Staged non-catalytic ignition non-toxic single-propellant engine and spacecraft

Abstract

The present invention provides a staged non-catalytic ignition non-toxic monopropellant engine and a spacecraft. The staged non-catalytic ignition non-toxic monopropellant engine comprises a branch ignition module, a main injector, a main combustion chamber and an engine nozzle; the end of the branch ignition module is located in the main combustion chamber, and a plurality of through holes are arranged in the middle and lower part of the branch ignition module, and the middle and lower part of the branch ignition module is connected with the main combustion chamber through the through holes. The branch ignition module comprises a branch injector, an igniter and a branch cavity, and the other end of the branch cavity is defined as a branch combustion chamber; the present invention overcomes the problem that large-flow non-toxic monopropellant is difficult to ignite by adopting a staged non-catalytic ignition scheme through the design of the branch combustion chamber and the main combustion chamber, and the engine adopts a non-catalytic ignition scheme, and does not need to use precious metal catalysts, which can save the cost of expensive catalysts, and can avoid the problems of catalyst temperature resistance limitation and the difficulty of self-control of precious metal raw materials.

Description

Technical Field

[0001] The present invention relates to the technical field of engines for spacecraft propulsion systems, and in particular to a staged non-catalytic ignition non-toxic single-component engine and a spacecraft. Background Art

[0002] At present, the hydrazine propellant used in the monopropellant propulsion system of spacecraft has a high inhalation carcinogenic toxicity and is flammable and explosive. As the whole society has stricter requirements for environmental protection and personnel health, it is imperative to develop non-toxic propulsion technology to replace toxic hydrazine propulsion technology.

[0003] At present, non-toxic monopropellant engines mainly use catalytic ignition. Since the theoretical combustion temperature of non-toxic monopropellant is high, the catalytic bed is easily damaged when using catalytic decomposition ignition, which shortens the life of the engine and catalyst.

[0004] For example, patent document CN201610022559.3 discloses an annular solid-liquid catalytic ignition engine, including an injector, a solid charge, an insulation layer, a catalytic net and an ignition engine casing. Among them, the injector is designed with an injection gap in the circumference, and a catalytic net is laid at the entrance of the injection gap; thus, the oxidant is introduced from the oxidant channel on the ignition engine casing, enters the annular flow channel in the ignition engine casing, and then catalytically decomposes through the catalytic net to produce high-temperature oxygen-rich gas, which is injected into the ignition engine combustion chamber through the injection gap gas, reacts with the solid charge to form a high-temperature combustion gas, and enters the main engine combustion chamber through the opening designed on the insulation layer to ignite the main engine. Although this solution is provided with an insulation layer and can realize multiple ignitions of the engine to a certain extent. However, it still adopts the catalytic ignition method, and does not avoid the problem of the catalytic bed being easily damaged and the short life of the engine and catalyst in principle.

[0005] The non-catalytic ignition HAN engine can avoid problems such as high-temperature deactivation of the catalyst and cold start, and has the advantages of high performance, good environmental adaptability, and high reliability. Therefore, research institutions in various countries have carried out a lot of research on the non-catalytic ignition of HAN-based propellants.

[0006] Research institutions and scholars at home and abroad have found that the ignition of non-toxic monopropellants requires high energy and a long ignition delay, making it difficult to ignite non-toxic monopropellants without catalysis. In addition, due to the long delay time and difficulty of ignition, the thrust generated by such engines is insufficient. Currently, they can only generate thrust of 0.1 to 10N. Summary of the invention

[0007] In view of the defects in the prior art, the purpose of the present invention is to provide a staged non-catalytic ignition non-toxic single-component engine and a spacecraft.

[0008] According to the present invention, a staged non-catalytic ignition non-toxic monopropellant engine is provided, comprising a branch ignition module, a main injector, a main combustion chamber and an engine nozzle;

[0009] The main injector and the engine nozzle are respectively installed at both ends of the main combustion chamber;

[0010] The branch ignition module is coaxially arranged with the main combustion chamber, and the end of the branch ignition module is located in the main combustion chamber. A plurality of through holes are arranged in the middle and lower part of the branch ignition module, and the middle and lower part of the branch ignition module is connected with the main combustion chamber through the through holes.

[0011] Preferably, the branch ignition module comprises a branch injector, an igniter and a branch cavity, the branch injector is installed at one end of the branch cavity, the igniter is installed in the branch cavity, and the other end of the branch cavity is defined as a branch combustion chamber;

[0012] The branch combustion chamber is provided with a plurality of through holes;

[0013] The branch injector comprises a branch injector core body, and the branch injector core body is used to atomize the non-toxic propellant in the branch injector into droplets;

[0014] The non-toxic propellant in the branch injector is atomized into droplets by the branch injector core, and then ignited by the igniter to become high-temperature combustion gas, which flows into the main combustion chamber through the through hole.

[0015] Preferably, the main injector comprises a main injector housing, a main injector core and a pressure measuring nozzle;

[0016] The main injection core and the pressure measuring nozzle are both installed on the injection housing; the main injection core is used to atomize the non-toxic propellant in the main injector into droplets;

[0017] The non-toxic propellant in the main injector enters from the main injection shell, is atomized into droplets under the action of the main injection core, and is sprayed into the main combustion chamber.

[0018] Preferably, the flow rate of the non-toxic propellant passing through the branch injector is 1 to 30% of the total flow rate of the non-toxic propellant in the staged non-catalytic ignition non-toxic monopropellant engine;

[0019] Preferably, the igniter is one of electric heat ignition, electrode ignition, laser ignition, torch ignition, and chemical self-ignition ignition.

[0020] Preferably, the plurality of through holes are arranged in a circumferential and radial array along the branch combustion chamber.

[0021] Preferably, the material of the branch injector and the main injector is one of titanium alloy, iron-based deformable high-temperature alloy, nickel-based deformable high-temperature alloy, cobalt-based deformable high-temperature alloy, and stainless steel.

[0022] Preferably, the material of the branch cavity and the main combustion chamber is one of niobium alloy, molybdenum alloy, platinum-rhodium alloy, platinum-iridium alloy, iridium-rhodium alloy, rhenium-iridium alloy, tungsten-rhenium alloy or tantalum-tungsten alloy.

[0023] Preferably, the non-toxic propellant is one or a mixture of hydroxylamine nitrate (HAN) based propellant, ammonium dinitramide (ADN) based propellant, hydrazine nitroformate (HNF) based propellant.

[0024] The present invention also provides a spacecraft, which adopts the staged non-catalytic ignition non-toxic single-component engine.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The present invention adopts a graded non-catalytic ignition scheme through the design of the branch combustion chamber and the main combustion chamber, which can overcome the problem of difficulty in ignition of large-flow non-toxic monopropellant. By solving the problem of difficulty in ignition, the overall output thrust of the engine is also improved.

[0027] 2. The engine adopts a non-catalytic ignition solution, which does not require the use of precious metal catalysts, saving the cost of expensive catalysts and avoiding problems such as the temperature resistance limitation of catalysts and the difficulty in independent control of precious metal raw materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0029] Figure 1 It is a working principle diagram of the present invention;

[0030] Figure 2 This is a cross-sectional view of an engine using an electric heat ignition solution of the present invention;

[0031] Figure 3 It is a cross-sectional view of the branch ignition module of the present invention;

[0032] Figure 4 Cross-section view of the main injector.

[0033] The figure shows:

[0034] DETAILED DESCRIPTION

[0035] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0036] Example 1: Example 1 is a basic example:

[0037] The present invention provides a staged non-catalytic ignition non-toxic single-component engine, such as Figure 1-4 As shown, it includes a branch ignition module 1, a main injector 2, a main combustion chamber 3 and an engine nozzle 4; the main injector 2 and the engine nozzle 4 are respectively installed at both ends of the main combustion chamber 3; specifically, the engine nozzle 4 is welded at the end of the main combustion chamber 3, and the engine nozzle 4 is a Laval nozzle. The length of the main combustion chamber 3 is 40 to 150 mm; the chamber pressure of the main combustion chamber 3 is 0.5 to 5 MPa;

[0038] The branch ignition module 1 is coaxially arranged with the main combustion chamber 3, and the end of the branch ignition module 1 is located in the main combustion chamber 3. A plurality of through holes 14 are provided in the middle and lower part of the branch ignition module 1, and the middle and lower part of the branch ignition module 1 is connected with the main combustion chamber 3 through the through holes 14.

[0039] like Figure 2 , 3 As shown, the branch ignition module 1 includes a branch injector 11, an igniter 12 and a branch cavity 13, the branch injector 11 is installed at one end of the branch cavity 13, and the igniter 12 is installed in the branch cavity 13. In a preferred example, the branch cavity 13 is connected to the main injector 2 by welding; the other end of the branch cavity 13 is defined as a branch combustion chamber 131; the igniter 12 is one of electric heat ignition, electrode ignition, laser ignition, torch ignition, and chemical self-ignition ignition. The branch combustion chamber 131 is provided with a plurality of through holes 14; specifically, the plurality of through holes 14 are arranged in a circumferential and radial array along the branch combustion chamber 131, the branch combustion chamber 131 is inserted into the main combustion chamber 3, the length of the branch combustion chamber 131 is 20 to 60% of the length of the main combustion chamber 3, the bottom of the branch combustion chamber 131 is a closed structure, and no holes are punched within a height range of 2 to 6 mm from the bottom, forming a reaction space, so that the non-toxic monopropellant that is not completely burned in the branch stays in the space, so that there is time for a full combustion reaction to occur.

[0040] The branch injector 11 includes a branch injector core, which is used to atomize the non-toxic propellant in the branch injector 11 into droplets; after the non-toxic propellant in the branch injector 11 is atomized into droplets by the branch injector core, it is ignited by the igniter 12 to become high-temperature combustion gas, and flows into the main combustion chamber 3 through the through hole 14. The non-toxic propellant in the branch injector 11 is a small flow rate propellant.

[0041] like Figure 2 , 4 As shown, the main injector 2 includes a main injection shell 21, a main injection core 22 and a pressure measuring nozzle 23; the main injection core 22 and the pressure measuring nozzle 23 are both installed on the injection shell 21; the main injection core 22 is used to atomize the non-toxic propellant in the main injector 2 into droplets; the non-toxic propellant in the main injector 2 enters from the main injection shell 21, is atomized into small droplets under the action of the main injection core 22, and is sprayed into the main combustion chamber 3. The engine working pressure is measured from the pressure measuring nozzle 23. The non-toxic propellant in the main injector 2 is a large-flow propellant. Specifically, the large-flow propellant is atomized into small droplets under the action of the injection core 22 by the impact atomization method, the impact angle range is 60 to 120°, and the impact synthesis angle range is -10 to 10°;

[0042] The non-toxic propellant is a mixture of one or more of hydroxylamine nitrate (HAN) based propellant, ammonium dinitramide (ADN) based propellant, and hydrazine nitroformate (HNF) based propellant. The flow rate of the non-toxic propellant passing through the branch injector 11 is 1 to 30% of the total flow rate of the non-toxic propellant in the staged non-catalytic ignition non-toxic monopropellant engine; preferably, the flow rate of the propellant passing through the branch ignition module 1 is 2 to 20% of the total flow rate.

[0043] The branch injector 11 and the main injector 2 are made of titanium alloy, iron-based deformed high-temperature alloy, nickel-based deformed high-temperature alloy, cobalt-based deformed high-temperature alloy, and stainless steel. The branch cavity 13 and the main combustion chamber 3 are made of niobium alloy, molybdenum alloy, platinum-rhodium alloy, platinum-iridium alloy, iridium-rhodium alloy, rhenium-iridium alloy, tungsten-rhenium alloy, or tantalum-tungsten alloy.

[0044] The working principle and process of the present invention are as follows:

[0045] refer to Figure 1 and Figure 2When the engine is working, a small flow of propellant is sprayed from the branch injector 11 into the branch cavity 13, and ignited under the action of the igniter 12; after the propellant is ignited, the igniter 12 stops working; the high-temperature combustion gas generated in the branch combustion chamber 131 enters the main combustion chamber 3 through the small hole in the middle and lower part; then, a large flow of propellant is sprayed into the main combustion chamber 3 through the main injector 2, and ignited under the action of the high-temperature combustion gas, and the high-temperature combustion gas generated by all the propellants is ejected supersonically through the engine nozzle 4, thereby generating a reaction thrust. In a preferred example, a heating annular heating element is also provided on the branch injector 11, and the heating annular heating element is in contact with the igniter 12. The igniter 12 does not directly ignite the non-toxic propellant in the branch injector 11, but ignites the atomized small droplets by means of the heating annular heating element.

[0046] Embodiment 2: Embodiment 2 is a preferred embodiment

[0047] The present invention is further described below by taking a 40N graded non-catalytic ignition non-toxic monopropellant engine as an example.

[0048] In this embodiment, an electric heat ignition scheme is used to ignite the branch propellant; the branch injector 11 is equipped with a branch injection core, and the small flow rate propellant is atomized into small droplets under the action of the branch injection core; the propellant flow rate passing through the branch injector 11 is 12% of the total flow rate; after the electric heat igniter 12 is energized, the annular heating element placed in the branch combustion chamber 131 is heated to above 500°C, and the atomized propellant droplets are ignited by thermal decomposition after contacting the high-temperature heating element;

[0049] The branch injector 11 is made of titanium alloy, the branch cavity 13 is made of niobium alloy, the length of the branch cavity 13 is 50 mm, of which the length inserted into the combustion chamber is 40 mm, and multiple rows of small holes are processed in the range of 3 to 37 mm in height from the bottom;

[0050] The main injector 2 is equipped with a main injection core 22, and the main large flow rate propellant is atomized into small droplets under the action of the main injection core 22 by the impact atomization method. The main injector is made of titanium alloy material, and 6 groups of impact pairs are processed on the injection core, with an impact angle of 90° and an impact synthesis angle of 0°.

[0051] The main combustion chamber 3 is 100 mm long, has a chamber pressure of 2.5 MPa, and is made of niobium alloy. The main combustion chamber 3 is connected to the main injector 2 by electron beam welding. The engine nozzle 4 is a Laval nozzle, which is connected to the main combustion chamber 3 by electron beam welding.

[0052] The present invention also provides a spacecraft, which adopts the staged non-catalytic ignition non-toxic single-component engine.

[0053] In order to realize the non-catalytic ignition and operation of a non-toxic monopropellant engine with greater thrust, the present invention adopts a non-toxic monopropellant engine with staged ignition. Staged ignition means first using a certain amount of energy to ignite a small amount of propellant in the branch, and then using the high-temperature combustion gas generated by the branch to ignite the main propellant, thereby realizing reliable ignition of a non-toxic monopropellant engine with greater thrust. The present invention realizes the output of a larger thrust of the engine through staged ignition; the present invention does not adopt a conventional catalytic ignition scheme, which can greatly save the cost of precious metal catalysts and can achieve a higher specific impulse performance of the engine. The present invention adopts a staged non-catalytic ignition scheme, which can overcome the problem that large-flow non-toxic monopropellant is difficult to ignite, and can achieve an output of tens of Newtons, hundreds of Newtons or even greater thrust of the engine; and the engine adopts a non-catalytic ignition scheme, without the use of precious metal catalysts, which can save the cost of expensive catalysts, and can circumvent the problems of catalyst temperature resistance limitation and the difficulty of self-control of precious metal raw materials.

[0054] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0055] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A staged non-catalytic ignition non-toxic monopropellant engine, It is characterized in that It comprises a branch ignition module (1), a main injector (2), a main combustion chamber (3) and an engine nozzle (4); The main injector (2) and the engine nozzle (4) are respectively installed at two ends of the main combustion chamber (3); The branch ignition module (1) is coaxially arranged with the main combustion chamber (3), and the end of the branch ignition module (1) is located in the main combustion chamber (3); a plurality of through holes (14) are provided in the middle and lower part of the branch ignition module (1); and the middle and lower part of the branch ignition module (1) is connected with the main combustion chamber (3) through the through holes (14); The branch ignition module (1) comprises a branch injector (11), an igniter (12) and a branch cavity (13), wherein the branch injector (11) is installed at one end of the branch cavity (13), the igniter (12) is installed in the branch cavity (13), and the other end of the branch cavity (13) is defined as a branch combustion chamber (131); The branch combustion chamber (131) is provided with a plurality of through holes (14); The branch injector (11) comprises a branch injector core, and the branch injector core is used to atomize the non-toxic propellant in the branch injector (11) into liquid droplets; The non-toxic propellant in the branch injector (11) is atomized into liquid droplets by the branch injector core, and then ignited by the igniter (12) to become high-temperature combustion gas, which flows into the main combustion chamber (3) through the through hole (14); The main injection device (2) comprises a main injection housing (21), a main injection core (22) and a pressure measuring nozzle (23); The main injection core (22) and the pressure measuring nozzle (23) are both mounted on the injection housing (21); the main injection core (22) is used to atomize the non-toxic propellant in the main injector (2) into liquid droplets; The non-toxic propellant in the main injector (2) enters from the main injection housing (21), is atomized into liquid droplets under the action of the main injection core (22), and is sprayed into the main combustion chamber (3).

2. The staged non-catalytic ignition non-toxic monopropellant engine according to claim 1, It is characterized in that The flow rate of the non-toxic propellant passing through the branch injector (11) is 1 to 30% of the total flow rate of the non-toxic propellant in the staged non-catalytic ignition non-toxic monopropellant engine.

3. The staged non-catalytic ignition non-toxic monopropellant engine according to claim 1, It is characterized in that The igniter (12) is one of electric heat ignition, electrode ignition, laser ignition, torch ignition, and chemical self-ignition ignition.

4. The staged non-catalytic ignition non-toxic monopropellant engine according to claim 1, It is characterized in that The plurality of through holes (14) are arranged in an array along the circumference and radial directions of the branch combustion chamber (131).

5. The staged non-catalytic ignition non-toxic monopropellant engine according to claim 1, It is characterized in that The branch injector (11) and the main injector (2) are made of a material selected from the group consisting of a titanium alloy, an iron-based deformable high-temperature alloy, a nickel-based deformable high-temperature alloy, a cobalt-based deformable high-temperature alloy, and stainless steel.

6. The staged non-catalytic ignition non-toxic monopropellant engine according to claim 1, It is characterized in that The branch cavity (13) and the main combustion chamber (3) are made of one of niobium alloy, molybdenum alloy, platinum-rhodium alloy, platinum-iridium alloy, iridium-rhodium alloy, rhenium-iridium alloy, tungsten-rhenium alloy or tantalum-tungsten alloy.

7. The staged non-catalytic ignition non-toxic monopropellant engine according to claim 1, It is characterized in that The non-toxic propellant is one or a mixture of several of hydroxylamine nitrate (HAN) based propellants, ammonium dinitramide (ADN) based propellants and hydrazine nitrate (HNF) based propellants.

8. A spacecraft, It is characterized in that A staged non-catalytic ignition non-toxic monocomponent engine is used as described in any one of claims 1 to 7.

Images