A rotating detonation turbine engine device

Abstract

The present invention discloses a rotary detonation turbine engine device, comprising a centrifugal compressor, a compressor casing, a diffuser buffer chamber, a fuel end cover, a fuel gas collecting chamber, a combustion chamber body, a guide vane, an axial-flow turbine, and a lubrication and cooling device. A starting motor is arranged at the compressor head, which drives the turbine-compressor shaft to rotate at high speed through a coupling. The high-speed rotating compressor compresses the outside air and passes through the diffuser buffer chamber, further accelerating it and entering the combustion chamber through an annular gap. The fuel is injected into the combustion chamber through small holes evenly distributed around the circumference. The air and fuel are mixed, ignited and detonated to form a detonation wave. The detonation wave continuously rotates and propagates in the annular combustion chamber and is discharged at high speed. The discharged working fluid passes through the turbine guide and impacts the turbine to rotate at high speed. The turbine drives the compressor to rotate at high speed and continue to compress the outside air into the combustion chamber. This cycle is repeated to achieve continuous and stable operation of the rotary detonation turbine engine.

Description

Technical Field

[0001] The invention belongs to the technical field of engines, in particular to a rotary detonation turbine engine. Background Art

[0002] Although rotating detonation engines have many performance advantages such as high thermal cycle efficiency, large specific impulse, high thrust-to-weight ratio, and wide operating range, their mechanical power extraction efficiency is not very high compared to gas turbine engines. Therefore, there is still much room for innovation and improvement in existing rotating detonation engines.

[0003] The rotating detonation turbine engine is a new type of engine, developed based on the rotating detonation engine. It combines the advantages of detonation combustion, such as high efficiency and self-supercharging, with the convenient mechanical power extraction of traditional turbojet engines to improve the propulsion performance of existing power plants. It replaces the combustion chamber of a gas turbine engine with a rotating detonation combustor, achieving a transition from an isobaric cycle to a detonation cycle, improving engine propulsion performance and fuel utilization. Because the intake and exhaust processes of a rotating detonation combustor are essentially steady-state, the pressure pulsation is smaller than that of a pulse detonation engine. Therefore, combining the rotating detonation combustor with a compressor and turbine reduces the impact of the pressure pulsation caused by the detonation wave on the compressor and turbine, achieving a breakthrough in power plant performance and adaptability while reducing costs. The rotating detonation turbine engine combines the advantages of the high thermal cycle efficiency of detonation combustion with the high mechanical power extraction efficiency of a turbojet engine, and therefore has the potential to bring about a leap forward in aerospace propulsion technology.

[0004] As a combined engine, the rotating detonation turbine engine has a relatively complex structure and many technical difficulties. Since the compressor compresses the external air through the blades, the flow field is uneven and the intake air will have flow distortion. The flow distortion will have a great impact on the working performance of the rotating detonation combustion chamber and make the detonation combustion unstable. In addition, due to the high-speed rotation propagation of the detonation wave, the motion return shock wave generated upstream of the combustion chamber will also affect the normal operation of the compressor. The development of a device to suppress the forward transmission of the motion shock wave is an important prerequisite for achieving the matching of the rotating detonation combustion chamber and the compressor. Since the exhaust gas at the outlet of the rotating detonation combustion chamber passes through the guide device and then impacts the turbine, the periodic strong intermittent shock wave has a significant impact on the working efficiency and life of the turbine. Therefore, the uniformity of the flow field at the outlet of the rotating detonation combustion chamber is the key to the matching of the rotating detonation combustion chamber and the turbine. Summary of the Invention

[0005] The purpose of the present invention is to provide a rotating detonation turbine engine to better achieve the matching of the rotating detonation combustion chamber with the compressor and the turbine, and to successfully achieve the start, operation and stop of the engine.

[0006] The technical solutions for achieving the purpose of the present invention are:

[0007] A rotating detonation turbine engine comprises a combustion chamber, an ignition hole and a fuel injection hole arranged on the combustion chamber, and is characterized in that:

[0008] The combustion chamber is an annular combustion chamber consisting of a combustion chamber outer shell and a combustion chamber inner shell;

[0009] A shaft sleeve is provided in the combustion chamber casing, and the shaft sleeve rotatably supports the turbine-compressor shaft;

[0010] The front and rear ends of the turbine-compressor shaft are respectively fixed with a centrifugal compressor and an axial-flow turbine; the centrifugal compressor is used to compress external air into the combustion chamber;

[0011] The front and rear ends of the combustion chamber casing are respectively fixed with a compressor casing and a turbine casing;

[0012] A pressure diffuser buffer chamber is provided between the compressor casing and the combustion chamber inner casing, for accelerating and rectifying the incoming air into the combustion chamber and suppressing the forward propagation of the movement shock wave of the combustion chamber; an air injection annular gap is provided between the pressure diffuser buffer chamber and the front section of the annular combustion chamber;

[0013] A fuel collecting chamber is provided between the compressor casing and the combustion chamber casing. A plurality of fuel injection holes are evenly arranged around the fuel collecting chamber, and the fuel injection holes are located in the front section of the annular combustion chamber, for injecting fuel and mixing it with air; the ignition hole is located in the middle section of the annular combustion chamber, for igniting the mixed fuel and forming a rotating detonation wave; the detonation products drive the turbine to rotate, and the turbine shaft drives the compressor to rotate at high speed, thereby realizing the self-priming function of the compressor.

[0014] Compared with the prior art, the present invention has the following significant advantages:

[0015] (1) The present invention adopts an axial-flow turbine-compressor rotor assembly, and the rotor shaft passes through a rotating detonation annular combustion chamber. The combustion chamber and the rotor assembly do not interfere with each other, can work in coordination, and have good matching. The turbine does not directly affect the combustion conditions in the main combustion chamber during high-speed rotation.

[0016] (2) The present invention adopts an annular rotating detonation combustion chamber, which has the characteristics of simple structure and high compatibility with the turbine and compressor. In addition, the rotating detonation combustion chamber is coaxial with the rotor assembly, and the rotor shaft, cooling and lubricating oil circuit and other devices are installed in the inner cavity of the annular inner wall, which effectively improves the space utilization of the engine, makes the engine structure more compact and highly integrated.

[0017] (3) During operation, the engine of the present invention operates in the form of detonation combustion in the annular combustion chamber, which is close to isochoric combustion. Compared with the isobaric combustion mode of the traditional turbine engine, it has the advantages of high thermal efficiency, short reaction zone, and self-pressurization. Therefore, it effectively shortens the length of the combustion chamber and improves the working efficiency of the combustion chamber, which is beneficial to improving the engine thrust-to-weight ratio.

[0018] (4) During operation, the engine of the present invention has the characteristic of self-priming due to the compression of external air by the compressor, so no separate air supply device is required, thereby greatly simplifying the external devices.

[0019] (5) During operation, the continuous high-speed rotational propagation of the detonation wave in the engine of the present invention affects the stable operation of the compressor upstream of the combustion chamber. Adding a pressure diffuser buffer chamber component between the combustion chamber and the compressor can rectify the incoming air entering the combustion chamber through the compressor and effectively suppress the forward propagation of the high-frequency pressure disturbance of the detonation combustion chamber, thereby facilitating efficient matching of the rotating detonation combustion chamber and the compressor.

[0020] (6) During operation, the flow field at the outlet of the rotating detonation combustion chamber of the present invention exhibits circumferential non-uniformity, which affects the efficiency of rotating components such as the turbine downstream of the combustion chamber. A turbine guide is installed between the combustion chamber and the turbine to rectify the working fluid discharged from the combustion chamber outlet, reduce the amplitude of high-frequency pressure oscillations at the outlet, and improve the compatibility between the rotating detonation combustion chamber and the turbine.

[0021] (7) The engine of the present invention employs a cooling and lubricating device. An electric pump can supply external lubricating oil to the shaft sleeve, circulating the oil and providing cooling and lubrication. This ensures the life of the shaft and bearings, thereby ensuring long-term engine operation and greatly improving repeatability. The cooling oil pipe is arranged in the cavity inside the inner wall of the annular combustion chamber, improving the space utilization of the engine and reducing the complexity of external equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic structural diagram of the rotating detonation turbine engine of the present invention.

[0023] Figure 2 It is a schematic structural diagram of the air flow path when the rotary detonation turbine engine of the present invention is working.

[0024] Figure 3 It is a gas state process diagram of the air flow channel when the rotary detonation turbine engine of the present invention is working.

[0025] In the figure, 1- compressor casing, 2- air injection annular gap, 3- fuel injection hole, 4- fuel collecting cavity front cover, 5- fuel inlet, 6- combustion chamber casing, 7- combustion chamber inner casing, 8- annular combustion chamber, 9- oil pipe, 10- turbine casing, 11- turbine locking nut, 12- axial-flow turbine, 13- turbine guide vane, 14- bushing, 15- turbine-compressor shaft, 16- ignition hole, 17- fuel collecting cavity, 18- diffuser buffer cavity, 19- centrifugal compressor, 20- compressor locking nut. DETAILED DESCRIPTION

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0027] Combine Figure 1 A rotating detonation turbine engine of this embodiment includes a compressor casing 1, an air injection annular seam 2, a fuel injection hole 3, a fuel collecting chamber front cover 4 and a fuel inlet 5 at the engine head, an annular combustion chamber 8 composed of a combustion chamber casing 6 and a combustion chamber inner casing 7, an oil pipe 9 for providing lubricating oil to the engine, a turbine casing 10 at the tail of the engine, an axial-flow turbine 12, a turbine locking nut 11, a turbine guide 13, a shaft sleeve 14, a turbine-compressor shaft 15 passing through the combustion chamber, an ignition hole 16 for engine ignition, a fuel collecting chamber 17, a diffuser buffer chamber 18, a centrifugal compressor 19 and a compressor locking nut 20.

[0028] A shaft sleeve 14 is provided in the center of the combustion chamber inner shell 7, and the turbine-compressor shaft 15 is arranged in the shaft sleeve 14, and both ends are supported in the shaft sleeve 14 by bearings. The turbine-compressor shaft 15 of the rotor assembly coincides with the central axis of the rotating detonation main combustion chamber; the front and rear ends of the turbine-compressor shaft 15 are respectively provided with a centrifugal compressor 19 and an axial-flow turbine 12, and the centrifugal compressor 19 and the axial-flow turbine 12 are respectively locked by a compressor locking nut 20 and a turbine locking nut 11; the compressor The housing 1 is fixed to the front end of the combustion chamber housing 6, and the turbine housing 10 is fixed to the rear end of the combustion chamber housing 6. A turbine guide 13 is provided at the rear end of the combustion chamber inner housing 7. Multiple fuel inlets 5 are evenly distributed along the circumference of the combustion chamber housing 6, and the fuel inlets 5 are located at the front end of the annular combustion chamber 8. The combustion chamber housing 6 also has an ignition hole 16 located in the middle section of the annular combustion chamber 8. The ignition hole 16 is threaded and can be connected to various ignition devices, such as low-energy spark plugs, high-energy ignition plugs, and pre-detonation tubes. The fuel inlet 5 is located on the fuel manifold front cover 4 outside the fuel manifold 17 and is used to inject fuel into the fuel manifold 17. The fuel is then injected into the front end of the annular combustion chamber 8 through multiple fuel injection holes 3 evenly distributed along the circumference. An air injection annular gap 2 is provided between the diffuser buffer chamber 18 and the front end of the annular combustion chamber 8. Air is injected through the air injection annular gap 2 at the front end of the combustion chamber.

[0029] In order to start the engine, a starting motor is installed at the compressor head, which drives the turbine-compressor shaft to rotate at high speed through the coupling. The high-speed rotating compressor compresses the external air and flows steadily through the expansion buffer chamber, and further injects it into the rotating detonation combustion chamber through the air injection annular gap; at the same time, the fuel is injected into the combustion chamber through the fuel injection holes evenly distributed around the circumference. The air and fuel are evenly mixed, ignited by the ignition device, and detonated to form a detonation wave. The detonation wave continuously rotates and propagates in the annular combustion chamber, and the combustion products expand and accelerate along the circumferential and axial directions, and are discharged at high speed from the combustion chamber outlet. The discharged working fluid is rectified by the turbine guide vane, and then impacts the axial flow turbine to rotate at high speed. Since the turbine and compressor are coaxial, the compressor is driven by the turbine to rotate at high speed and continue to compress the external air into the combustion chamber, and this cycle is repeated.

[0030] Before the rotating detonation turbine engine operates, the starting motor drives the turbine-compressor shaft 15 to rotate at high speed. The high-speed compressor 19 compresses the ambient air, which passes through the diffuser buffer chamber 18 and is further accelerated through the air injection annular gap 2 into the annular combustion chamber 8. Simultaneously, fuel is injected into the fuel collecting chamber through the fuel inlet 5. The fuel is then injected into the annular combustion chamber 8 through the circumferentially distributed fuel injection holes 3, where the air and fuel are evenly mixed. Once mixed, the igniter installed in the ignition hole 16 begins to ignite, and the ignited mixture rapidly forms a rotating detonation wave in the combustion chamber. This rotating detonation turbine engine device can implement three ignition modes, depending on the type of fuel and the difficulty of ignition: low-energy spark plug ignition, high-energy spark plug ignition, and pre-detonation tube ignition. The resulting detonation wave continuously rotates and propagates within the annular combustion chamber. The resulting detonation products are rectified by the turbine guide vane 13 at the rear of the combustion chamber before impacting the axial-flow turbine 12. Turbine 12 generates power, which in turn drives compressor 19 to generate power. Compressor 19 then draws air into annular combustion chamber 8, at which point the starter motor stops, and the engine completes its cyclical operation. This engine assembly uses an electric pump to cool and lubricate the shaft and bearings. Lubricating oil, under pressure from the electric pump, flows through oil pipe 9 into sleeve 14. The oil collected in sleeve 14 flows to the bearings at both ends of the shaft, thereby cooling and lubricating shaft 15 and the bearings.

[0031] Figure 2A schematic diagram of the airflow path of a rotating detonation turbine engine during operation, including the incoming air inlet a, transition section b, diffuser buffer section c, air annular injection structure d, fuel orifice injection structure e, combustion chamber (front section f1, middle section f2, convergent transition section f3), combustion chamber outlet g, guide vanes h, and turbine blades i. The engine airflow direction is shown from left to right. During engine startup, the compressor rotates at high speed at the engine inlet, drawing in and compressing air. After passing through transition section b and diffuser buffer section c, the incoming air is injected into the combustion chamber by the air annular injection structure d. Simultaneously, a constant flow of fuel is injected through the fuel orifice injection structure e. After collision, the fuel and air are mixed in the front section f1 of the combustion chamber. The evenly mixed fuel is ignited and burned by the ignition device, forming a rotating detonation wave. This wave continuously rotates and propagates in the middle section f2 of the combustion chamber. Then, through the convergent transition section f3 of the combustion chamber, the periodically oscillating detonation products are discharged at high speed. The guide vanes h guide the airflow in a certain direction and impact the turbine blades i, driving the turbine to rotate at high speed. After passing through the turbine, the high-temperature, high-pressure, and high-velocity detonation products rapidly decay and are discharged, generating thrust. Because the turbine and compressor are coaxial, the high-speed rotation of the turbine shaft drives the high-speed rotation of the compressor. At this point, the compressor has the ability to perform external work and is self-priming, drawing ambient air into the combustion chamber and compressing it. This rotating detonation turbine engine achieves continuous operation.

[0032] Figure 3 This is a diagram of the gas state process in the air flow path when the rotating detonation turbine engine is working.

[0033] AB is the air intake process. When the compressor rotates at high speed, it compresses the outside air. Under the action of the compressor blades, the outside air is sucked in and compressed.

[0034] BC is the buffer expansion process. In this process, the air expands and accelerates further. The air pressure will decrease to a certain extent, while the speed will increase.

[0035] CD stands for the process of separate injection and rapid mixing of fuel and oxidizer. This rotating detonation turbine engine utilizes an annular gap-orifice injection structure, which significantly improves fuel and oxidizer mixing efficiency. This creates favorable conditions for successful engine ignition and the generation of a detonation wave.

[0036] DE is the process of the formation and continuous propagation of the rotating detonation wave. After successful ignition, a stable rotating detonation wave is formed and continuously rotates and propagates in the annular combustion chamber.

[0037] EF is the continuous propagation of the rotating detonation wave in the convergent transition section. Due to the limitation of the turbine diameter, to ensure that the detonation products more favorably impact the turbine, a convergent transition section is connected between the detonation combustion chamber and the turbine (the convergent transition section has a convergent shape and a gradually expanding internal chamber).

[0038] FG represents the process of rotating detonation combustion products impacting the turbine. The high-temperature, high-speed airflow of these detonation products is less uniform. The guide vanes of the turbine's front guide vane guide the airflow and reduce flow field nonuniformity. Subsequently, the more uniform detonation products impact the turbine, generating work. The high-speed rotation of the turbine drives the high-speed rotation of the compressor on the turbine shaft, which then generates work.

[0039] Finally, the detonation products pass through the turbine and exit the engine to generate thrust.

[0040] The above-described structure is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements or improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A rotating detonation turbine engine device, comprising a combustion chamber, an ignition hole and a fuel injection hole arranged on the combustion chamber, characterized in that: The combustion chamber is an annular combustion chamber consisting of a combustion chamber shell and a combustion chamber inner shell, and the combustion chamber shell is provided with an ignition hole and a fuel injection hole; A shaft sleeve is provided in the combustion chamber casing, and the shaft sleeve rotatably supports the turbine-compressor shaft; The front and rear ends of the turbine-compressor shaft are respectively fixed with a centrifugal compressor and an axial-flow turbine; the centrifugal compressor is used to compress external air into the combustion chamber; The turbine-compressor shaft passes through the rotating detonation annular combustion chamber, and the annular combustion chamber is coaxial with the rotor assembly; The front and rear ends of the combustion chamber casing are respectively fixed with a compressor casing and a turbine casing; A pressure diffuser buffer chamber is provided between the compressor casing and the combustion chamber inner casing, for accelerating and rectifying the incoming air into the combustion chamber and suppressing the forward propagation of the movement shock wave of the combustion chamber; an air injection annular gap is provided between the pressure diffuser buffer chamber and the front section of the annular combustion chamber; A fuel collecting chamber is provided between the compressor casing and the combustion chamber casing. A plurality of fuel injection holes are evenly arranged around the fuel collecting chamber. The fuel injection holes are located in the front section of the annular combustion chamber and are used to inject fuel and mix it with air. The ignition hole is located in the middle section of the annular combustion chamber and is used to ignite the mixed fuel and form a rotating detonation wave. The detonation products drive the turbine to rotate, and the turbine shaft drives the compressor to rotate at high speed, realizing the self-priming function of the compressor. A turbine guide is provided at the rear end of the combustion chamber inner shell for rectifying the working medium discharged from the combustion chamber outlet, reducing the amplitude of high-frequency pressure oscillation at the combustion chamber outlet, guiding the airflow to impact the turbine blades, and improving the matching between the combustion chamber and the turbine.

2. The rotating detonation turbine engine device according to claim 1, characterized in that: The turbine-compressor shaft is supported in the shaft sleeve by bearings.

3. The rotating detonation turbine engine device according to claim 2, characterized in that: It also includes cooling and lubrication devices for lubrication of shafts and bearings.

4. The rotating detonation turbine engine device according to claim 3, characterized in that: The lubrication method uses an electric pump for automatic lubrication, which is transported to the bearings of the centrifugal compressor and axial flow turbine through oil pipes.

5. The rotating detonation turbine engine device according to claim 3, characterized in that: The starting method is motor starting.

6. The rotating detonation turbine engine device according to claim 1, characterized in that: It has three ignition modes, namely low-energy spark plug ignition, high-energy spark plug ignition and pre-detonation tube ignition.

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