The present disclosure relates generally to the field of gas turbine engines and, more particularly, to rotating detonation combustors with a non-circular cross-section.
Some conventional turbo machines, such as gas turbine systems, are utilized to generate electrical power or to provide propulsion for aircraft. In general, gas turbine systems include a compressor, a combustor, and a turbine. Air may be drawn into a compressor, via its inlet end, where the air is compressed by passing through multiple stages of rotating blades and stationary nozzles. The compressed air is mixed with fuel and burned in a combustor, and the resulting combustion products (hot gases) are directed to a turbine to convert the thermal and kinetic energy into work.
Rotating detonation combustors, which are currently the subject of considerable worldwide research, are believed to offer an efficiency benefit over pulse detonation combustors and conventional deflagrative combustors. The combustion process begins when a fuel/oxidizer (e.g., air) mixture in a tube or pipe structure is ignited via a spark or another suitable ignition source to generate a compression wave. The compression wave is followed by a chemical reaction that transitions the compression wave to a detonation wave. The detonation wave travels circumferentially and axially through the combustion chamber defined by the tube. As air and fuel are fed into the combustion chamber, they are consumed by the detonation wave. As the detonation wave consumes air and fuel, combustion products traveling along the combustion chamber accelerate and are discharged from the combustion chamber.
Specifically, as shown in
The combustion products 22 flow through a fluid flow path in a turbine, which is defined between a plurality of rotating blades and a plurality of stationary nozzles disposed between the rotating blades, such that each set of rotating blades and each corresponding set of stationary nozzles defines a turbine stage. Typically, the rotation of the turbine blades also causes rotation of the compressor blades, which are coupled to the rotor.
In the development of rotating detonation combustors, computer modeling has generally used a circular cross-section to represent the annulus 4 between the inner wall 6 and the outer wall 8. However, it has been found that this circular architecture inhibits the efficient delivery of the combustion products 22 to the turbine section. Therefore, architectures having a shape more complementary to the inlet of the turbine section are desirable.
The present disclosure is directed to a rotating detonation combustor in which the cross-section of the annular combustion passage is non-circular. Specifically, the present rotating detonation combustor includes a forward wall, a radially inner wall, and a radially outer wall. The radially inner wall and the radially outer wall extend downstream from the forward wall around a longitudinal axis of the combustor, thus defining an annular passage between the radially inner wall and the radially outer wall. An air inlet and a fuel inlet are disposed proximate to the forward wall and in fluid communication with the annular passage. The cross-section of the annular passage, which can be elliptical or polygonal, is defined by arcuate and/or straight sides of the inner and outer walls.
The specification, directed to one of ordinary skill in the art, sets forth a full and enabling disclosure of the present system and method, including the best mode of using the same. The specification refers to the appended figures, in which:
Reference will now be made in detail to various embodiments of the present disclosure, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. Like or similar designations in the drawings and description have been used to refer to like or similar parts of the disclosure.
To clearly describe the current rotating detonation combustor with a non-circular cross-section, certain terminology will be used to refer to and describe relevant machine components within the scope of this disclosure. To the extent possible, common industry terminology will be used and employed in a manner consistent with the accepted meaning of the terms. Unless otherwise stated, such terminology should be given a broad interpretation consistent with the context of the present application and the scope of the appended claims. Those of ordinary skill in the art will appreciate that often a particular component may be referred to using several different or overlapping terms. What may be described herein as being a single part may include and be referenced in another context as consisting of multiple components. Alternatively, what may be described herein as including multiple components may be referred to elsewhere as a single integrated part.
In addition, several descriptive terms may be used regularly herein, as described below. The terms “first”, “second”, and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components.
As used herein, “downstream” and “upstream” are terms that indicate a direction relative to the flow of a fluid, such as the working fluid through the turbine engine. The term “downstream” corresponds to the direction of flow of the fluid, and the term “upstream” refers to the direction opposite to the flow (i.e., the direction from which the fluid flows). The terms “forward” and “aft,” without any further specificity, refer to relative position, with “forward” being used to describe components or surfaces located toward the front (or compressor) end of the engine or toward the inlet end of the combustor, and “aft” being used to describe components located toward the rearward (or turbine) end of the engine or toward the outlet end of the combustor. The term “inner” is used to describe components in proximity to the turbine shaft or longitudinal axis of the combustor, while the term “outer” is used to describe components distal to the turbine shaft or longitudinal axis of the combustor.
It is often required to describe parts that are at differing radial, axial and/or circumferential positions. As shown in
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
Each example is provided by way of explanation, not limitation. In fact, it will be apparent to those skilled in the art that modifications and variations can be made without departing from the scope or spirit thereof. For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present disclosure covers such modifications and variations as come within the scope of the appended claims and their equivalents.
Although exemplary embodiments of the present disclosure will be described generally in the context of rotating detonation combustors for use in aircraft propulsion for purposes of illustration, one of ordinary skill in the art will readily appreciate that embodiments of the present disclosure may be applied to land-based power-generating gas turbines as well.
Referring now to the drawings,
In the present embodiments, the annular passage (e.g., 104) is symmetrical about a centerline 105, or longitudinal axis, of the combustor 100, which may be co-linear with the engine centerline. In this context, the term “annular” is not limited to a passage defining a circular cross-section. Rather, the term “annular” broadly encompasses any unobstructed passage of any shape that circumferentially surrounds the centerline 105 and that defines a passage through which a fluid (e.g., combustion products) may flow.
The inlet end 110 of the combustor 100 includes a forward wall 114, while the outlet end 120 includes an aft wall 124. The forward wall 114 defines the upstream boundary of the annular passage 104, while the aft wall 124 defines the downstream boundary of the annular passage 104.
A plenum 130 is fluidly coupled to the combustor tube 102 upstream of a fluid inlet 132 for delivering air, oxidizer, or other fluids to the annular passage 104. In the illustrated embodiment, the plenum 130 is an air plenum, which receives air from an air supply (such as a compressor, not shown). However, the plenum 130 may instead deliver a mixture of fuel and air into the annular passage 104.
The plenum 130 is defined within a first sidewall 134 (that defines a radially outer boundary of the plenum 130), a second sidewall 136 (that defines a radially inner boundary of the plenum 130), and a plenum end wall 137 (that defines an axially aft boundary of the plenum 130). Each of the first and second sidewalls 134, 136 extend in an axial, or substantially axial, direction. A curved transition portion 135 extends between the first sidewall 134 and the forward wall 114 of the combustor tube 102. The plenum end wall 137 extends between the second sidewall 136 and the inner wall 106 of the combustor tube 102. Specifically, the plenum end wall 137 defines a curved surface extending from the second sidewall 136, which includes a concave portion that opens in the direction of fluid flow into the plenum 130. The curved surface of the plenum end wall 136 forms a generally radial transition to the fluid inlet 132 at the inlet end 110 of the combustor tube 102.
Fuel injectors 140 may be disposed in a circumferential array through the forward wall 114 positioned at a radial location corresponding to the fluid inlet 132. The fuel injectors 140 may be disposed in the forward wall 114 that is axially forward of the inner wall 106. The fuel injectors 140 disperse fuel from a fuel supply 144, via fuel inlets 142, into the inlet air, as the inlet air flows in a radially outward direction through the fluid inlet 132 and into the combustor annular passage 104.
In the illustrated embodiment, the fuel inlets 142 disperse fuel in an axial direction, orthogonal to the direction of flow of the inlet air, which flows into the annulus 104 in a radially outward direction. A fuel line 146 fluidly couples the fuel supply 144 to the one or more fuel injectors 140 for deliver fuel to the one or more fuel injectors 140. A first fuel control valve 148 is fluidly coupled to the fuel line 146.
A fuel/oxidizer mixture 212 enters an inlet end 210 of the combustor 200 and is ignited. In this configuration, a detonation wave 218 originating from a detonation front 216 travels in a continuously curving path through the elliptical annular passage 204 to an outlet end 220, where the combustion products 222 exit the combustor tube 202. The outlet end 220 defines an elliptical annular passage in fluid communication with the elliptical annular passage 204.
Although the fuel/oxidizer mixture 212 is shown entering the inlet end 210 in an axial direction, it should be understood that the fuel/oxidizer mixture 212 may enter the inlet end 210 in a radial direction; that the fuel may be introduced in an axial direction through one or more fuel inlets, while the oxidizer (e.g., air) is introduced in a radial direction through one or more air inlets; or that the oxidizer (e.g., air) may be introduced in an axial direction through one or more air inlets, while the fuel is introduced in a radial direction through one or more fuel inlets.
Specifically, the combustor tube 302 includes an inner wall 306 and an outer wall 308. The inner wall 306 has a first straight side 332, a second straight side 336 opposite and parallel to the first straight side 332, a first curved segment 334 connecting a first end of the first straight side 332 to a corresponding first end of the second straight side 336, and a second curved segment 338 connecting a second end of the first straight side 332 to a corresponding second end of the second straight side 336. The outer wall 308 is similarly constructed with a first straight side 342, a first curved segment 344 extending from a first end of the first straight side 342, a second straight side 346 opposite and parallel to the first straight side 342 and connected to the first curved segment at a first end, and a second curved segment 348 extending from a second end of the second straight side 346 to a second end of the first straight side 342.
The respective racetrack shapes defined by the inner wall 306 and the outer wall 308 are disposed in concentric relationship around a longitudinal axis, or centerline, 305 of the combustor 300 to define a racetrack-shaped annular passage 304 between the inner wall 306 and the outer wall 308. The inner wall 306 and the outer wall 308 are connected at an inlet end 310 of the combustor 300 by a forward wall 314 (shown in
In the exemplary configuration shown in
The fuel/oxidizer mixture 312 enters an inlet end 310 of the combustor 300 and is ignited. In this configuration, a detonation wave 318 originating from a detonation front 316 travels in a continuously curving path through the racetrack-shaped annular passage 304 to an outlet end 320, where the combustion products 322 exit the combustor tube 302 (as in
Although the fuel/oxidizer mixture 312 is shown entering the inlet end 310 in a radial direction, it should be understood that the fuel/oxidizer mixture 312 may enter the inlet end 310 in an axial direction; that the fuel may be introduced in an axial direction through one or more fuel inlets, while the oxidizer (e.g., air) is introduced in a radial direction through one or more air inlets; or that the oxidizer (e.g., air) may be introduced in an axial direction through one or more air inlets, while the fuel is introduced in a radial direction through one or more fuel inlets.
Specifically, the combustor tube 402 includes an inner wall 406 and an outer wall 408. The inner wall 406 includes, in series, a first straight side 432, a first arcuate corner segment 433, a second straight side 434, a second arcuate corner segment 435, a third straight segment 436, and a third arcuate corner segment 437. The outer wall 408 is similarly constructed with a first straight side 442, a first arcuate corner segment 443, a second straight side 444, a second arcuate corner segment 445, a third straight segment 446, and a third arcuate corner segment 447, in series.
The respective triangular shapes defined by the inner wall 406 and the outer wall 408 are disposed in concentric relationship around a longitudinal axis, or centerline, 405 of the combustor 400 to define a triangular-shaped annular passage 404 between the inner wall 406 and the outer wall 408. The inner wall 406 and the outer wall 408 are connected at an inlet end 410 of the combustor 400 by a forward wall 414 (shown in
In the exemplary configuration shown in
The fuel/oxidizer mixture 412 enters an inlet end 410 of the combustor 400 and is ignited. In this configuration, a detonation wave 418 originating from a detonation front 416 travels in a continuously curving path through the triangular-shaped annular passage 404 to an outlet end 420, where the combustion products 422 exit the combustor tube 402 (as in
Although the fuel/oxidizer mixture 412 is shown entering the inlet end 410 in a radial direction, it should be understood that the fuel/oxidizer mixture 412 may enter the inlet end 410 in an axial direction; that the fuel may be introduced in an axial direction through one or more fuel inlets, while the oxidizer (e.g., air) is introduced in a radial direction through one or more air inlets; or that the oxidizer (e.g., air) may be introduced in an axial direction through one or more air inlets, while the fuel is introduced in a radial direction through one or more fuel inlets.
Specifically, the combustor tube 502 includes an inner wall 506 and an outer wall 508. The inner wall 506 includes, in series, a first side 531, a first corner side 532, a second side 533, a second corner side 534, a third side 535 opposite the first side 531, a third corner side 536, a fourth side 537 opposite the second side 533, and a fourth corner side 538. The outer wall 508 is similarly constructed with a first side 541, a first corner side 542, a second side 543, a second corner side 544, a third side 545 opposite the first side 541, a third corner side 546, a fourth side 547 opposite the second side 543, and a fourth corner side 548, in series.
The respective octagonal shapes defined by the inner wall 506 and the outer wall 508 are disposed in concentric relationship around a longitudinal axis, or centerline, 505 of the combustor 500 to define an octagonal-shaped annular passage 504 between the inner wall 506 and the outer wall 508. The inner wall 506 and the outer wall 508 are connected at an inlet end 510 of the combustor 500 by a forward wall (not shown).
In the exemplary configuration shown in
The fuel/oxidizer mixture 512 enters an inlet end 510 of the combustor 500 and is ignited. In this configuration, a detonation wave 518 originating from a detonation front 516 travels in a continuously curving path through the octagonal-shaped annular passage 504 to an outlet end 520, where the combustion products 522 exit the combustor tube 502 (as in
Although the fuel/oxidizer mixture 512 is shown entering the inlet end 510 in a radial direction, it should be understood that the fuel/oxidizer mixture 512 may enter the inlet end 510 in an axial direction; that the fuel may be introduced in an axial direction through one or more fuel inlets, while the oxidizer (e.g., air) is introduced in a radial direction through one or more air inlets; or that the oxidizer (e.g., air) may be introduced in an axial direction through one or more air inlets, while the fuel is introduced in a radial direction through one or more fuel inlets.
Further, although the plenum wall 550 is defined radially inward of the inner wall 506, it should be understood that the plenum wall 550 may instead by disposed radially outward of the outer wall 508 (in which case the fuel/air mixture 512 would be introduced in a radially inward direction). Alternately, plenums 554 may be disposed both radially inward and radially outward of the combustor tube 502 (as shown in
Specifically, the combustor tube 602 includes an inner wall 606 and an outer wall 608. The inner wall 606 includes, in series, a first side 631, a first arcuate corner segment 632, a second side 633, a second arcuate corner segment 634, a third side 635 opposite the first side 631, a third arcuate corner segment 636, a fourth side 637 opposite the second side 633, and a fourth arcuate corner segment 638. The outer wall 608 is similarly constructed with a first side 641, a first arcuate corner segment 642, a second side 643, a second arcuate corner segment 644, a third side 645 opposite the first side 641, a third arcuate corner segment 646, a fourth side 647 opposite the second side 643, and a fourth arcuate corner segment 648, in series.
The respective rectangular shapes defined by the inner wall 606 and the outer wall 608 are disposed in concentric relationship around a longitudinal axis, or centerline, 605 of the combustor 600 to define a generally rectangular-shaped annular passage 604 between the inner wall 606 and the outer wall 608. The inner wall 606 and the outer wall 608 are connected at an inlet end 610 of the combustor 600 by a forward wall (not shown).
In the exemplary configuration shown in
The inlet end 610 also includes a second fluid plenum 664, which is located radially outward of the outer wall 608 and which is defined by a second plenum wall 660. The second fluid plenum 664 may direct fuel, oxidizer, or a fuel/oxidizer mixture 612 in a radial (or substantially radial) direction into the combustor 600, via inlet ports 665 defined in the first side 641, the second side 643, the third side 645, and/or the fourth side 647 of the outer wall 608. No inlet ports 665 are provided in the corner segments 642, 644, 646, and 648. For clarity, the first fluid plenum 654 and the second fluid plenum 664 are omitted from
The fuel/oxidizer mixture 612 enters an inlet end 610 of the combustor 600 and is ignited. In this configuration, a detonation wave 618 originating from a detonation front 616 travels in a continuously curving path through the generally rectangular-shaped annular passage 604 to an outlet end 620, where the combustion products 622 exit the combustor tube 602 (as in
Although the fuel/oxidizer mixture 610 is shown entering the inlet end 610 in a radial direction, it should be understood that the fuel/oxidizer mixture 612 may enter the inlet end 610 in an axial direction; that the fuel may be introduced in an axial direction through one or more fuel inlets, while the oxidizer (e.g., air) is introduced in a radial direction through one or more air inlets; or that the oxidizer (e.g., air) may be introduced in an axial direction through one or more air inlets, while the fuel is introduced in a radial direction through one or more fuel inlets; or that the fuel may be introduced from one fluid plenum, while the oxidizer is introduced from the other fluid plenum. Further, although two plenums 654, 664 are illustrated, it should be understood that a single plenum (654 or 664) defined by a single plenum wall (650, 660, respectively) may instead be used.
Although the fluid plenums illustrated herein define a continuous annulus radially inward or radially outward of a respective combustor wall, it should be understood that the fluid plenums may be divided into two or more sub-plenums, if desired.
By providing the rotating detonation combustor with a non-circular cross-sectional annulus, the ability to direct the combustion gases into a turbine section of a gas turbine is significantly enhanced. The non-circular cross-sectional annulus may be elliptical or polygonal with the annulus being defined between inner and outer walls having curved sides or a combination of curved and straight sides. In those embodiments in which the inner and outer walls have both curved and straight sides, the fuel/air mixture is introduced through one or more fluid inlets defined through one or more of the straight sides.
Exemplary embodiments of the rotating detonation combustor with non-circular cross-section are described above in detail. The rotating detonation combustors described herein are not limited to the specific embodiments described herein, but rather, components of the rotating detonation combustor may be utilized independently and separately from other components described herein.
While the technical advancements have been described in terms of various specific embodiments, those skilled in the art will recognize that the technical advancements can be practiced with modification within the spirit and scope of the claims.