阅读说明：本技术 一种超燃冲压发动机的燃料掺混装置 (Fuel mixing device of scramjet engine ) 是由 田野 钟富宇 杨顺华 李季 时文 肖保国 鲁玲 李世豪 孙光焱 张娜 于 2020-07-03 设计创作，主要内容包括：本发明专利公开了一种超燃冲压发动机的燃料掺混装置,具体涉及超燃冲压发动机的技术领域。一种超燃冲压发动机的燃料掺混装置,包括发动机本体和位于发动机本体内的凹槽,所述发动机本体上设有位于凹槽内的燃料喷注块,所述燃料喷注块上开有多个圆形的第一喷孔,所述发动机本体内还设有位于凹槽一侧的射流空气喷注块,所述射流空气喷注块上开有多个圆形的第二喷孔,所述射流空气喷注块上设有与第二喷孔连通的金属软管,所述金属软管上连接有储气瓶。采用本发明技术方案克服了现有的超燃冲压发动机无法在不改几何构型的情况下促进燃料混合的问题,可用于提高超燃冲压发动机的燃料和空气的混合效率。(The invention discloses a fuel mixing device of a scramjet engine, and particularly relates to the technical field of scramjet engines. The utility model provides a scramjet engine's fuel mixing device, includes the engine body and is located this internal recess of engine, be equipped with the fuel that is located the recess on the engine body and spout the notes piece, it has a plurality of circular shape first orifices to open on the fuel spouts the notes piece, this internal jet air that still is equipped with in recess one side spouts the notes piece, it has a plurality of circular shape second orifices to open on the jet air spouts the notes piece, be equipped with the metal collapsible tube with the second orifice intercommunication on the jet air spouts the notes piece, the last gas bomb that is connected with of metal collapsible tube. The technical scheme of the invention solves the problem that the existing scramjet engine can not promote fuel mixing under the condition of not changing the geometric configuration, and can be used for improving the mixing efficiency of the fuel and air of the scramjet engine.)

1. A fuel blending device of a scramjet engine is characterized in that: the engine comprises an engine body and a groove located in the engine body, wherein a fuel injection block located in the groove is arranged on the engine body, a plurality of circular first spray holes are formed in the fuel injection block, a jet air injection block located on one side of the groove is further arranged in the engine body, a plurality of circular second spray holes are formed in the jet air injection block, a metal hose communicated with the second spray holes is arranged on the jet air injection block, and a gas storage bottle is connected to the metal hose.

2. The fuel blending device of a scramjet engine of claim 1, wherein: the metal hose is provided with an electromagnetic valve.

3. The fuel blending device of a scramjet engine of claim 1, wherein: the distance between the jet air injection block and the groove is 5-20% of the whole length of the engine.

4. The fuel blending device of a scramjet engine of claim 1, wherein: the jet air flow of all the second nozzle holes is 20% of the engine body inlet flow.

5. The fuel blending device of a scramjet engine according to any one of claims 1 to 4, wherein: an O-shaped sealing ring is arranged between the jet air injection block and the engine body.

Technical Field

The invention relates to the technical field of scramjet engines, in particular to a fuel blending device of a scramjet engine.

Background

The combustion process of the scramjet engine is complex and often comprises fuel injection, atomization, evaporation, mixing, ignition, stable combustion and the like. The flowing time of fuel in the scramjet engine is often in the millisecond order, fuel mixing is an important influence factor for realizing engine starting ignition and stable combustion, if the fuel and air cannot be sufficiently mixed, the scramjet engine cannot realize reliable ignition, and particularly stable combustion generates positive thrust. Although the optimum mixing of the fuel is to achieve the correct ratio of fuel to air for chemical reaction, it is often not practical to achieve, or only locally, so it is the most appropriate method and conventional means to promote as much fuel mixing as possible so that the fuel mixing equivalence ratio is close to the chemically correct ratio.

The conventional fuel enhancement mixing methods such as special-shaped spray holes, slope injection and the like are more frequently used, and the aim is to enhance the penetration depth of the fuel. However, the above technical means often change the ideal configuration of the scramjet engine, and bring about a certain performance loss, so that there is an urgent need for a scramjet engine which can enhance fuel mixing without changing the geometric configuration of the scramjet engine.

Disclosure of Invention

The invention aims to provide a fuel blending device of a scramjet engine, which aims to solve the problem that the existing scramjet engine cannot promote fuel mixing under the condition of not changing the geometric configuration.

In order to achieve the purpose, the technical scheme of the invention is as follows: the utility model provides a scramjet engine's fuel mixing device, includes the engine body and is located this internal recess of engine, be equipped with the fuel that is located the recess on the engine body and spout the notes piece, it has a plurality of circular shape first orifices to open on the fuel spouts the notes piece, this internal jet air that still is equipped with in recess one side spouts the notes piece, it has a plurality of circular shape second orifices to open on the jet air spouts the notes piece, be equipped with the metal collapsible tube with the second orifice intercommunication on the jet air spouts the notes piece, the last gas bomb that is connected with of metal collapsible tube.

The principle and the effect of the technical scheme are as follows: when the engine is used, air is sprayed into the engine body through the air storage bottle and the jet air spraying block, and a blocking effect is generated on supersonic air in the engine body by means of the air (namely, the jet air is perpendicular to incoming flow, the back pressure of the downstream of the incoming flow is increased, or the air flow channel is narrowed to cause blocking), so that the flow field structure in the engine body is changed, and a shock wave string structure is generated. Under the combined action of the shock wave string, the wall boundary layer of the engine body and the shear layer at the lower part of the groove, the wall boundary layer of the engine body is separated, and the shear layer at the lower part of the groove is lifted into the main flow of the engine body, so that the increase of the vorticity in a flow field is realized, the efficient mixing of injected fuel and air in an injection block is promoted, and the aim of enhancing the fuel mixing efficiency on the premise of not changing the injection method of the fuel or the geometric configuration of the engine is realized.

Furthermore, an electromagnetic valve is arranged on the metal hose. The automatic air injection can be realized by means of the electromagnetic valve, and the working efficiency is improved.

Further, the distance between the jet air injection block and the groove is 5% -20% of the whole length of the engine. Through the arrangement, the shock wave string generated by the jet flow can influence the groove, and the efficiency of fuel blending is facilitated.

Further, the jet air flow of all the second nozzle holes is 20% of the engine body inlet flow. Through the arrangement, the mixing effect of the engine can be greatly improved.

Furthermore, an O-shaped sealing ring is arranged between the jet air injection block and the engine body. The sealing ring can realize the sealing when the jet air injection block is connected with the engine body, ensure the relative flow of the air in the engine body and the external ambient air Wu, and is convenient for the disassembly and the installation of the jet air injection block.

Drawings

FIG. 1 is a schematic structural diagram of a fuel blending device of a scramjet engine according to the present embodiment;

FIG. 2 is a cross-sectional view of a fuel blending device of a scramjet engine according to the present embodiment;

FIG. 3 is a flow field shading of the rear expansion section of the groove after the air jet is implemented in this embodiment;

FIG. 4 is a graph comparing the pressure distribution on the inner wall surface of the engine block with and without the air jet in the present embodiment;

FIG. 5 is an ethylene fuel iso-surface distribution plot for the present example with and without air injection;

FIG. 6 is a cross-sectional profile of ethylene fuel with and without air jets implemented in this example;

FIG. 7 is a graph comparing the mixing efficiency of the scramjet engine with and without the air jets implemented in this example.

Detailed Description

The present invention will be described in further detail below by way of specific embodiments:

reference numerals in the drawings of the specification include: the fuel injection device comprises an engine body 1, a groove 2, a fuel injection block 3, a first nozzle hole 4, a jet air injection block 5 and a second nozzle hole 6.