Rotary detonation combustion chamber with accurate and controllable detonation wave propagation direction

Abstract

A rotary detonation combustion chamber with accurately controllable detonation wave propagation direction includes an intake duct, a fuel system assembly, an igniter, and a detonation combustion chamber. The fuel system assembly is connected to the intake duct and supplies fuel to the detonation combustion chamber. The igniter is located at the front end of the detonation combustion chamber and ignites the fuel-air mixture entering the chamber to form rotary detonation combustion. A deflecting wedge is located within the combustion chamber, with an angle of 45° to the horizontal. The wedge includes film cooling holes and cooling channels. The film cooling holes penetrate the wedge along its thickness, and the cooling channels are arranged along its width, communicating internally with the film cooling holes. This invention is simple in principle and reliable in structure, enabling accurate control of the detonation wave propagation direction during the operation of the rotary detonation combustion chamber, thereby achieving optimal matching between the rotary detonation combustion chamber and turbine components.

Description

Technical Field

[0001] This invention relates to the field of rotary detonation engines, and more particularly to a rotary detonation combustion chamber with accurate and controllable detonation wave propagation direction. Background Technology

[0002] Combustion can be divided into two different modes: detonation and knock. Compared to detonation, knock not only has higher thermal efficiency and energy release rate, but also achieves total pressure gain. By replacing the detonation combustor in a traditional aero-engine with a knock combustor, it is expected to further improve the engine's overall performance. Currently, there are three main types of knock combustors: pulse knock combustors, oblique knock combustors, and rotating knock combustors. Among them, rotating knock combustors have the characteristics of compact structure, stable thrust, and continuous operation with only one ignition, and are expected to be the first to achieve practical engineering applications.

[0003] Combining with a gas turbine engine to form a rotating detonation gas turbine engine is one of the technological applications of rotating detonation combustion chambers. Compared with traditional gas turbine engines, rotating detonation gas turbine engines can reduce the number of compressor stages, simplify the engine structure, and reduce engine weight. At the same time, rotating detonation gas turbine engines also have the advantages of low fuel consumption and high thrust-to-weight ratio [1]. However, the gas at the outlet of the rotating detonation combustion chamber is in a high-frequency pulsating state. This pulsating characteristic will affect the stability of turbine output power, increase the aerodynamic load on the blades, and reduce the service life and reliability of the turbine. Moreover, the propagation direction of the detonation wave will affect the occurrence of the above phenomena [2]. Experimental results show that during the propagation of rotating detonation combustion waves, multiple propagation modes may occur, including clockwise propagation mode, counterclockwise propagation mode, and multi-wave reverse collision mode [3]. This uncertainty in the propagation direction of the detonation wave is very unfavorable for the stable operation of the turbine. Therefore, achieving control over the propagation direction of the detonation wave is of great significance for promoting the technological development of rotating detonation gas turbine engines.

[0004] References

[0005] [1]Zhou S,Ma H,Ma Y,et al.Experimental investigation on detonationwave propagation mode in the start-up process of rotating detonation turbineengine[J].Aerospace Science and Technology,2021,111:106559.

[0006] [2]W.Wei,Y.Wu,C.Weng,Q.Zheng,Influence of Propagation Direction onOperation Per-formance of Rotating Detonation Combustor with Turbine GuideVane,Defence Technology,2020.

[0007] [3]Meng H, Zheng Q, Weng C, Wu Y, Feng W, Xu G, et al. Propagation modeanalysis of rotating detonation waves fueled by liquid kerosene. ActaAstronaut 2021; 187:248–258. https: / / doi.org / 10.1016 / j.actaastro.2021.06.043. Summary of the Invention

[0008] The purpose of this invention is to solve the above-mentioned problems in the prior art and provide a rotary detonation combustion chamber with accurate and controllable detonation wave propagation direction. The principle is simple and the structure is reliable. It can accurately control the detonation wave propagation direction during the operation of the rotary detonation combustion chamber, thereby achieving optimal matching between the rotary detonation combustion chamber and the turbine components.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A rotary detonation combustion chamber with accurate and controllable detonation wave propagation direction, including an intake manifold, fuel system components, igniter, and detonation combustion chamber;

[0011] The oil circuit assembly is connected to the air intake and is used to supply fuel to the detonation combustion chamber;

[0012] The igniter is located at the front end of the detonation combustion chamber and is used to ignite the fuel-air mixture entering the detonation combustion chamber to form rotary detonation combustion.

[0013] The detonation combustion chamber is located behind the air intake and includes an inner wall, an outer wall, and a deflecting wedge. The inner and outer wall form a cavity, and the deflecting wedge is located inside the cavity and installed on the inner wall. The angle between the deflecting wedge and the horizontal direction is 45°. The deflecting wedge includes film cooling holes and cooling channels. The film cooling holes penetrate the deflecting wedge along its thickness direction, and the cooling channels are arranged along the width direction of the deflecting wedge. The cooling channels and film cooling holes are internally connected, and the outer end of the cooling channels is connected to the outside. Cooling gas is injected into the deflecting wedge through the cooling channels and then flows out through the film cooling holes.

[0014] The oil circuit assembly includes an oil supply line and an atomizing nozzle located at the end of the oil supply line, wherein the atomizing nozzle is located inside the air intake.

[0015] The oil circuit components are arranged in multiple sets evenly along the circumference of the engine.

[0016] The igniters are evenly arranged around the circumference of the engine.

[0017] The deflection wedges are evenly arranged around the circumference of the detonation combustion chamber.

[0018] Compared with the prior art, the beneficial effects achieved by the technical solution of this invention are:

[0019] The rotary detonation combustion chamber of the present invention, which has accurate and controllable detonation wave propagation direction, can automatically achieve accurate control of the detonation wave propagation direction during the operation of the rotary detonation combustion chamber by utilizing the interaction between the deflection wedge plate and the detonation wave-induced oblique shock wave. Its principle is simple and its structure is reliable. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the present invention.

[0021] Figure 2 This is a cross-sectional schematic diagram of the present invention.

[0022] Figure 3 This is a schematic diagram of the oil circuit components.

[0023] Figure 4 This is a schematic diagram of the deflection wedge.

[0024] Figure 5 This is a schematic diagram illustrating how a deflection wedge controls the propagation direction of a detonation wave.

[0025] Reference numerals: 1. Intake duct; 2. Oil circuit assembly; 21. Oil supply line; 22. Atomizing nozzle; 3. Ignition device; 4. Detonation combustion chamber; 41. Inner wall surface; 42. Outer wall surface; 43. Deflection wedge plate; 431. Film cooling hole; 432. Cooling channel. Detailed Implementation

[0026] To make the technical problems, technical solutions and beneficial effects of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0027] See Figures 1-4 The rotary detonation combustion chamber with accurate and controllable detonation wave propagation direction described in this invention includes an air intake duct 1, an oil circuit assembly 2, an igniter 3, and a detonation combustion chamber 4.

[0028] The detonation combustion chamber 4 is located behind the intake duct 1 and includes an inner wall surface 41, an outer wall surface 42, and a deflection wedge plate 43. The inner wall surface 41 and the outer wall surface 42 form a cavity. The deflection wedge plate 43 is located inside the cavity and installed on the inner wall surface 41. The angle between the deflection wedge plate 43 and the horizontal direction is 45°. The deflection wedge plate 43 includes a film cooling hole 431 and a cooling channel 432. The film cooling hole 431 penetrates the deflection wedge plate 43 along the thickness direction. The cooling channel 432 is arranged along the width direction of the deflection wedge plate 43, and the cooling channel 432 communicates internally with the film cooling hole 431. The outer end of the cooling channel 432 communicates with the outside. Cooling gas is injected into the deflection wedge plate 43 through the cooling channel 432, and then the cooling gas flows out from a plurality of film cooling holes 431 evenly distributed on the surface of the deflection wedge plate 43.

[0029] The fuel circuit assembly 2 is controlled to be connected to the intake duct 1 and is used to supply fuel to the detonation combustion chamber 4. It includes a fuel supply line 21 and an atomizing nozzle 22 located at the end of the fuel supply line 21. The atomizing nozzle 22 is located inside the intake duct 1.

[0030] The igniter 3 is located at the front end of the detonation combustion chamber 4 and is used to ignite the fuel-air mixture entering the detonation combustion chamber 4 to form a rotating detonation combustion.

[0031] In this embodiment, 12 sets of fuel circuit components 2 are evenly distributed along the circumference of the engine, and 8 sets of igniters 3 are evenly distributed along the circumference of the engine to facilitate the smooth initiation and stable combustion of the detonation combustion chamber 4. Fuel is supplied through the fuel supply line 21 and atomized by the atomizing nozzle 22, then mixed with the incoming air in the intake manifold 1. After mixing, the fuel flows into the detonation combustion chamber 4 and is ignited by the igniter 3 to form rotating detonation combustion.

[0032] In this embodiment, eight deflection wedges are evenly distributed around the circumference, and each deflection wedge has a plurality of air film cooling holes 431 evenly distributed. Specifically, the bottom of the deflection wedge is provided with mounting holes, through which the deflection wedge is mounted to the inner wall surface.

[0033] While detonation combustion is taking place in the rotating detonation combustion chamber 4, cooling gas is introduced from the outside and injected into the deflection wedge plate 43 through the cooling channel 432. Then, the cooling gas flows out through the gas film cooling hole 431, which isolates the high-temperature combustion gas from direct contact with the deflection wedge plate 43, thereby achieving the purpose of thermal protection.

[0034] Reference Figure 5 The deflection wedge in the rotating detonation combustion chamber of the present invention, which allows for precise control of the detonation wave propagation direction, can accurately control the propagation direction of the detonation wave. The control process is as follows:

[0035] 1. When the detonation wave propagates counterclockwise, the simulation results obtained by Fluent software are as follows: Figure 5 As shown in (a), at this time, the oblique shock wave induced by the detonation wave is in a relatively "perpendicular" state with the deflection wedge. The oblique shock wave will only undergo slight shock wave reflection at the deflection wedge. The weak reflected wave generated will not have a significant impact on the detonation combustion state.

[0036] 2. When the detonation wave propagates clockwise, the simulation results are as follows: Figure 5 As shown in (b), the oblique shock wave induced by the detonation wave is in a relatively "parallel" state with the deflection wedge, and the oblique shock wave will be strongly reflected on the surface of the deflection wedge. When this high-intensity reflected shock wave returns to the detonation wave, it will significantly inhibit the injection of fresh premixed gas, causing the height of the premixed gas filling area to decrease;

[0037] 3. In the next propagation cycle, because the premixed zone height is too low to sustain the continued propagation of the detonation wave, the detonation wave is annihilated, and the rotating detonation combustion chamber enters the detonation period. Only after the next ignition generates a rotating detonation wave with the opposite propagation direction can the combustion chamber enter a stable operating state, thereby achieving accurate control of the detonation wave propagation direction.

[0038] The rotary detonation combustion chamber of the present invention provides for accurate and controllable detonation wave propagation direction. It can accurately control the propagation direction of detonation waves during the operation of the rotary detonation combustion chamber. Furthermore, it has a simple principle, reliable structure, and is easy to apply in engineering practice.

Claims

1. A rotating detonation combustion chamber with accurate and controllable detonation wave propagation direction, characterized in that: This includes the air intake, fuel system components, igniter, and knock combustion chamber; The oil circuit assembly is connected to the air intake and is used to supply fuel to the detonation combustion chamber; The igniter is located at the front end of the detonation combustion chamber and is used to ignite the fuel-air mixture entering the detonation combustion chamber to form rotary detonation combustion. The detonation combustion chamber is located behind the air intake and includes an inner wall, an outer wall, and a deflecting wedge. The inner and outer wall form a cavity, and the deflecting wedge is located inside the cavity and installed on the inner wall. The angle between the deflecting wedge and the horizontal direction is 45°. The deflecting wedge includes film cooling holes and cooling channels. The film cooling holes penetrate the deflecting wedge along its thickness direction, and the cooling channels are arranged along the width direction of the deflecting wedge. The cooling channels and film cooling holes are internally connected, and the outer end of the cooling channels is connected to the outside. Cooling gas is injected into the deflecting wedge through the cooling channels and then flows out through the film cooling holes.

2. The rotating detonation combustion chamber with accurately controllable detonation wave propagation direction as described in claim 1, characterized in that: The oil circuit assembly includes an oil supply line and an atomizing nozzle located at the end of the oil supply line, wherein the atomizing nozzle is located inside the air intake.

3. The rotating detonation combustion chamber with accurately controllable detonation wave propagation direction as described in claim 1, characterized in that: The oil circuit components are arranged in multiple sets evenly along the circumference of the engine.

4. The rotating detonation combustion chamber with accurately controllable detonation wave propagation direction as described in claim 1, characterized in that: The igniters are evenly arranged around the circumference of the engine.

5. The rotating detonation combustion chamber with accurately controllable detonation wave propagation direction as described in claim 1, characterized in that: The deflection wedges are evenly arranged around the circumference of the detonation combustion chamber.

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