upstream oxidant openings 40A are angled in a clockwise direction, inner oxidant openings 40C are angled in a counterclockwise orientation, and outer oxidant openings are angled in a clockwise rotation. The alternating circumferential orientation of oxidant openings 40A, 40C, and 40D creates shear layers between groups of oxidant openings and thereby promotes mixing of oxidant and fuel near inlet end 30 of combustion chamber 24. In other examples, the alternating circumferential orientation can be reversed such that upstream oxidant openings 40A and outer oxidant openings 40D have a counterclockwise orientation and inner oxidant openings 40C have a clockwise orientation.

Further as depicted by FIG. 2 and FIG. 3, valve element 20 is a cylinder that has a first position (i.e., an open position) offset downstream from oxidant openings 40B and fuel ports 38. Valve element 20 is translatable in an upstream direction along engine axis A to the second position (i.e., the blocked position) in which some of oxidant openings 40B (e.g., three of four rows of oxidant openings 40) are covered by valve element 20. Likewise, valve element 20 is translatable in a downstream direction along engine axis A towards the first position. As such, the pressure drop of oxidant flowing into combustion chamber 24 can be increased as valve element 20 translates from the first position to the second position, or decreased as valve element 20 translates from the second position to the first position. Combustor 10A can be associated with controller 46 as described above to vary the position of valve element 20 based on a calculated or measured differential pressure, or based on a schedule that relate the position of valve element 20 to one or more external parameters (e.g., altitude, ambient temperature, and/or ambient pressure) and/or to one or more internal parameters (e.g., pressure and/or flow rate within combustion chamber 24, inlet plenum 34, inner annular plenum 26, and/or outer annular plenum 28, pressure and/or flow rate within fuel plenum 36, among other possible internal parameters).

FIG. 4 is a perspective section view of combustor 10B, and FIG. 5 is a perspective end view of combustor 10B, depicting another example of combustor 10 along with additional details of oxidant openings 40. As depicted by FIG. 4 and FIG. 5, combustor 10B includes multiple groups of oxidant openings 40 arranged through inner wall 12 and end wall 16, each of the groups of oxidant openings 40 having a slot configuration. Outer wall 14 of combustor 10B does not include oxidant openings 40.

Inner wall 12 includes upstream oxidant openings 40A and downstream oxidant openings 40B located upstream and downstream relative to fuel ports 38 respectively. Upstream oxidant openings 40A and downstream oxidant openings 40B have an oblique orientation with respective to bounding surfaces of combustion chamber 24. Upstream oxidant openings 40A are angled in a counterclockwise direction. Downstream oxidant openings 40B are angled in a downstream direction.

Further as depicted, end wall 16 includes inner oxidant openings 40C, outer oxidant openings 40D, and intermediate oxidant openings 40E. Inner oxidant openings 40C are arranged proximate to inner wall 12 (i.e., a radially innermost group of oxidant openings 40). Outer oxidant openings 40D are arranged proximate to outer wall 14 (i.e., a radially outermost group of oxidant openings 40). Intermediate oxidant openings 40E are disposed radially between inner oxidant openings 40C and outer oxidant openings 40D. Inner oxidant openings 40C and outer oxidant openings 40D have an oblique orientation oriented in a clockwise orientation with respect to surface bounding combustion chamber 24. Upstream oxidant openings 40A and intermediate oxidant openings 40E have an oblique orientation angled in a counterclockwise direction.

Each of oxidant openings 40A, 40B, 40C, 40D, and 40E have an oblong cross-section and length-to-hydraulic-diameter ratios greater than 2.0. In each instance, the oblique orientation of oxidant openings 40A and 40B blocks all radial lines of sight between inner annular plenum 26 and combustion chamber 24. Similarly, the oblique orientation of oxidant openings 40C, 40D, and 40E blocks axial lines of sight between inlet plenum 34 and combustion chamber 24. Upstream oxidant openings 40A, inner oxidant openings 40C, intermediate oxidant openings 40E, and outer oxidant openings 40D are slots with aerodynamically profiled sidewalls. That is to say, two opposite walls bounding oxidant openings 40A, 40C, 40D, and 40E form airfoils having complimentary convex and concave flanks. As depicted, two opposite walls bounding downstream oxidant openings 40B are parallel to a radial direction and, as such, are not aerodynamically shaped slots.

Furthermore, upstream oxidant openings 40A, inner oxidant openings 40C, intermediate oxidant openings 40E, and outer oxidant openings 40D define an alternating clockwise and counterclockwise orientation such that upstream oxidant openings 40A and intermediate oxidant openings 40E are angled in a counterclockwise direction while inner oxidant openings 40C and outer oxidant openings 40D are angled in a clockwise orientation. The alternating circumferential orientation of oxidant openings 40A, 40C, 40D, 40E creates shear layers between groups of oxidant openings and thereby promotes mixing of oxidant and fuel near inlet end 30 of combustion chamber 24. In other examples, the alternating circumferential orientation can be reversed such that upstream oxidant openings 40A and intermediate oxidant openings 40E have a clockwise orientation and inner oxidant openings 40C and outer oxidant openings 40D have a counterclockwise orientation.

Further as depicted by FIG. 4 and FIG. 5, valve element 20 is a cylinder that has a first position (i.e., an open position) offset downstream from oxidant openings 40D and fuel ports 38. Valve element 20 is translatable in an upstream direction along engine axis A to the second position (i.e., the blocked position) in which some of oxidant openings 40B (e.g., two of three rows of slot-shaped oxidant openings 40B) are covered by valve element 20. As depicted, valve element 20 is shown in the second position. Likewise, valve element 20 is translatable in a downstream direction along engine axis A towards the first position. As such, the pressure drop of oxidant flowing into combustion chamber 24 can be increased as valve element 20 translates from the first position to the second position, or decreased as valve element 20 translates from the second position to the first position. Combustor 10B can be associated with controller 46 as described above to vary the position of valve element 20 based on a calculated or measured differential pressure, or based on a schedule that relate the position of valve element 20 to one or more external parameters (e.g., altitude, ambient temperature, and/or ambient pressure) and/or to one or more internal parameters (e.g., pressure and/or flow rate within combustion chamber 24, inlet plenum 34, inner annular plenum 26, and/or outer annular plenum 28, pressure and/or flow rate within fuel plenum 36, among other possible internal parameters).

Accordingly, the foregoing examples provide a combustor for a rotating detonation engine that includes a variable oxidant inlet area. A variable oxidant inlet area facilitates operation of rotating detonation engine within a wider range of operational conditions characterized by one or more of ambient pressure, ambient temperature, oxidant mass flow rate, oxidant pressure, and oxidant temperature. Using valve element 20 to block and/or obstruct one or more oxidant openings 40, but less than all oxidant openings of combustor 10, controller 46 can cause combustion chamber 24 to operate within a target differential pressure range and thereby maintain a stable detonation wave within combustion chamber 24 despite varying inlet conditions.

In the foregoing description, the terms “upstream” and “downstream” refer to the intended flow direction through combustors 10, 10A, and 10B, which flows from end wall 16 towards outlet end 32. As depicted by FIG. 1, “upstream” refers to a direction generally towards end wall 16 or the left side of FIG. 1 whereas “downstream refers to a direction generally away from end wall 16 or towards the right side of FIG. 1. Terms “inner” and “outer” refer to relative radial dimensions of combustor 10 with respect to engine axis A. “Axial” and “axially” refer to a direction parallel to engine axis A.

Discussion of Possible Embodiments

The following are non-exclusive descriptions of possible embodiments of the present invention.

A Combustor with Variable Oxidant Inlet Area

A combustor according to an example embodiment of this disclosure includes, among other possible things, an inner wall, an outer wall, an end wall, a plurality of fuel ports, a plurality of oxidant openings, and a valve element. The outer wall is spaced radially with respect to the inner wall to define a combustion chamber. The end wall joins the inner wall to the outer wall. The plurality of fuel ports extends through one of the inner wall and the outer wall. The plurality of oxidant openings extends through one or more of the inner wall, the outer wall, and the end wall. The valve element is disposed concentrically with one or more of the inner wall and the outer wall. The valve element is translatable from a first position towards a second position and from a second position towards a first position such that at least one oxidant opening of the plurality of oxidant openings as the valve element translates towards the second position.

The combustor of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components.

A further embodiment of the foregoing combustor, wherein the valve element can overlap less than all oxidant openings as the valve element translates towards the second position.

A further embodiment of any of the foregoing combustors can include a fuel plenum extending circumferentially about one of the inner wall and the outer wall and fluidly communicating with the plurality of fuel ports.

A further embodiment of any of the foregoing combustors, wherein the fuel ports can have an oblique orientation such that the fuel ports define one of a clockwise circumferential orientation and a counterclockwise circumferential orientation.

A further embodiment of any of the foregoing combustors, wherein at least some of the plurality of oxidant openings can have an oblique orientation that blocks line of sight into the combustion chamber when viewed along an engine axis and along a radial line relative to the engine axis.

A further embodiment of any of the foregoing combustors, wherein the plurality of oxidant openings can include upstream oxidant openings extending through the inner wall.

A further embodiment of any of the foregoing combustors, wherein the upstream oxidant openings can be disposed between the fuel ports and the end wall.

A further embodiment of any of the foregoing combustors, wherein the plurality of oxidant openings can include downstream oxidant openings extending through the inner wall.

A further embodiment of any of the foregoing combustors, wherein the downstream oxidant openings can be disposed between the fuel ports and an outlet end of the combustor opposite the end wall at an inlet end of the combustor.

A further embodiment of any of the foregoing combustors, wherein the upstream oxidant openings and the downstream oxidant openings can have a downstream orientation.

A further embodiment of any of the foregoing combustors, wherein the upstream oxidant openings can have one of clockwise downstream orientation and a counterclockwise downstream orientation.

A further embodiment of any of the foregoing combustors, wherein the plurality of oxidant openings can include inner oxidant openings extending through the end wall proximate inner wall.

A further embodiment of any of the foregoing combustors, wherein the plurality of oxidant openings can include outer oxidant openings extending through end wall proximate to outer wall.

A further embodiment of any of the foregoing combustors, wherein the outer oxidant openings can be radially outward from inner oxidant openings.

A further embodiment of any of the foregoing combustors, wherein one of the inner oxidant openings and the outer oxidant openings can have a clockwise orientation and the other of the inner oxidant openings and the outer oxidant openings can have a counterclockwise orientation.

A Combustor Assembly with a Variable Oxidant Inlet Area

A combustor assembly according to an example embodiment of this disclosure includes, among other possible things, a case module and a combustor. The case module includes an inner case and an outer case. The combustor is disposed between the inner case and the outer case to form a plenum. The combustor includes an inner wall, an outer wall, an end wall, a plurality of fuel ports, a plurality of oxidant openings, and a valve element. The outer wall is spaced radially with respect to the inner wall to form a combustion chamber. The end wall joins the inner wall to the outer wall. The plurality of fuel ports extends through one of the inner wall and the outer wall. The plurality of oxidant openings extends through one or more of the inner wall, the outer wall, and the end wall to fluidly connect the plenum to the combustion chamber. The valve element is disposed concentrically with one or more of the inner wall and the outer wall. The valve element is translatable from a first position towards a second position and from a second position towards a first position such that at least one oxidant opening of the plurality of oxidant openings as the valve element translates towards the second position.

The combustor assembly of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components.

A further embodiment of the foregoing combustor assembly, wherein the valve element can overlap less than all oxidant openings as the valve element translates towards the second position.

A further embodiment of any of the foregoing combustor assemblies can include a fuel plenum extending circumferentially about one of the inner wall and the outer wall and fluidly communicating with the plurality of fuel ports.

A further embodiment of any of the foregoing combustor assemblies, wherein the fuel ports can have an oblique orientation such that the fuel ports define one of a clockwise circumferential orientation and a counterclockwise circumferential orientation.

A further embodiment of any of the foregoing combustor assemblies, wherein at least some of the plurality of oxidant openings can have an oblique orientation that blocks line of sight into the combustion chamber when viewed along an engine axis and along a radial line relative to the engine axis.

A further embodiment of any of the foregoing combustor assemblies, wherein the plurality of oxidant openings can include upstream oxidant openings extending through the inner wall.

A further embodiment of any of the foregoing combustor assemblies, wherein the upstream oxidant openings can be disposed between the fuel ports and the end wall.

A further embodiment of any of the foregoing combustor assemblies, wherein the plurality of oxidant openings can include downstream oxidant openings extending through the inner wall.

A further embodiment of any of the foregoing combustor assemblies, wherein the downstream oxidant openings can be disposed between the fuel ports and an outlet end of the combustor opposite the end wall at an inlet end of the combustor.

A further embodiment of any of the foregoing combustor assemblies, wherein the upstream oxidant openings and the downstream oxidant openings can have a downstream orientation.

A further embodiment of any of the foregoing combustor assemblies, wherein the upstream oxidant openings can have one of clockwise downstream orientation and a counterclockwise downstream orientation.

A further embodiment of any of the foregoing combustor assemblies, wherein the plurality of oxidant openings can include inner oxidant openings extending through the end wall proximate inner wall.

A further embodiment of any of the foregoing combustor assemblies, wherein the plurality of oxidant openings can include outer oxidant openings extending through end wall proximate to outer wall.

A further embodiment of any of the foregoing combustor assemblies, wherein the outer oxidant openings can be radially outward from inner oxidant openings.

A further embodiment of any of the foregoing combustor assemblies, wherein one of the inner oxidant openings and the outer oxidant openings can have a clockwise orientation and the other of the inner oxidant openings and the outer oxidant openings can have a counterclockwise orientation.

While the invention has been described with reference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment(s) disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.