CN112360631B

CN112360631B - MVG-based internal rotation type air inlet flow control method and device and application thereof

Info

Publication number: CN112360631B
Application number: CN202011250183.4A
Authority: CN
Inventors: 贾要强; 朱守梅; 刘小勇; 李大进; 马力; 李斌
Original assignee: Beijing Power Machinery Institute
Current assignee: Beijing Power Machinery Institute
Priority date: 2020-11-10
Filing date: 2020-11-10
Publication date: 2022-09-27
Anticipated expiration: 2040-11-10
Also published as: CN112360631A

Abstract

The invention relates to an MVG-based inward rotation type air inlet flow control method, and belongs to the technical field of air suction type engine design. In the scheme of the invention, the MVG is arranged at a reasonable position, and the direction of the MVG is the same as the direction of the streamline obtained by tracing the streamline, so that the purposes of simple structure, obvious control effect and no additional flow loss are achieved, a vortex opposite to the direction of a flow vortex generated in an air inlet channel can be generated by utilizing a secondary flow deviating from the main flow direction, and the flow vortex is restrained and eliminated by neutralizing the vortex amount; meanwhile, the scheme can effectively inhibit flow direction vortexes in the flow field when only the bottom plate MVG acts, and the influence on the air flow of the throat can be further reduced. After the top plate MVG is added, the vortex in the control flow field with the bottom plate MVG almost disappears.

Description

MVG-based internal rotation type air inlet flow control method and device and application thereof

Technical Field

The invention belongs to the technical field of design of air-breathing engines, and particularly relates to an MVG-based inward-turning air inlet passage flow control method.

Background

The supersonic air inlet is one of important parts of an air suction type engine, and the performance of the supersonic air inlet has an important influence on the overall performance of the engine. The traditional supersonic air inlet type comprises a binary air inlet, an axisymmetric air inlet, a lateral pressure air inlet and the like, and with the development of the technology, the inward turning air inlet gradually becomes a research hotspot of an air intake device of an air-breathing engine. The inward rotation type air inlet is designed based on a streamline tracing technology, a lip mouth of the inward rotation type air inlet reflects a strong circumferential pressure gradient formed by intersecting a shock wave and a side wall, a flow direction vortex is induced and generated in a boundary layer, the flow direction vortex is continuously developed and strengthened in the process of moving along the downstream, and the inward rotation type air inlet interacts with a shock wave string to cause the nonuniformity and instability of a flow field of an isolation section, so that the nonuniformity and instability become main factors influencing the performance of the air inlet. At present, researchers mainly adopt two methods for controlling the flowing vortex, one method is to remove low-energy vortex by pumping and reduce the size of the flowing vortex; the other method is to change the wave system structure by reconstructing the compression profile in the air inlet channel so as to reduce the circumferential pressure gradient and weaken the strength of the flow direction vortex.

The pumping method has limited control effect on the flow direction vortex, and after control is exerted, a larger vortex area still exists in the channel and certain flow loss can be brought; the profile control method needs to be adjusted on the basis of tracking the profile of the original flow line, changes the aerodynamic characteristics of the air inlet channel, improves the design difficulty of the air inlet channel, and is difficult to eliminate flow direction vortexes.

Disclosure of Invention

Technical problem to be solved

The technical problem to be solved by the invention is as follows: how to design a flow control scheme, realize to the effective control of rotary intake duct flow direction whirlpool through adding MVG to restrain the internal flow of rotary intake duct and flow to the whirlpool, promote intake duct export flow field homogeneity.

(II) technical scheme

In order to solve the technical problem, the invention provides an MVG-based inward turning type air inlet channel flow control method, which is realized by the following steps: inner gyration intake duct lip reflection shock wave and the roof of intake duct wall, the intersecting line circumference equipartition round MVG of bottom plate, the direction is the streamline direction in inviscid flow field, corresponds the position of roof, bottom plate and equipartition semi-circle MVG respectively, is the MVG that corresponds the roof position respectively, corresponds the MVG of bottom plate position.

Preferably, all MVGs use vane-type MVGs.

Preferably, the height of the leading edge of each MVG used is 0.

Preferably, the thickness of each MVG used is different.

Preferably, each MVG employed is of a different length.

Preferably, the trailing edge height of each MVG employed is different.

Preferably, each MVG used is located within the boundary layer, and each MVG is matched for its length and trailing edge height according to the local boundary layer thickness.

Preferably, the value range of the tail edge height of each MVG is 0.4-0.7 times of the thickness of the boundary layer.

The invention also provides a device of the inward turning type air inlet flow control method, which comprises the MVG ring.

The invention also provides application of the device in the technical field of designing of air-breathing engines.

(III) advantageous effects

In the scheme of the invention, the MVG is arranged at a reasonable position, and the direction of the MVG is the same as the direction of the streamline obtained by tracing the streamline, so that the purposes of simple structure, obvious control effect and no additional flow loss are achieved, a vortex opposite to the direction of a flow vortex generated in an air inlet channel can be generated by utilizing a secondary flow deviating from the main flow direction, and the flow vortex is restrained and eliminated by neutralizing the vortex amount; meanwhile, the scheme can effectively inhibit flow direction vortexes in the flow field when only the bottom plate MVG acts, and the influence on the air flow of the throat can be further reduced. After the top plate MVG is added, the vortex in the control flow field with the bottom plate MVG almost disappears.

Drawings

FIGS. 1 and 2 are schematic diagrams of an MVG flow control method according to the present invention;

FIG. 3 is a schematic diagram of a variable length MVG scheme in the present invention;

fig. 4 illustrates the flow control effect achieved by the present invention.

Detailed Description

In order to make the objects, contents, and advantages of the present invention clearer, the following detailed description of the embodiments of the present invention will be made in conjunction with the accompanying drawings and examples.

The idea of the flow control scheme of the invention is that MVGs (miniature vortex generators) are distributed along the streamline direction of a non-viscous flow field, when the flow direction of airflow deviates under the influence of circumferential pressure gradient, the MVGs are bypassed, a vortex opposite to the original movement trend direction is formed in an MVG leeward area, and the vortex existing in the flow field is neutralized, so that the aim of inhibiting or eliminating the flow direction vortex is fulfilled. The key that this scheme played the control action lies in the reverse vortex that the leeward district produced, and MVG thickness is less to the influence of control effect, for reducing the resistance, can reduce by a wide margin under the circumstances of guaranteeing structural strength, and then reduces the influence to the larynx circulation ability.

Based on the above thought, as shown in fig. 1 and fig. 2, the inward turning type intake duct flow control method based on MVG provided by the present invention is implemented by the following method: because the inward turning inlet lip reflection shock wave and the top plate of the wall surface of the inlet channel are crossed at the position of the throat, a circle of MVG is uniformly distributed on the crossed line of the inward turning inlet lip reflection shock wave and the top plate and the bottom plate of the wall surface of the inlet channel in the circumferential direction, the direction is the streamline direction of a non-viscous flow field, half circles of MVG are uniformly distributed at the positions corresponding to the top plate and the bottom plate respectively, the MVG corresponding to the position of the top plate is called as the top plate MVG or called as the throat MVG, and the MVG corresponding to the position of the bottom plate is called as the bottom plate MVG;

the front edge height of the MVG is 0 to reduce the front edge resistance of the MVG, the front edge height of the MVG is used for reducing aerodynamic resistance, the wall surface generates strong shock wave compression to cause loss, when a boundary layer generates circumferential migration under the action of a circumferential pressure gradient and bypasses the MVG, a vortex opposite to the direction of primary secondary flow is generated on the leeward side of the MVG, and therefore a neutralization effect is generated between the reverse vortex and the primary secondary flow in the process of developing along the downstream, the vortex strength in the flow field is weakened, and the uniformity of the flow field is improved.

As shown in fig. 3, all the MVGs in a circle of MVGs are vane-type MVGs, but each MVG has a different thickness, a different length, and a different trailing edge height, and because the MVGs are located in the boundary layer, each MVG matches its length and trailing edge height in combination with the thickness of the local boundary layer to achieve the best control effect, in this embodiment, the value range of the trailing edge height of the MVG is 0.4-0.7 times the thickness of the boundary layer, so as to form a certain leeward space to generate a vortex for flow control.

The invention also provides a device for realizing the flow control method of the inward turning type air inlet channel, namely the circle of MVG.

In the scheme of the invention, the MVG is arranged at a reasonable position, and the direction of the MVG is the same as the direction of the streamline obtained by tracing the streamline, so that the purposes of simple structure, obvious control effect and no additional flow loss are achieved, a vortex opposite to the direction of a flow vortex generated in an air inlet channel can be generated by utilizing a secondary flow deviating from the main flow direction, and the flow vortex is restrained and eliminated by neutralizing the vortex amount; meanwhile, the scheme can effectively inhibit flow direction vortexes in the flow field when only the bottom plate MVG acts, and the influence on the air flow of the throat can be further reduced. As shown in fig. 4 a, the boundary layer of the flow field without MVG control has significant vortex, and after the top plate MVG is added, as can be seen from the MVG control flow field with the bottom plate shown in b, the vortex in the flow path almost disappears, and the streamline in the boundary layer on the side of the top plate of the flow field is linearly distributed. Therefore, the scheme has the advantages of simple structure, small additional resistance, remarkable flow field improvement effect and the like.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. An MVG-based inward rotation type air inlet channel flow control method is characterized by being realized by the following steps: a circle of MVG is uniformly distributed in the circumferential direction of the intersection line of the lip reflected shock wave of the inward turning air inlet channel and the top plate and the bottom plate on the wall surface of the air inlet channel, the direction is the streamline direction of the non-viscous flow field, and the positions corresponding to the top plate and the bottom plate are respectively and uniformly distributed with a half circle of MVG which is respectively the MVG corresponding to the position of the top plate and the MVG corresponding to the position of the bottom plate; all MVGs used vane-type MVGs.

2. The method of claim 1, wherein the height of the leading edge of each MVG used is 0.

3. The method of claim 2, wherein the thickness of each MVG employed is different.

4. The method of claim 3, wherein each MVG employed is a different length.

5. The method of claim 4, wherein the trailing edge height of each MVG employed is different.

6. The method of claim 5, wherein each MVG employed is located within the boundary layer, and each MVG is matched for length and trailing edge height based on local boundary layer thickness.

7. The method of claim 6, wherein the height of each MVG trailing edge is selected to be in the range of 0.4 to 0.7 times the thickness of the boundary layer.

8. An apparatus for implementing the internal turning duct flow control method according to any one of claims 1 to 7, wherein the apparatus includes the ring of MVGs.

9. Use of a device according to claim 8 in the field of air-breathing engine design.