Metal fuel ramjet engine, aircraft and operation method of metal fuel engine

Abstract

The invention provides a metal fuel ramjet engine, an aircraft and an operation method of the metal fuel ramjet engine, and relates to the technical field of aerospace. A heat conduction device is connected with a molten metal injection device and is in heat conduction connection with an engine runner and / or an aircraft body; metal fuel in a molten state is injected into an engine runner through the molten metal injection device, and high-enthalpy air incoming flow and the molten metal fuel are fully mixed and combusted in the engine runner so as to do work to generate propulsive force. Besides, the metal fuel is heated through heat of the engine runner and the aircraft body, it can be ensured that the metal fuel is kept in a molten state, cooling and heat absorption can be conducted on the engine body and the high-temperature wall face of the runner, the equivalent fuel energy and the energy utilization rate are improved, and the working condition requirement of the high flight Mach number is better met; and compared with powder fuel supply, the molten metal fuel supply structure is easier to arrange, and the structural size of the engine is easier to reduce.

Description

Technical Field

[0001] The present invention relates to the field of aerospace technology, and in particular to a metal fuel ramjet engine, an aircraft and a metal fuel engine operating method. Background Art

[0002] Due to the insufficient heat release of hydrocarbon fuel ramjet engines at high Mach numbers, the maximum Mach number of the aircraft is difficult to exceed Mach 10. Although the flight speed of hydrogen fuel ramjet engines can reach Mach 10, there are still many application restrictions due to fuel storage issues. In order to increase the calorific value of the fuel, although powdered fuel can be used, the powder supply system is large and requires carrier gas for fluidization or dispersion, and the powder filling rate is difficult to exceed 0.8, which still limits the equivalent fuel energy.

[0003] In addition, the heat generated by the airframe and engine of a hypersonic aircraft is relatively high, and the heat sink of liquid hydrocarbon fuel cannot meet its cooling requirements, which will shorten the service life of the aircraft airframe and engine. Summary of the invention

[0004] The object of the present invention is to provide a metal fuel ramjet engine, an aircraft and a metal fuel engine operation method, so as to alleviate the technical problem that the ramjet engine is difficult to meet the energy demand of high flight Mach number.

[0005] In a first aspect, the present invention provides a metal fuel ramjet engine, comprising:

[0006] An engine flow passage, the engine flow passage is used to take in air and mix the metal fuel in a molten state, and the metal fuel in a molten state is burned to generate a propulsion force;

[0007] A molten metal injection device, the molten metal injection device is used to inject metal fuel in a molten state into the engine flow channel;

[0008] A heat conducting device is connected to the molten metal injection device, and the heat conducting device is heat-conductingly connected to the engine flow channel and / or the aircraft body.

[0009] In combination with the first aspect, the present invention provides a first possible implementation of the first aspect, wherein the molten metal injection device comprises: a nitrogen high-pressure tank, a metal fuel storage tank and a molten metal nozzle;

[0010] The heat conducting device is connected to the metal fuel storage compartment, and the nitrogen high-pressure tank, the metal fuel storage compartment and the molten metal nozzle are connected in sequence.

[0011] In combination with the first possible implementation of the first aspect, the present invention provides a second possible implementation of the first aspect, wherein the heat conducting device includes a fuel pipeline connecting the metal fuel storage tank and the molten metal nozzle;

[0012] The fuel line extends through a side wall of the engine runner and the aircraft body.

[0013] In combination with the second possible implementation of the first aspect, the present invention provides a third possible implementation of the first aspect, wherein the fuel pipeline extends to the tail of the aircraft body to vaporize the molten metal in the fuel pipeline and spray it out at the tail of the aircraft body.

[0014] In combination with the first aspect, the present invention provides a fourth possible implementation of the first aspect, wherein the metal fuel ramjet engine further comprises: a heat exchanger, a heat exchange pipeline, a steam raw material storage tank, a steam nozzle and a steam release valve;

[0015] The heat conducting device is connected to the heat exchanger, and the heat exchanger and the steam raw material storage tank are respectively connected to the heat exchange pipeline;

[0016] The steam nozzle is in fluid communication with the steam material storage tank, an open end of the steam nozzle is located at the tail of the aircraft body, and the steam release valve is installed on the steam nozzle.

[0017] In a second aspect, the present invention provides an aircraft equipped with the metal fuel ramjet engine described in the first aspect.

[0018] In a third aspect, the present invention provides a method for operating a metal fuel engine, comprising the following steps:

[0019] Using the heat from the engine flow passage and / or the aircraft body to heat the metal fuel so that the metal fuel reaches a molten state;

[0020] Injecting the metal fuel in a molten state into the engine flow passage;

[0021] Air and molten metal fuel are mixed and ignited in the engine flow path to generate propulsion.

[0022] In combination with the third aspect, the present invention provides a first possible implementation of the third aspect, wherein the metal fuel engine operation method further includes:

[0023] The metal fuel in a molten state is guided along the fuel pipeline to the side wall of the engine flow channel and the aircraft body to dissipate heat from the side wall of the engine flow channel and the aircraft body.

[0024] In combination with the first possible implementation of the third aspect, the present invention provides a second possible implementation of the third aspect, wherein the metal fuel engine operation method further includes:

[0025] The metal fuel in a molten state is made to flow toward the tail of the aircraft body, and is vaporized and ejected at the tail of the aircraft body.

[0026] In combination with the third aspect, the present invention provides a third possible implementation of the third aspect, wherein the metal fuel engine operation method further includes:

[0027] The steam raw material is heated by utilizing the heat of the engine flow passage and / or the aircraft body, and the steam generated by the heated steam raw material is ejected at the tail of the aircraft body.

[0028] The embodiments of the present invention bring about the following beneficial effects: a heat conducting device is used to connect a molten metal injection device, and the heat conducting device is heat-conductingly connected to the engine flow path and / or the aircraft body, and metal fuel in a molten state is injected into the engine flow path through the molten metal injection device. The engine flow path takes in air and mixes the metal fuel in a molten state, and the metal fuel in a molten state is burned to generate propulsion. The heat of the engine flow path and the aircraft body can be used to heat the metal fuel. On the one hand, it can ensure that the metal fuel remains in a molten state, and on the other hand, the waste heat of the engine flow path and the aircraft body can be used, which not only improves the equivalent fuel energy and energy utilization rate, and is more suitable for the energy requirements of high flight Mach numbers, but also the molten metal fuel supply structure is easier to arrange than the powder fuel supply, and it is easier to reduce the structural size of the engine.

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the related technologies, the drawings required for use in the specific embodiments or the related technical descriptions will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 A schematic diagram of a metal fuel ramjet engine provided in an embodiment of the present invention.

[0032] Icons: 100 - engine flow passage; 110 - air inlet; 120 - isolation section; 130 - main combustion chamber; 131 - cavity; 140 - tail nozzle; 200 - molten metal injection device; 201 - injection port; 210 - nitrogen high-pressure tank; 220 - metal fuel storage tank; 230 - molten metal nozzle; 300 - heat transfer device; 310 - fuel pipeline; 400 - aircraft body; 500 - heat exchanger; 600 - heat exchange pipeline; 700 - steam raw material storage tank; 800 - steam nozzle; 900 - steam release valve. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are only used to describe the difference in names, and cannot be understood as indicating or implying relative importance. The physical quantities in the formula, if not separately marked, should be understood as basic quantities of the basic units of the International System of Units, or derived quantities derived from the basic quantities through mathematical operations such as multiplication, division, differentiation or integration.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] like Figure 1 As shown, the metal fuel ramjet engine provided by the embodiment of the present invention includes:

[0037] The engine flow passage 100 is used for taking in air and mixing the metal fuel in a molten state, and the metal fuel in a molten state is burned to generate a propulsion force;

[0038] The molten metal injection device 200 is used to inject the metal fuel in a molten state into the engine flow channel 100. The injection method can be straight-flow injection, support plate injection, or wall vertical injection, etc.;

[0039] The heat conducting device 300 is connected to the molten metal injection device 200 , and at least one of the engine flow channel 100 and the aircraft body 400 is heat-conductively connected to the heat conducting device 300 .

[0040] In this embodiment, the residual heat of the engine flow passage 100 and the aircraft body 400 is used to heat the metal fuel through the heat conducting device 300, so that the metal fuel can be maintained in a molten state. The molten metal fuel supply structure is easier to arrange than the powder fuel supply, and it is easier to reduce the structural size of the engine. In addition, the molten metal fuel has a higher energy density, and the energy utilization rate is higher when the residual heat of the engine flow passage 100 and the aircraft body 400 is used, which is more suitable for the energy demand of high flight Mach number.

[0041] In the embodiment of the present invention, the engine flow passage 100 includes an air inlet passage 110 , an isolation section 120 , a main combustion chamber 130 and a tail nozzle 140 which are connected in sequence, and the injection port 201 of the molten metal injection device 200 is arranged in the main combustion chamber 130 .

[0042] Specifically, a shielding portion or a flow guide angle is provided at one end of the isolation section 120 connected to the air inlet 110 to ensure that the airflow can flow from the air inlet 110 into the isolation section 120 and to prevent the gas from flowing back from the isolation section 120 to the air inlet 110. In the cross section perpendicular to the propulsion direction, the cross-sectional area of ​​the main combustion chamber 130 is larger than the cross-sectional area of ​​the isolation section 120, so that the molten metal fuel and air can be fully mixed in the main combustion chamber 130 to achieve full combustion. In addition, the cross-sectional area of ​​the pipeline from the main combustion chamber 130 to the tail nozzle 140 along the propulsion direction increases in the perpendicular direction to the propulsion direction, thereby reducing the resistance encountered in the gas ejection process, and then giving full play to the propulsion force of the metal fuel ramjet engine.

[0043] Furthermore, the inner wall of the main combustion chamber 130 is recessed to form a cavity 131, and the injection port 201 faces the cavity 131, wherein the cavity 131 is located at one end of the main combustion chamber 130 close to the isolation section 120, so that the cross-sectional area of ​​the end of the main combustion chamber 130 close to the isolation section 120 perpendicular to the propulsion direction is larger than the cross-sectional area of ​​the isolation section 120. The cavity 131 has a combustion stabilizing effect and can improve the mixing degree of the molten metal and the high enthalpy air. In the main combustion chamber 130, the cross-sectional area of ​​the pipeline from the cavity 131 to the tail nozzle 140 perpendicular to the propulsion direction increases gradually.

[0044] Furthermore, the molten metal injection device 200 includes: a nitrogen high-pressure tank 210, a metal fuel storage chamber 220 and a molten metal nozzle 230; the heat conductive device 300 is connected to the metal fuel storage chamber 220, and the nitrogen high-pressure tank 210, the metal fuel storage chamber 220 and the molten metal nozzle 230 are connected in sequence.

[0045] In an optional embodiment, the heat conducting device 300 may be made of a heat conducting material or a pipe for circulating a heat conducting medium to transfer heat from at least one of the engine runner 100 and the aircraft body 400 to the metal fuel storage compartment 220, thereby heating the metal fuel, and driving the molten metal in the metal fuel storage compartment 220 through the high-pressure nitrogen in the nitrogen high-pressure tank 210 to spray into the main combustion chamber 130 of the engine runner 100 through the molten metal nozzle 230.

[0046] In this embodiment, the heat conducting device 300 includes a fuel pipeline 310 connecting the metal fuel storage compartment 220 and the molten metal nozzle 230; the fuel pipeline 310 extends through the side wall of the engine flow channel 100 and the aircraft body 400. On the one hand, the molten metal in the metal fuel storage compartment 220 can flow to the molten metal nozzle 230 through the fuel pipeline 310, and on the other hand, the fuel pipeline 310 extends through the side wall of the engine flow channel 100 and the aircraft body 400, so that the molten metal can directly absorb the heat of the engine flow channel 100 and the aircraft body 400, thereby achieving heat dissipation of the engine and the aircraft body 400, and improving energy utilization.

[0047] It should be noted that metal blocks can be stored in the metal fuel storage compartment 220 to increase the equivalent fuel energy of the fuel. The metal fuel can be made of high-energy solid materials such as magnesium, lithium, magnesium-aluminum alloy, and magnesium-boron alloy.

[0048] In an optional embodiment, the fuel line 310 extends to the tail of the aircraft body 400, so as to gasify the molten metal in the fuel line 310 and eject it at the tail of the aircraft body 400. The fuel line 310 extending to the tail of the aircraft body 400 has a longer heating distance, and the molten metal inside it is heated to a greater extent, so it can be further heated to the boiling point, and the gas generated can be ejected from the tail of the aircraft body 400, thereby increasing the thrust.

[0049] In this embodiment, the metal fuel ramjet engine further comprises: a heat exchanger 500, a heat exchange pipeline 600, a steam raw material storage tank 700, a steam nozzle 800 and a steam release valve 900; the heat conducting device 300 is connected to the heat exchanger 500, the heat exchanger 500 and the steam raw material storage tank 700 are respectively connected to the heat exchange pipeline 600; the steam nozzle 800 is fluidly connected to the steam raw material storage tank 700, the open end of the steam nozzle 800 is located at the tail of the aircraft body 400, and the steam release valve 900 is installed on the steam nozzle 800. The steam raw material is selected from metals or solids with low boiling points, such as sodium blocks, lithium blocks, etc., which can be gasified after being heated and sprayed out through the steam nozzle 800.

[0050] Among them, the heat of the molten metal in the fuel pipeline 310 can also be absorbed by the heat exchanger 500, thereby further improving the thermal energy utilization rate of the engine flow channel 100 and the aircraft body 400. The heat energy absorbed by the heat exchanger 500 is transferred to the steam raw material storage tank 700 through the heat exchange pipeline 600, which can heat and vaporize the steam raw material in the steam raw material storage tank 700. The generated steam can be ejected when the steam release valve 900 is in the open state, thereby providing additional jet thrust and improving the thrust performance of the engine.

[0051] The aircraft provided in the embodiment of the present invention is equipped with the metal-fuel ramjet engine described in the above embodiment. The aircraft has the technical effects of the above metal-fuel ramjet engine, which will not be described in detail here.

[0052] The metal fuel engine operation method provided by the embodiment of the present invention comprises the following steps:

[0053] The metal fuel is heated by using the heat of the engine flow passage 100 and / or the aircraft body 400 so as to make the metal fuel reach a molten state;

[0054] Injecting the molten metal fuel into the engine flow passage 100;

[0055] Air and metal fuel in a molten state are mixed and ignited within the engine runner 100 to generate propulsion.

[0056] In this embodiment, aluminum blocks are preferably used as metal fuel, and at least one pair of aluminum blocks in the engine flow channel 100 and the aircraft body 400 are heated to form a molten state, and the molten metal injected into the engine flow channel 100 is dispersed and atomized by the supersonic intake air to achieve sufficient mixing, and ignited by an igniter or the flame of the previous stroke, thereby generating propulsion.

[0057] In the embodiment of the present invention, the metal fuel engine operation method further includes: directing the metal fuel in a molten state along the fuel pipeline 310 to the side wall of the engine flow channel 100 and the aircraft body 400 to dissipate heat from the side wall of the engine flow channel 100 and the aircraft body 400. On the one hand, the heat of the engine flow channel 100 and the aircraft body 400 is used to heat the metal fuel, and on the other hand, the molten metal fuel has a heat dissipation effect on the side wall of the engine flow channel 100 and the aircraft body 400, which can prevent the side wall of the engine flow channel 100 and the aircraft body 400 from continuously heating up to exceed the temperature limit that the structure can withstand.

[0058] In addition, the metal fuel in a molten state can flow to the tail of the aircraft body 400, thereby increasing the heating range and heating time of the molten metal, and then the molten metal can reach a boiling point and vaporize and eject at the tail of the aircraft body 400 to generate additional thrust.

[0059] Furthermore, the metal fuel engine operation method also includes: utilizing heat from at least one of the engine flow passage 100 and the aircraft body 400 to heat the steam feedstock, and causing the steam generated by the heating of the steam feedstock to be ejected at the tail of the aircraft body 400, thereby improving the thermal energy utilization rate of the engine flow passage 100 and the aircraft body 400, and being able to generate additional thrust by steam injection.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A metal fuel ramjet engine, characterized in that: include: An engine flow passage (100), the engine flow passage (100) being used to take in air and mix the metal fuel in a molten state, and to generate propulsion force through combustion of the metal fuel in a molten state; A molten metal injection device (200), the molten metal injection device (200) being used to inject metal fuel in a molten state into the engine flow channel (100); A heat conducting device (300) is connected to the molten metal injection device (200), and the heat conducting device (300) is heat-conductingly connected to the engine flow channel (100) and / or the aircraft body (400).

2. The metal fuel ramjet engine according to claim 1, characterized in that: The molten metal injection device (200) comprises: a nitrogen high-pressure tank (210), a metal fuel storage compartment (220) and a molten metal nozzle (230); The heat conducting device (300) is connected to the metal fuel storage chamber (220), and the nitrogen high-pressure tank (210), the metal fuel storage chamber (220) and the molten metal nozzle (230) are sequentially connected.

3. The metal fuel ramjet engine according to claim 2, characterized in that: The heat conducting device (300) comprises a fuel pipeline (310) connecting the metal fuel storage tank (220) and the molten metal nozzle (230); The fuel line (310) extends through a side wall of the engine runner (100) and the aircraft body (400).

4. The metal fuel ramjet engine according to claim 3, characterized in that: The fuel pipeline (310) extends to the tail of the aircraft body (400) so as to gasify the molten metal in the fuel pipeline (310) and spray it out at the tail of the aircraft body (400).

5. The metal fuel ramjet engine according to claim 1, characterized in that: The metal fuel ramjet engine further comprises: a heat exchanger (500), a heat exchange pipeline (600), a steam raw material storage tank (700), a steam nozzle (800) and a steam release valve (900); The heat conducting device (300) is connected to the heat exchanger (500), and the heat exchanger (500) and the steam raw material storage tank (700) are respectively connected to the heat exchange pipeline (600); The steam nozzle (800) is fluidically connected to the steam raw material storage tank (700), the open end of the steam nozzle (800) is located at the tail of the aircraft body (400), and the steam release valve (900) is installed on the steam nozzle (800).

6. An aircraft, characterized in that: The aircraft is equipped with the metal fuel ramjet engine according to any one of claims 1 to 5.

7. A method for operating a metal fuel engine, characterized in that: The following steps are involved: Using the heat of the engine flow passage (100) and / or the aircraft body (400) to heat the metal fuel so that the metal fuel reaches a molten state; Injecting the metal fuel in a molten state into the engine flow channel (100); Air and molten metal fuel are mixed and ignited in an engine flow passage (100) to generate propulsion.

8. The metal fuel engine operating method according to claim 7, characterized in that: The metal fuel engine operation method further comprises: The metal fuel in a molten state is guided along a fuel pipeline (310) to the side wall of an engine flow channel (100) and an aircraft body (400) to dissipate heat from the side wall of the engine flow channel (100) and the aircraft body (400).

9. The metal fuel engine operating method according to claim 8, characterized in that: The metal fuel engine operation method further comprises: The metal fuel in a molten state is made to flow toward the tail of the aircraft body (400), and is vaporized and ejected at the tail of the aircraft body (400).

10. The metal fuel engine operating method according to claim 8, characterized in that: The metal fuel engine operation method further comprises: The steam raw material is heated by utilizing the heat of the engine flow passage (100) and / or the aircraft body (400), and the steam generated by the heated steam raw material is ejected at the tail of the aircraft body (400).

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