Rotary detonation engine

Abstract

We provide a rotary detonation engine that can compress an oxidizer without using exhaust gases. [Solution] A rotary detonation engine according to one aspect of the present disclosure includes a combustor having a cooling mechanism and generating a rotary detonation wave, a compressor for compressing an oxidant, a turbine for rotationally driving the compressor, a combustion oxidant passage for supplying the oxidant compressed by the compressor into the combustor, a cooling oxidant passage for supplying the oxidant compressed by the compressor to the cooling mechanism as a refrigerant, and a turbine oxidant passage for supplying the oxidant that has passed through the cooling mechanism to the turbine as a working fluid.

Description

Technical Field

[0001] The present disclosure relates to a rotating detonation engine.

Background Art

[0002] A rotating detonation engine is an engine that generates a rotating detonation wave in which a flame front accompanied by a shock wave propagates supersonically while rotating circumferentially inside a combustor, and rapidly burns fuel (see Patent Document 1 below).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a rotating detonation engine, an oxidizer such as air must be compressed and supplied inside the combustor. As a method of compressing the oxidizer, a method of driving a turbine by exhaust gas discharged from the combustor and compressing the oxidizer by a compressor connected to the turbine can be considered. However, since the exhaust gas of a rotating detonation engine has a very high temperature and very large pressure fluctuations, the turbine may not be able to withstand the temperature and pressure fluctuations.

[0005] An object of the present disclosure is to provide a rotating detonation engine that can compress an oxidizer without using exhaust gas.

Means for Solving the Problems

[0006] A rotary detonation engine according to one aspect of the present disclosure includes a combustor having a cooling mechanism and generating a rotary detonation wave, a compressor for compressing an oxidant, a turbine for rotationally driving the compressor, a combustion oxidant passage for supplying the oxidant compressed by the compressor into the combustor, a cooling oxidant passage for supplying the oxidant compressed by the compressor to the cooling mechanism as a refrigerant, and a turbine oxidant passage for supplying the oxidant that has passed through the cooling mechanism to the turbine as a working fluid.

[0007] Furthermore, a rotary detonation engine according to another aspect of the present disclosure includes a combustor that generates a rotary detonation wave and has a cooling mechanism, a compressor that compresses an oxidizer, a turbine that rotates the compressor, a fuel tank for storing fuel, a combustion oxidizer passage for supplying the oxidizer compressed by the compressor into the combustor, a cooling fuel passage for supplying the fuel stored in the fuel tank as a coolant to the cooling mechanism, and a turbine fuel passage for supplying the fuel that has passed through the cooling mechanism as a working fluid to the turbine. [Effects of the Invention]

[0008] According to the rotary detonation engine described above, the oxidizer can be compressed without using exhaust gases. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a diagram of the rotary detonation engine according to the first embodiment. [Figure 2] Figure 2 is a diagram of the rotary detonation engine according to the second embodiment. [Modes for carrying out the invention]

[0010] (First Embodiment) First, a rotary detonation engine (hereinafter simply referred to as "engine") 100 according to the first embodiment will be described. Figure 1 is a system diagram of the engine 100 according to the first embodiment. Although the engine 100 of this embodiment is for aircraft, the application of the engine 100 is not limited. Below, the device configuration of the engine 100 will be described, followed by the flow path system of the engine 100.

[0011] <Device configuration> First, the configuration of the engine 100 will be described. As shown in Figure 1, the engine 100 according to this embodiment is equipped with a combustor 11. The combustor 11 is a device that burns fuel mixed with an oxidizer. The fuel in this embodiment is, for example, hydrogen, but it may also be kerosene, jet fuel, methane, ethanol, etc. The fuel may be a liquid fuel or a gaseous fuel. Also, the oxidizer in this embodiment is air taken in from the outside, but it may also be oxygen or nitrous oxide, etc. The combustor 11 in this embodiment is a rotary detonation combustor that generates a rotary detonation wave. The combustor 11 in this embodiment has a cylindrical outer cylinder 12 and a cylindrical inner cylinder 13 located inside the outer cylinder 12. A cylindrical combustion chamber 14 is formed between the outer cylinder 12 and the inner cylinder 13, and the rotary detonation wave propagates while rotating circumferentially along this combustion chamber 14. The engine 100 can generate thrust or extract work by injecting the high-temperature, high-pressure gas generated by the rotary detonation wave from an exhaust nozzle 16 located at the rear of the combustor 11. The structure of the combustor 11 is not limited. For example, the combustor 11 in this embodiment is of the annular type, but it may also be of the hollow type.

[0012] Furthermore, the combustor 11 has a cooling mechanism 15 for cooling the combustor 11. The cooling mechanism 15 in this embodiment is located on the outer circumference of the combustor 11, and the combustor 11 is cooled by the passage of a refrigerant through the cooling mechanism 15. The refrigerant of the cooling mechanism 15 is not limited, but as will be described later, an oxidizing agent is used as the refrigerant in this embodiment. The cooling mechanism 15 may be a pipe provided on the outer circumference of the combustor 11, or a groove formed on the outer circumference of the combustor 11. In addition, the cooling mechanism 15 may be configured to perform film cooling by forming a layer of refrigerant on the surface of the outer cylinder 12 facing the combustion chamber 14, forming a layer of refrigerant on the surface of the inner cylinder 13 facing the combustion chamber 14, or forming a layer of refrigerant on both surfaces.

[0013] As shown in Figure 1, the engine 100 includes a compressor 21, a turbine 22, and a power converter 23. The compressor 21 is a device that compresses the oxidizer supplied to the inside of the combustor 11. The turbine 22 is a device that rotates the compressor 21. The turbine 22 is connected to the compressor 21 via a shaft 24, and the compressor 21 rotates as the turbine 22 rotates. The turbine 22 rotates using the energy of the working fluid. The working fluid of the turbine 22 is not limited, but as will be described later, in this embodiment an oxidizer is used as the working fluid.

[0014] The type of compressor 21 and turbine 22 is not particularly limited and may be of any type, such as axial flow, mixed flow, or centrifugal (radial) type. The trapezoidal figures showing the compressor 21 and turbine 22 in the diagram are merely schematic diagrams for explanatory purposes, and the shape of the figures does not limit the shape, number of stages, inflow direction, blade structure, etc., of the compressor 21 and turbine 22.

[0015] The power converter 23 is a device that converts power obtained from the turbine 22 into power to drive other equipment. This "other equipment" includes the fuel pump 32, which will be described later. The power converter 23 is connected to the turbine 22 via the shaft 24, and the power converter 23 is driven by the rotation of the turbine 22. For example, if the "other equipment" is an electric powered device, the power converter 23 is a generator and converts the power obtained from the turbine 22 into electric power. Also, for example, if the "other equipment" is a hydraulic fluid powered device, the power converter 23 is a booster pump and converts the power obtained from the turbine 22 into hydraulic fluid pressure. In Figure 1, the power converter 23 is located on the opposite side of the turbine 22, with the compressor 21 in between, but the position of the power converter 23 is not limited. For example, the power converter 23 may be located between the compressor 21 and the turbine 22. Also, a gearbox may be interposed between the power converter 23 and the shaft 24.

[0016] As shown in Figure 1, the engine 100 is equipped with a fuel tank 31 and a fuel pump 32. The fuel tank 31 is a tank for storing fuel. In this embodiment, the fuel tank 31 stores fuel in a liquefied state. For example, if the fuel for the engine 100 is hydrogen, the fuel tank 31 stores the fuel in the form of liquefied hydrogen. Therefore, the fuel stored in the fuel tank 31 is at a very low temperature. However, if the fuel is kerosene or jet fuel, the fuel tank 31 stores the fuel at room temperature. The fuel pump 32 is a pump for pressurizing the fuel. The power source for driving the fuel pump 32 is not limited, but in this embodiment, power is supplied from the power converter 23 described above.

[0017] Furthermore, as shown in Figure 1, the engine 100 is equipped with a heat exchanger 41. The heat exchanger 41 is a device for heating the fuel supplied to the inside of the combustor 11. As will be described later, the heat exchanger 41 in this embodiment heats the fuel by exchanging heat between the fuel and the oxidizer. In this embodiment, as the fuel passes through the heat exchanger 41, the fuel changes from a liquid state to a gaseous state. However, the fuel may remain in a liquid state before and after passing through the heat exchanger 41, or it may remain in a gaseous state. In other words, if the fuel is in a liquid state, it may evaporate and burn inside the combustor 11.

[0018] <Flow System> Next, the flow path system of the engine 100 will be described. As shown in Figure 1, the engine 100 according to this embodiment includes a compressed oxidant flow path 51 that takes in air, which is an oxidant, from the outside and supplies it to the compressor 21, and a combustion oxidant flow path 52 that supplies the oxidant compressed by the compressor 21 into the combustor 11. As a result, in this embodiment, a compressed oxidant with high pressure can be supplied into the combustor 11.

[0019] Furthermore, the engine 100 according to this embodiment includes a cooling oxidant flow path 53 that supplies the oxidant compressed by the compressor 21 to the cooling mechanism 15 as a refrigerant, and a turbine oxidant flow path 54 that supplies the oxidant that has passed through the cooling mechanism 15 to the turbine 22 as a working fluid. By supplying the oxidant to the cooling mechanism 15, the combustor 11 is cooled by the oxidant, while the oxidant is heated by the heat generated from the combustor 11. The turbine 22 is then driven by the energy of the oxidant heated in the cooling mechanism 15. Therefore, according to the engine 100 according to this embodiment, the turbine 22 can be driven without using exhaust gas discharged from the combustor 11, and the oxidant supplied to the inside of the combustor 11 can be compressed.

[0020] In addition, the engine 100 according to the present embodiment includes an exhaust oxidant flow path 55 that discharges an oxidant from the turbine 22, and a combustion fuel flow path 61 that supplies the fuel stored in the fuel tank 31 to the inside of the combustor 11. The fuel pump 32 described above is located in the combustion fuel flow path 61. Further, the heat exchanger 41 described above is located across the combustion fuel flow path 61 and the exhaust oxidant flow path 55. Therefore, in the heat exchanger 41, heat exchange is performed between the fuel passing through the combustion fuel flow path 61 and the oxidant passing through the exhaust oxidant flow path 55. Thus, according to the engine 100 according to the present embodiment, since the fuel is heated by using the heat of the oxidant, the fuel can be efficiently heated.

[0021] In addition, the engine 100 according to the present embodiment includes a tank oxidant flow path 56 that supplies the oxidant compressed by the compressor 21 to the fuel tank 31. Therefore, a high-pressure oxidant is supplied into the fuel tank 31. As a result, since the pressure in the fuel tank 31 increases, the fuel can be efficiently discharged from the fuel tank 31.

[0022] In addition, the engine 100 according to the present embodiment includes a power transmission path 71 that transmits power from the power conversion device 23 to the fuel pump 32. For example, when power is supplied from the power conversion device 23 to the fuel pump 32, the power transmission path 71 is an electric wire. Further, for example, when the pressure of the hydraulic oil is supplied from the power conversion device 23 to the fuel pump 32, the power transmission path 71 is a hydraulic oil pipe. Thus, in the present embodiment, since the fuel pump 32 is driven by the power obtained from the turbine 22 via the power conversion device 23, devices such as a battery for driving the fuel pump 32 can be omitted or the capacity can be suppressed. Note that when the power conversion device 23 is a gear, for example, and directly mechanically drives the fuel pump 32, the power transmission path 71 is omitted.

[0023] (Second Embodiment) Next, the engine 200 according to the second embodiment will be described. Figure 2 is a system diagram of the engine 200 according to the second embodiment. The engine 100 according to the first embodiment uses an "oxidizer" heated by the cooling mechanism 15 as the working fluid for the turbine 22, whereas the engine 200 according to this embodiment uses "fuel" heated by the cooling mechanism 15 as the working fluid for the turbine 22. In the following, components of the engine 200 according to this embodiment that are the same as or correspond to components of the engine 100 according to the first embodiment will be denoted by the same reference numerals as the components of the engine 100 according to the first embodiment, and their descriptions will be omitted.

[0024] <Device configuration> The engine 200 according to this embodiment has basically the same equipment configuration as the engine 100 according to the first embodiment, except that it does not have a heat exchanger 41. However, fuel is supplied as a coolant to the cooling mechanism 15 of the combustor 11 instead of an oxidizer. Also, fuel heated in the cooling mechanism 15 is supplied as the working fluid to the turbine 22 instead of an oxidizer heated in the cooling mechanism 15.

[0025] <Flow System> The engine 200 according to this embodiment, like the engine 100 according to the first embodiment, is equipped with a compression oxidizer passage 51, a combustion oxidizer passage 52, a tank oxidizer passage 56, and a power transmission passage 71. On the other hand, the engine 200 according to this embodiment does not have the cooling oxidizer passage 53, turbine oxidizer passage 54, and exhaust oxidizer passage 55 that were provided in the engine 100 according to the first embodiment. In addition, the combustion fuel passage 61 in this embodiment has a different arrangement from the combustion fuel passage 61 in the first embodiment.

[0026] Furthermore, the engine 200 according to this embodiment includes, as components not provided by the engine 100 according to the first embodiment, a cooling fuel passage 62 that supplies fuel stored in the fuel tank 31 as a coolant to the cooling mechanism 15, and a turbine fuel passage 63 that supplies the fuel that has passed through the cooling mechanism 15 as a working fluid to the turbine 22.

[0027] By supplying fuel to the cooling mechanism 15, the combustor 11 is cooled by the fuel, while the fuel is heated by the heat generated from the combustor 11. The turbine 22 is then driven by the energy of the fuel heated by the cooling mechanism 15. Therefore, according to the engine 200 of this embodiment, the turbine 22 can be driven without using the exhaust gas discharged from the combustor 11, and the oxidizer supplied to the inside of the combustor 11 can be compressed.

[0028] Furthermore, the combustion fuel passage 61 in this embodiment is located downstream of the turbine 22 and supplies fuel discharged from the turbine 22 into the combustor 11. In the engine 200 according to this embodiment, the fuel supplied into the combustor 11 is heated by the cooling mechanism 15, so the heat exchanger 41 that was provided in the engine 100 according to the first embodiment is unnecessary. In this embodiment, as the fuel passes through the cooling mechanism 15, the fuel changes from a liquid state to a gaseous or supercritical state. However, the fuel may remain in a liquid state or a gaseous state before and after passing through the cooling mechanism 15. The above is a description of the embodiment.

[0029] The structure, flow path shape, and flow direction of the compressor 21 and turbine 22 can be modified as appropriate without departing from the gist of this disclosure. In particular, a configuration in which the turbine 22 is an axial-flow turbine and the compressor 21 is an axial-flow compressor is also included in this disclosure. Furthermore, this disclosure also includes modified configurations in which the compressor 21 and turbine 22 are combined with multi-stage, mixed-flow, and centrifugal types.

[0030] (summary) The rotary detonation engine in the first phase includes a combustor that generates a rotary detonation wave and has a cooling mechanism, a compressor that compresses an oxidizer, a turbine that rotates the compressor, a combustion oxidizer passage that supplies the oxidizer compressed by the compressor into the combustor, a cooling oxidizer passage that supplies the oxidizer compressed by the compressor to the cooling mechanism as a coolant, and a turbine oxidizer passage that supplies the oxidizer that has passed through the cooling mechanism to the turbine as a working fluid.

[0031] In this configuration, the turbine is driven by the energy of the oxidizer heated by the cooling mechanism. Therefore, the oxidizer supplied to the combustor can be compressed by driving the turbine without using exhaust gas at a temperature that the turbine cannot withstand.

[0032] The rotary detonation engine in the second phase includes, in the rotary detonation engine in the first phase, a fuel tank for storing fuel, a combustion fuel passage for supplying the fuel stored in the fuel tank into the combustor, an exhaust oxidizer passage for discharging oxidizer from the turbine, and a heat exchanger located across the combustion fuel passage and the exhaust oxidizer passage, which causes heat exchange between the fuel passing through the combustion fuel passage and the oxidizer passing through the exhaust oxidizer passage.

[0033] In this configuration, a heat exchanger can be used to heat the fuel supplied to the combustor using an oxidizer. Therefore, energy for heating the fuel can be secured efficiently.

[0034] The rotary detonation engine in the third phase includes, in the rotary detonation engine in the first phase, a fuel tank for storing fuel, a combustion fuel passage for supplying the fuel stored in the fuel tank into the combustor, a fuel pump located in the combustion fuel passage, and a power converter that converts power obtained from the turbine into power to drive the fuel pump.

[0035] In this configuration, the fuel pump is driven by power obtained from the turbine, thus efficiently securing the energy needed to drive the fuel pump.

[0036] The rotary detonation engine in the fourth phase includes, in the rotary detonation engine of the first phase, a fuel tank for storing fuel, a combustion fuel passage for supplying the fuel stored in the fuel tank into the combustor, and a tank oxidizer passage for supplying the oxidizer compressed by the compressor to the fuel tank.

[0037] In this configuration, the oxidizer compressed by the compressor increases the pressure inside the fuel tank, thus efficiently securing the energy needed to discharge fuel from the fuel tank.

[0038] The fifth phase of the rotary detonation engine includes a combustor that generates a rotary detonation wave and has a cooling mechanism, a compressor that compresses an oxidizer, a turbine that rotates the compressor, a fuel tank that stores fuel, a combustion oxidizer passage that supplies the oxidizer compressed by the compressor into the combustor, a cooling fuel passage that supplies the fuel stored in the fuel tank as a coolant to the cooling mechanism, and a turbine fuel passage that supplies the fuel that has passed through the cooling mechanism as a working fluid to the turbine.

[0039] In this configuration, the turbine is driven by the energy of fuel heated by the cooling mechanism. Therefore, the oxidizer supplied to the combustor can be compressed by driving the turbine without using exhaust gas at a temperature that the turbine cannot withstand.

[0040] The rotary detonation engine in the sixth phase is equipped with a fuel pump located in the cooling fuel passage and a power converter that converts power obtained from the turbine into power to drive the fuel pump, in addition to the rotary detonation engine in the fifth phase.

[0041] In this configuration, the fuel pump is driven by power obtained from the turbine, thus efficiently securing the energy needed to drive the fuel pump.

[0042] The rotary detonation engine in the seventh phase is equipped with a tank oxidizer passage that supplies the oxidizer compressed by the compressor to the fuel tank, as in the rotary detonation engine in the fifth or sixth phase.

[0043] In this configuration, the oxidizer compressed by the compressor increases the pressure inside the fuel tank, thus efficiently securing the energy needed to discharge fuel from the fuel tank. [Explanation of Symbols]

[0044] 11 Combustor 15 Cooling mechanism 21 Compressor 22 Turbines 23 Power converter 31 Fuel tank 32 Fuel pump 41 Heat exchanger 52 Combustion Oxidizer Flow Channel 53 Cooling oxidizer channel 54 Turbine Oxidizer Flow Channel 55 Exhaust oxidant flow path 56 Tank oxidizer flow path 61 Combustion fuel flow path 62 Cooling fuel passage 63 Turbine fuel passage 100, 200 RPM detonation engine

Claims

1. A combustor having a cooling mechanism and generating a rotational detonation wave, A compressor for compressing the oxidizing agent, A turbine that rotates the compressor, A combustion oxidant flow path supplies the oxidant compressed by the compressor into the combustor, A cooling oxidant channel that supplies the oxidant compressed by the compressor as a refrigerant to the cooling mechanism, A rotary detonation engine comprising a turbine oxidizer flow path that supplies the oxidizer that has passed through the cooling mechanism to the turbine as a working fluid.

2. A fuel tank for storing fuel, A combustion fuel passage that supplies fuel stored in the fuel tank into the combustor, A discharge oxidant channel for discharging the oxidant from the turbine, The rotary detonation engine according to claim 1, further comprising a heat exchanger positioned across the combustion fuel passage and the exhaust oxidizer passage, which causes heat exchange between the fuel passing through the combustion fuel passage and the oxidizer passing through the exhaust oxidizer passage.

3. A fuel tank for storing fuel, A combustion fuel passage that supplies fuel stored in the fuel tank into the combustor, A fuel pump located in the aforementioned combustion fuel passage, The rotary detonation engine according to claim 1, further comprising a power conversion device that converts the power obtained from the turbine into power to drive the fuel pump.

4. A fuel tank for storing fuel, A combustion fuel passage that supplies fuel stored in the fuel tank into the combustor, The rotary detonation engine according to claim 1, further comprising a tank oxidizer passage for supplying the oxidizer compressed by the compressor to the fuel tank.

5. A combustor having a cooling mechanism and generating a rotational detonation wave, A compressor for compressing the oxidizing agent, A turbine that rotates the compressor, A fuel tank for storing fuel, A combustion oxidant flow path supplies the oxidant compressed by the compressor into the combustor, A cooling fuel passage that supplies the fuel stored in the fuel tank to the cooling mechanism as a refrigerant, A rotary detonation engine comprising a turbine fuel passage that supplies fuel that has passed through the cooling mechanism to the turbine as a working fluid.

6. A fuel pump located in the aforementioned cooling fuel passage, The rotary detonation engine according to claim 5, further comprising a power conversion device that converts the power obtained from the turbine into power to drive the fuel pump.

7. The rotary detonation engine according to claim 5, further comprising a tank oxidizer passage for supplying the oxidizer compressed by the compressor to the fuel tank.

Images