CN109668172B

CN109668172B - High-speed fuel blender of controllable pulsation vortex

Info

Publication number: CN109668172B
Application number: CN201811504367.1A
Authority: CN
Inventors: 赵永胜; 杨辉; 张江; 吴军飞
Original assignee: China Academy of Aerospace Aerodynamics CAAA
Current assignee: China Academy of Aerospace Aerodynamics CAAA
Priority date: 2018-12-10
Filing date: 2018-12-10
Publication date: 2020-11-10
Anticipated expiration: 2038-12-10
Also published as: CN109668172A

Abstract

The invention discloses a high-speed fuel blender of controllable pulsation vortex, comprising: the device comprises a Laval nozzle, a mixing flow channel, a vortex generator, a balance cavity and a stepping motor; the laval nozzle and the blending flow channel form a main flow channel; the wall surface of the blender comprises the balance cavity, the balance cavity air inlet hole and the oil inlet hole; the vortex generator comprises the central rotating shaft and the triangular wedge; the stepping motor is connected with the vortex generator through the hinge; the main air forms supersonic speed airflow after being accelerated through the Laval nozzle, and forms vortex under the action of the vortex generator; the balance cavity can prevent the gas of the main runner from overflowing; the attitude of the vortex generator can be controlled by controlling the stepping motor, so that controllable pulsating vortex is formed; fuel oil is injected into the mixing flow channel through the oil inlet hole, so that high-speed mixing with the main flow is realized; the air-blending flows out through the air-blending outlet. The invention greatly improves the mixing efficiency of fuel oil and air.

Description

High-speed fuel blender of controllable pulsation vortex

Technical Field

The invention belongs to the field of fuel oil blenders, and particularly relates to a high-speed fuel oil blender capable of controlling pulsating vortex.

Background

The air suction type engine is the main power form of the existing aerospace craft, and the fuel oil and air mixing technology is one of the key technologies related to the engine. The efficiency of blending directly determines the progress, efficiency and stability of combustion, which in turn determines the performance of the engine. Therefore, design optimization of the fuel blender is critical to air breathing engines.

The fuel oil mixer adopted by the prior air suction type engine mainly has the forms of a swirler, a concave cavity, transverse jet flow, coaxial jet flow and the like. The swirler is mainly applied to an aircraft engine, has higher mixing efficiency, but is relatively complex in design and processing, and is not suitable for fuel oil mixing of a supersonic air suction type engine; the cavity is suitable for mixing fuel oil at low speed and high speed, but the mixing area is small, only exists in the cavity, and can induce the problems of combustion chamber thermoacoustic oscillation and the like; the transverse jet flow does not need a physical structure and has a larger mixing area, but has unsteady property, so that the applicable working condition is limited; coaxial jets are similar to transverse jets and have the advantage of less drag being introduced, but less efficient mixing. In addition, the blender forms can only work under specific working conditions and do not have the characteristics of adjustability and controllability. It is therefore desirable to optimize the form and principles of the blender to improve the design level of the air breathing engine.

Disclosure of Invention

The technical problem solved by the invention is as follows: the defects of the prior art are overcome, the high-speed fuel blender capable of controlling the pulsating vortex is provided, and the blending efficiency and the applicable working condition of the fuel blender are improved by the working mode of the controllable pulsating vortex.

The purpose of the invention is realized by the following technical scheme: a high speed fuel blender of controlled pulsating swirl, comprising: the device comprises a Laval nozzle, a mixing flow channel, a vortex generator, a balance cavity and a stepping motor; the laval nozzle and the blending flow channel form a main flow channel; the wall surface of the blender comprises the balance cavity, the balance cavity air inlet hole and the oil inlet hole; the vortex generator comprises the central rotating shaft and the triangular wedge; the stepping motor is connected with the vortex generator through the hinge; the air-blending flows out through the air-blending outlet.

In the above high-speed fuel blender of controllable pulsating vortex, preferably, a plurality of sets of the vortex generators are radially and uniformly distributed in the blending flow channel, and the number of the stepping motors is consistent with the number of the vortex generators;

in the above high-speed fuel blender of controllable pulsating vortex, preferably, the blender wall surface is provided with a plurality of the balance cavity air inlets and a plurality of the oil inlets; the number ratio of the balance cavity air inlet holes to the oil inlet holes is 0.5;

in the high-speed fuel oil blender capable of controlling the pulsating vortex, preferably, the ratio of the static pressure in the balance cavity to the static pressure in the blending flow channel is 1.1-1.3;

in the high-speed fuel blender capable of controlling the pulsating vortex, preferably, the momentum ratio of the fuel injected from the oil inlet hole to the air in the blending flow channel is 10-100;

in the controllable pulsating vortex high-speed fuel oil blender, preferably, the ratio of the diameter phi a of the air inlet to the diameter phi b of the Laval nozzle is 8-10; the ratio of the diameter phi a of the air inlet to the diameter phi c of the mixing flow channel is 0.9-1.1; the ratio of the diameter phi b of the Laval nozzle to the diameter phi d of the mixed gas outlet is 1.3-2;

in the controllable pulsating vortex high-speed fuel blender, preferably, the ratio of the diameter phi e of the oil inlet hole to the diameter phi f of the air inlet hole of the balance cavity is 0.1-0.3;

in the high-speed fuel blender of controllable pulsating vortex, preferably, the ratio of the length L1 of the blended gas outlet to the diameter Phid of the blended gas outlet is 5-10;

in the high-speed fuel blender of controllable pulsating vortex, the ratio of the length L2 of the triangular wedge to the width L3 of the triangular wedge is preferably 1 to 3; the angle theta of the triangular wedge-shaped block is 20-45 degrees.

And further controlling the amplitude of the vortex generator to enable the outlet position of the oil inlet hole to form a pulsating vortex.

Compared with the prior art, the invention has the following beneficial effects:

the invention greatly shortens the mixing time, improves the mixing efficiency and expands the applicable working condition of the fuel mixer. In order to shorten the mixing time, the front end of the mixer adopts a Laval nozzle design to accelerate main flow air; the vortex generator is designed in the blender, and the wave system structure and the vortex structure of the vortex generator are utilized to enhance the blending of fuel oil and air, so that the blending efficiency is improved; in addition, the invention adopts the stepping motor to control the posture of the vortex generator, thereby further enhancing mixing and expanding applicable working conditions.

Drawings

FIG. 1 is a schematic structural diagram of a controlled pulsating vortex high velocity fuel blender according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a vortex generator according to an embodiment of the present invention.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

FIG. 1 is a schematic structural diagram of a controlled pulsating vortex high velocity fuel blender according to an embodiment of the present invention. As shown in fig. 1, the controlled pulsating vortex high velocity fuel blender comprises: the device comprises a Laval nozzle 1, a mixing flow channel 8, a vortex generator 9, a balance cavity 2 and a stepping motor 3; wherein the content of the first and second substances,

the Laval nozzle 1 and the mixing flow channel 8 form a main flow channel of the fuel mixer; the outlet end of the Laval nozzle 1 is hinged with a vortex generator 9; a balance cavity 2 is arranged in the wall surface 6 of the blender, a stepping motor 3 is arranged in the balance cavity 2 and is connected with a vortex generator 9 through a hinge 10, the posture of the vortex generator 9 is controlled through the stepping motor 3, and the outlet position of an oil inlet 5 forms a pulsating vortex by controlling the amplitude of the vortex generator 9; an oil inlet 5 communicated with a mixing flow channel 8 is arranged on the wall surface 6 of the mixer, fuel oil entering through the oil inlet 5 is mixed with the pulsating vortex, and the obtained mixed gas flows out through a mixed gas outlet 7 arranged behind the mixing flow channel 8.

Fig. 2 is a schematic structural diagram of a vortex generator according to an embodiment of the present invention. As shown in fig. 2, the vortex generator 9 includes a central rotating shaft 11 and triangular wedge blocks 12; the triangular wedge block 12 is a revolving body obtained by revolving a triangle by a certain angle with the bottom side as the centre of revolution and the vertex; the bottom edge is provided with a central rotating shaft 11; a triangular wedge-shaped block 12 is arranged at the outlet end of the laval nozzle 1 through a central rotating shaft 11.

The main air forms supersonic speed air flow after being accelerated through the Laval nozzle 1, and forms vortex under the action of the vortex generator 9; the air pressure in the balance cavity 2 is higher than that of the mixing flow channel 8, so that the gas in the main flow channel can be prevented from overflowing, and the sealing effect is achieved; the attitude of the vortex generator 9 can be controlled by controlling the stepping motor 3, so that controllable pulsating vortex is formed; fuel oil is injected into the mixing flow channel 8 through the oil inlet 5 to realize high-speed mixing with the main flow; the air-entrainment flows out through the air-entrainment outlet 7.

4-8 sets of vortex generators 9 are uniformly distributed in the mixing flow channel 8 in the radial direction, and the number of the stepping motors 3 is consistent with that of the vortex generators 9; 4-6 balance cavity air inlets 4 and 8-12 oil inlets 5 are formed in the wall surface 6 of the blender; the ratio of the static pressure in the balance cavity 2 to the static pressure in the mixing flow channel 8 is 1.1-1.3; the momentum ratio of the fuel injected from the oil inlet 5 to the air in the blending flow channel 8 is 10-100; the ratio of the diameter phi a of the air inlet to the diameter phi b of the Laval nozzle is 8-10; the ratio of the diameter phi a of the air inlet to the diameter phi c of the mixing flow channel is 0.9-1.1; the ratio of the diameter phi b of the Laval nozzle to the diameter phi d of the mixed gas outlet is 1.3-2; the ratio of the diameter phi e of the oil inlet hole to the diameter phi f of the air inlet hole of the balance cavity is 0.1-0.3.

As shown in FIG. 2, the ratio of the length L1 of the outlet of the air-entrainment mixture to the diameter Φ d of the outlet of the air-entrainment mixture is 5 to 10; the ratio of the length L2 of the triangular wedge block to the width L3 of the triangular wedge block is 1-3; the angle theta of the triangular wedge-shaped block is 20-45 degrees.

The above-described embodiments are merely preferred embodiments of the present invention, and general changes and substitutions by those skilled in the art within the technical scope of the present invention are included in the protection scope of the present invention.

The invention has not been described in detail in part of the common general knowledge of those skilled in the art.

Claims

1. A high velocity fuel blender of controlled pulsating swirl flow, comprising: the device comprises a Laval nozzle (1), a mixing flow channel (8), a vortex generator (9), a balance cavity (2) and a stepping motor (3); wherein the content of the first and second substances,

the Laval nozzle (1) and the mixing flow channel (8) form a main flow channel of the fuel oil mixer; the outlet end of the Laval nozzle (1) is hinged with a vortex generator (9); a balance cavity (2) is arranged in the wall surface (6) of the blender, a stepping motor (3) is arranged in the balance cavity (2) and is connected with a vortex generator (9) through a hinge (10), and the posture of the vortex generator (9) is controlled through the stepping motor (3) so as to form controllable pulsating vortex; an oil inlet hole (5) communicated with the mixing flow channel (8) is formed in the wall surface (6) of the mixer, fuel oil entering through the oil inlet hole (5) is mixed with the pulsating vortex, and obtained mixed gas flows out through a mixed gas outlet (7) formed behind the mixing flow channel (8).

2. The controlled pulsating vortex high speed fuel blender of claim 1, wherein: the number of the vortex generators (9) is consistent with that of the oil inlet holes (5), and the vortex generators are uniformly distributed in the circumferential direction; the number of the stepping motors (3) is the same as that of the vortex generators (9).

3. The controlled pulsating vortex high speed fuel blender of claim 1, wherein: a plurality of balance cavity air inlets (4) communicated with the balance cavity are arranged on the wall surface (6) of the blender; balance chamber inlet port (4) with inlet port (5) quantity ratio is 1: 1.

4. the controlled pulsating vortex high speed fuel blender of claim 1, wherein: the ratio of the static pressure in the balance cavity (2) to the static pressure in the mixing flow channel (8) is 1.1-1.3.

5. The controlled pulsating vortex high speed fuel blender of claim 1, wherein: the momentum ratio of the fuel injected from the fuel inlet (5) to the air in the mixing flow channel (8) is 10-100.

6. The controlled pulsating vortex high speed fuel blender of claim 1, wherein: the ratio of the diameter phi a of the air inlet to the diameter phi b of the throat part of the Laval nozzle is 8-10; the ratio of the diameter phi a of the air inlet to the diameter phi c of the mixing flow channel is 0.9-1.1; the ratio of the throat diameter phi b of the Laval nozzle to the outlet diameter phi d of the mixed gas is 1.3-2.

7. The controlled pulsating vortex high speed fuel blender of claim 3, wherein: the ratio of the diameter phi e of the oil inlet hole to the diameter phi f of the balance cavity air inlet hole is 0.1-0.3.

8. The controlled pulsating vortex high speed fuel blender of claim 1, wherein: the ratio of the length L1 of the blended gas outlet to the diameter Φ d of the blended gas outlet is 5 to 10.

9. The controlled pulsating vortex high speed fuel blender of claim 1, wherein: the vortex generator (9) comprises a central rotating shaft (11) and a triangular wedge block (12); the triangular wedge-shaped block (12) is a revolving body which is obtained by revolving a triangle by a certain angle with the bottom side as the revolving center and the top point; the bottom edge is provided with a central rotating shaft (11); the triangular wedge-shaped block (12) is arranged at the outlet end of the Laval nozzle (1) through a central rotating shaft (11).

10. The controlled pulsating vortex high speed fuel blender of claim 9, wherein: the triangular wedge-shaped block is an isosceles triangle wedge-shaped block; the ratio of the waist length L2 of the triangle to the bottom length L3 of the triangle wedge-shaped block is 1-3; the rotation angle theta of the triangular wedge-shaped block is 20-45 degrees.

11. The controlled pulsating vortex high speed fuel blender of claim 1, wherein: the outlet position of the oil inlet hole (5) forms a pulsating vortex by controlling the amplitude of the vortex generator (9).