CN106989931B

CN106989931B - High-frequency pulse injection device

Info

Publication number: CN106989931B
Application number: CN201710364402.3A
Authority: CN
Inventors: 高宏力; 刘祺; 邓维鑫; 杨顺华
Original assignee: Southwest Jiaotong University
Current assignee: Southwest Jiaotong University
Priority date: 2017-05-22
Filing date: 2017-05-22
Publication date: 2023-04-25
Anticipated expiration: 2037-05-22
Also published as: CN106989931A

Abstract

The invention provides a high-frequency pulse injection device, and relates to the technical field of ramjet engines. The method can effectively solve the technical problem of rapid mixing of the incoming flow of the engine. The end head at the upper part of the transmission shaft is matched with the square blind hole at the bottom of the rotary disk and is fixed by a screw; the upper part of the main structure body is of a cavity structure, the top end of the main structure body is provided with a rotary disk with an axial through hole, the middle part of the cavity and the bottom surface of the rotary disk form an annular channel, the center of the lower part of the cavity is provided with a through shaft hole, the left side of the cavity is provided with an axial oil filling hole connected with the annular channel, and the transmission shaft is positioned in the shaft hole below the main structure body; the first injection through holes are uniformly distributed on two circumferences along the radial direction of the injection disk, and the second injection through holes are uniformly distributed on circumferences along the radial direction of the rotary disk and equal to the injection through holes on the injection disk. The method is mainly used for rapid mixing of the incoming flow of the engine.

Description

High-frequency pulse injection device

Technical Field

The invention relates to the technical field of ramjet engines.

Background

The incoming flow rate of a scramjet engine is very fast, and the residence time of the fuel tends to be in the order of milliseconds, and for liquid hydrocarbon fuels, the droplet break-up, atomization and vaporization processes are also considered, which all increase the time and the length of the combustion chamber required for the fuel to achieve a complete chemical reaction. The length of the combustion chamber cannot be long due to the limitations of the engine structure, mass, etc., and thus, it is difficult to achieve complete mixing of fuel with the incoming flow. Supersonic combustion is typically diffusion flame, and the blending effect directly determines the combustion performance of the combustion chamber. Thus, fuel injection and blending techniques have been key technologies in scramjet engine research.

The fuel injection technology commonly used in current scramjet engines is divided into passive blending enhancement and active blending enhancement. The passive blending enhancement is relatively widely applied at present, and mainly comprises modes of physical slopes, concave cavities, tower structures and the like, and mainly has the following problems: (1) Macroscopic turbulence can be achieved, but microscopic turbulence is not sufficient to achieve a high degree of mixing of fuel with incoming flow; (2) The mixing of fuel and incoming flow has a relatively long process, and the requirements are difficult to meet; (3) It is difficult to control the influence of the pressure increase due to heat release. Thus, active blending enhancement techniques based on various large scale forced excitations are also a popular research direction for blending enhancement techniques. Research and development of a high-frequency pulse injection device as an effective fuel injection and blending technology is particularly necessary to effectively realize the mixing of fuel and incoming flow at the molecular level.

Disclosure of Invention

The invention aims to provide a high-frequency pulse injection device which can effectively solve the technical problem of rapid mixing of incoming flows of an engine.

The aim of the invention is realized by the following technical scheme: the high-frequency pulse injection device comprises a main structure body and a transmission shaft, wherein the transmission shaft is connected with a servo motor through a coupler, a square end head is arranged at the upper part of the transmission shaft, and the end head is matched with a square blind hole at the bottom of a rotating disk and is fixed through a screw; the top end of the main structure body is provided with a spray disc which is fixed through four bolts uniformly distributed on the circumference, the upper part of the main structure body is of a cavity structure, the upper part of the cavity is provided with a rotary disc with axial through holes, the middle part of the cavity and the bottom surface of the rotary disc form an annular channel, the center of the lower part of the cavity is provided with a through shaft hole, the left side is provided with an axial oil filling hole connected with the annular channel, the circumference lower part of the outer diameter of the rotary disc is provided with a first O-shaped sealing ring, the lower end surface of the rotary disc is provided with a second O-shaped sealing ring, and the transmission shaft is positioned in the shaft hole below the main structure body; the first injection through holes are uniformly distributed on two circumferences along the radial direction of the injection disk, and the second injection through holes are uniformly distributed on circumferences along the radial direction of the rotary disk and equal to the injection through holes on the injection disk.

The hole diameters of all the injection holes distributed on the same circumference are the same; the holes distributed on different circumferences, the aperture of the through hole of the inner ring is smaller than that of the through hole of the outer ring, and the through holes are in direct proportion to the diameters of the circumferences distributed by the through holes.

The injection holes uniformly distributed on the two circumferences of the injection disk (5) are staggered one by one.

And the number of the holes of the injection through holes II uniformly distributed on the rotating disk on a single circumference is an integral multiple of 2 or 4.

And the hole axes of the injection through holes II uniformly distributed on the rotating disk are positioned on radial lines which are concentrically radiated.

The upper end face of the rotating disc is provided with concentric grooves.

And two O-shaped sealing rings III are arranged in the middle of the transmission shaft.

The main structure body is provided with an oil filling hole which enables the oil supply pipeline to be communicated with the cavity inside the device.

The working process and principle of the invention are as follows: the oil supply pipeline is connected with the oil filling hole, and fuel is injected into the cavity in the device at high pressure through the oil filling hole. The external servo motor drives the transmission shaft to rotate at a certain rotation speed through the coupler, and the transmission shaft transmits torque to the rotating disc through the cooperation of the square end head at the end part of the transmission shaft and the square blind hole in the center of the bottom of the rotating disc, so that the rotating disc can rotate at a certain speed. The rotation of the rotary disk enables the injection through holes on the rotary disk to be periodically communicated or closed with the injection through holes on the injection disk at a certain frequency, so that the pulse injection of fuel is realized, and the pulse frequency and the injection quantity of the fuel injection are greatly different due to the difference of the hole numbers, the hole diameters and the rotary disk rotation speed of the injection disk and the rotary disk.

Compared with the prior art, the invention has the beneficial effects that: improves the prior fuel injection and blending technology,

1. the invention has the advantages of small volume, simple structure, low processing difficulty, stable and reliable structure, meets the use requirement of severe working conditions, has better interchangeability of parts and is easy to maintain and maintain as a whole.

2. The invention effectively realizes the pulse injection of fuel and can realize the accurate control of the rotating speed of the rotating disc, thereby realizing the control of the injection frequency and the injection quantity of the fuel.

Furthermore, the invention specially designs the distribution form of the injection through holes: the two-circumference distribution mode of the injection through holes on the injection disk and the rotary disk is adopted, the hole diameters of all the injection through holes distributed on the same circumference are the same, the holes distributed on different circumferences are smaller than the hole diameter of the outer ring through hole, and the hole diameters of the inner ring through holes are in direct proportion to the diameters of the circumferences distributed by the through holes.

Thus, the pulse frequency can reach 10 when the device injects fuel ⁴ The Hz order of magnitude better satisfies the fuel injection requirement of the scramjet engine, realizes the high mixing of fuel and incoming flow, and does not cause too dense distribution of injection through holes on the same circumference to achieve the required injection frequency, thereby influencing the strength of the injection disk or the rotating disk.

Secondly, the proportional relation of the apertures ensures that the time length of each injection pulse is kept consistent, and good pulse characteristics in the fuel injection process are realized. The injection device has the advantages of small volume, simple structure, easy maintenance and easy maintenance, can provide high-frequency pulse fuel injection flow, fully mixes the pulse fuel injection flow with the incoming flow of the aircraft, and meets the combustion requirement of the scramjet engine.

Drawings

FIG. 1 is an exploded view of the overall structure of an embodiment of the present invention;

FIG. 2 is a cross-sectional view of the assembled structure of an embodiment of the present invention;

FIG. 3 is an enlarged view at E in FIG. 2;

fig. 4 is an isometric cutaway view of a primary structure.

Detailed Description

The invention is described in further detail below with reference to the drawings and the detailed description.

1-4, one specific implementation of the present invention is: a high-frequency pulse injection device comprises a transmission shaft 1 connected with a servo motor and a coupler, wherein the transmission shaft 1 is connected with an injection device structure body,

the structure body of the injection device comprises an injection disc 5 and a main structure body 2 which are connected and fixed through bolts uniformly distributed on the circumference, and a cavity is formed in the structure. The rotary disk 9 is placed in the cavity, and elastic deformation is caused by the compression action of the first O-shaped sealing ring 4 on the lower part of the outer diameter surface and the second O-shaped sealing ring 3 on the end surface of the bottom, so that the rotary disk 9 is tightly attached to the injection disk 5; the square block end of the transmission shaft 1 is fixedly connected with the rotary disk 9 through a screw 7, and two O-shaped sealing rings three 11 for rods are arranged at the contact part of the transmission shaft 1 and the through hole in the center of the lower part of the main structure body 2.

The injection disk 5 of this example has an equal number of injection through holes 6 uniformly distributed on two different circumferences, and the number of holes on a single circumference is an integer multiple of 4. The injection holes 6 distributed on the two circumferences do not exist on the same radial line of the injection disk 5 at the same time, namely, the injection holes 6 on the two circumferences are distributed in a staggered way.

The rotary disk 9 of this example has equal amounts of injection through holes 8 distributed on two different circumferences, the number of holes on a single circumference can be an integer multiple of 2 or 4, the number of holes of the injection disk 5 is not required to be equal, and the axes of two 8 holes of the injection through holes distributed on the two circumferences are positioned on the same radial line of the rotary disk 9. The end face of one side of the rotary disk 9, which is contacted with the injection disk 5, is provided with a groove concentric with the rotary disk, and the center of the end face of the other side is provided with a square blind hole matched with the square end of the transmission shaft 1.

All the injection through holes in the embodiment have the same hole diameter, the through holes are distributed on the same circumference, the hole diameters of the through holes in the inner ring are smaller than the hole diameters of the through holes in the outer ring, and the hole diameters of the through holes are in direct proportion to the diameters of the circumferences on which the through holes are distributed.

The main structure 2 of this example is provided with an axial oil filler hole 10, and the oil filler hole 10 communicates an oil supply pipe with an internal cavity of the device.

Claims

1. The utility model provides a high frequency pulse injection device, includes main structure body (2) and transmission shaft (1), and transmission shaft (1) are connected its characterized in that with servo motor through the shaft coupling: the upper part of the transmission shaft (1) is provided with a square end head which is matched with a square blind hole at the bottom of the rotary disk (9) and is fixed by a screw (7); the top end of the main structure body (2) is provided with an injection disk (5) which is fixed through four bolts uniformly distributed on the circumference, the upper part of the main structure body (2) is of a cavity structure, the upper part of the cavity structure is provided with a rotary disk (9) with an axial through hole, the middle part of the cavity and the bottom surface of the rotary disk (9) form an annular channel, the center of the lower part of the cavity is provided with a through shaft hole, the left side is provided with an axial oil filling hole (10) connected with the annular channel, the circumference lower part of the outer diameter of the rotary disk (9) is provided with an O-shaped sealing ring I (4), the lower end surface of the rotary disk (9) is provided with an O-shaped sealing ring II (3), and the upper end surface of the rotary disk (9) is provided with concentric grooves; the transmission shaft (1) is positioned in a shaft hole below the main structure body (2); injection through holes I (6) are uniformly distributed on two circumferences along the radial direction of the injection disk (5), injection through holes II (8) are uniformly distributed on circumferences along the radial direction of the rotary disk (9) which are equal to the injection through holes I (6) on the injection disk (5), and the hole axial lines of the injection through holes II (8) uniformly distributed on the rotary disk (9) are positioned on radial lines of concentric radiation; the axial oil filling hole (10) enables the oil supply pipeline to be communicated with a cavity structure at the upper part of the main structure body (2); the hole diameters of the first injection through holes (6) and the second injection through holes (8) which are distributed on the same circumference are the same; the holes distributed on different circumferences, the aperture of the through hole of the inner ring is smaller than that of the through hole of the outer ring, and the through holes are in direct proportion to the diameters of the circumferences distributed by the through holes.

2. A high frequency pulse jet apparatus as defined in claim 1, wherein: the first spraying holes (6) uniformly distributed on two circumferences of the spraying disc (5) are staggered.

3. A high frequency pulse jet apparatus as defined in claim 1, wherein: the number of holes on the circumference of the injection through holes II (8) uniformly distributed on the rotating disc (9) is an integral multiple of 2.

4. A high frequency pulse jet apparatus as defined in claim 1, wherein: two O-shaped sealing rings III (11) are arranged in the middle of the transmission shaft (1).