Compressor casing device with narrow front and wide rear slot

Abstract

The present invention discloses a compressor casing device with a narrow front and wide rear type, the device comprising: a hub for mounting a rotor; a rotor, composed of a plurality of blades rotating around a rotation axis, mounted on the hub; a cylindrical test piece casing, having a set thickness and surrounding the blades at 360°; a plurality of slit-type processing casings, each of which is discretely opened on the inner wall of the cylindrical test piece casing at a set spacing. The compressor casing device with a narrow front and wide rear type disclosed by the present invention has a plurality of discrete inclined slits opened on the inner wall of the test piece casing, and the slits are inclined at a certain angle toward the direction of rotation of the rotor. The slit presents a linear expansion design with a narrow front and wide rear from the direction of airflow flow. Through the pressure difference between the upper and lower streams of the bottom surface of the slit, the slit draws low-energy fluid from the blade tip, and then transports it to the upstream for injection, thereby changing the momentum of the blade tip leakage flow and the mainstream, and improving the flow loss. The effect of taking into account both the efficiency and expansion stability of the compressor is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of compressor flow stability control, and in particular to a compressor casing device with a narrow front and wide rear slot. Background Art

[0002] Compressor stability is one of the most important parameters to measure compressor performance, and its quality directly affects the safety of the engine and the pilot. The slotted casing has attracted much attention due to its strong stability expansion capability. The slotted casing can improve the flow blockage in the compressor blade tip area, delay the occurrence of factors causing compressor instability, and thus improve the stall margin of the compressor. The flow in the compressor blade tip area has extremely strong three-dimensional flow and unsteady characteristics, and the introduction of the slotted casing intensifies the interaction between the casing and the mainstream. How to design the slotted casing structure to effectively improve the stable operating range of the compressor and reduce the negative impact on the compressor efficiency is still a challenging problem in the current compressor field. Summary of the invention

[0003] The object of the present invention is to provide a compressor casing processing device with a narrow front and wide rear slot, so as to at least partially solve the problems in the background technology.

[0004] The technical solution provided by the present invention is: a compressor casing treatment device with a narrow front and wide rear slot, the device comprising:

[0005] A hub for mounting the rotor;

[0006] The rotor, which is composed of a plurality of blades rotating around a rotation axis, is mounted on the hub;

[0007] A cylindrical test piece casing having a set thickness and surrounding the blade at 360°;

[0008] A plurality of slot-type processing casings are discretely arranged on the inner wall of the cylindrical test piece casing with a set spacing between each slot-type processing casing.

[0009] In some embodiments, the axial overlap between the opening of the slotted processing casing and the blade tip of the rotor is 0.4-1.0 times the axial chord length of the blade tip.

[0010] In some embodiments, the ratio of the middle width of the bottom surface of the slot type processing casing to the spacing between the processing casings is less than 0.6, and the spacing between the processing casings = the middle width of the bottom surface of the slot type processing casing + the set spacing between two adjacent slot type processing casings.

[0011] In some embodiments, the height of the slotted processing casing is less than 0.5 times the axial chord length of the blade tip of the rotor.

[0012] In some embodiments, the length of the slotted processing casing is 0.5-1.0 times the axial chord length of the rotor blade tip.

[0013] In some embodiments, the inclination angle of the slotted processing casing to the rotation direction of the rotor is less than or equal to 60°.

[0014] In some embodiments, the inclination angle of the slotted processing casing toward the rotation axis of the rotor is less than or equal to 90°.

[0015] In some embodiments, the slotted processing case has a single blade passage number of less than or equal to 10 on the rotor.

[0016] In some embodiments, the slot-type processing casing is a linear expansion structure that is narrow in the front and wide in the rear along the airflow direction.

[0017] In some embodiments, the cross-section of the slotted processing casing is rectangular, arc-shaped or streamlined.

[0018] In some embodiments, the set spacing between each slot processing magazine is the same.

[0019] In some embodiments, a tip clearance is provided between the rotor and the cylindrical test article casing.

[0020] In some embodiments, the compressor is a single-stage or multi-stage axial flow, mixed flow or radial flow compressor.

[0021] Compared with the prior art methods, the compressor casing treatment device with narrow front and wide rear slot type proposed by the present invention has the following advantages:

[0022] The slot-type treatment casing structure with a narrow front and wide rear type, while ensuring that the opening area of ​​the slot-type treatment casing remains unchanged, has a larger suction area due to its wide rear design, so that more low-energy fluid in the blade tip area can be sucked into the slot, reducing blade tip blockage. At the same time, the suction effect can greatly weaken the development of the blade tip leakage vortex and reduce the blade tip leakage, reducing leakage loss and mixing loss. On the other hand, the transportation effect of the slot ejects the downstream low-energy fluid upstream under the action of the pressure difference. Its narrow front design can make the fluid injection speed higher, accelerate the incoming flow, so that the incoming flow obtains a greater momentum, and "resist" the overflow of the leakage flow. Therefore, this design can effectively improve the stable operating range of the compressor without causing large losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solution provided by the present invention, the following is a brief introduction to the accompanying drawings. The following accompanying drawings are only some embodiments of the present invention.

[0024] Figure 1It is a schematic diagram of the meridian structure of a slot-type processing casing according to an embodiment of the present invention;

[0025] Figure 2 for Figure 1 Structural diagram of the AA section in;

[0026] Figure 3 for Figure 1 Structural diagram of the BB section in;

[0027] Figure 4-Figure 8 Meridian structural diagrams of slot-type processing casings in various cross-sectional forms when implementing the present invention.

[0028] In the figure:

[0029] 1-Wheel Hub

[0030] 2-Cylindrical test piece casing

[0031] 3-Rotor

[0032] 4-slot handling receiver DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the following is a detailed description of the present invention in conjunction with the accompanying drawings and through specific embodiments. It should be noted that the implementation methods not described in the accompanying drawings are forms known to technicians in the relevant technical field. The directional terms mentioned in the following embodiments are only reference to the directions of the accompanying drawings. Therefore, the directional terms used are for explanation and are not intended to limit the present invention.

[0034] An embodiment of the present invention provides a compressor casing treatment device with a narrow front and wide rear slot, such as Figure 1 As shown, including:

[0035] A hub 1, which is used to install the rotor 3, specifically, to install and fix the blades on the rotor 3;

[0036] A rotor 3, which is composed of a plurality of blades rotating around a rotation axis and is mounted on the hub 1 and is used to perform work on the working medium;

[0037] The cylindrical test piece casing 2 has a set thickness and surrounds the blades on the rotor 3 at 360 degrees;

[0038] A plurality of slot-type processing cases 4 are discretely opened on the inner wall of the cylindrical test piece case 2 with a set interval between each slot-type processing case 4 .

[0039] In some embodiments, there is a tip gap between the compressor rotor 3 and the cylindrical test piece casing 2. Under the action of the pressure difference between the tip pressure surface and the suction surface of the compressor rotor 3, the airflow passes through the gap to form a leakage flow, which thickens the end wall boundary layer and aggravates the flow blockage, causing the compressor to stall.

[0040] In some embodiments, a plurality of evenly distributed slot-type processing cases 4 are provided on the inner wall of the cylindrical test case 2 of the compressor, that is, the set spacing between each slot-type processing case 4 is made the same. This structure can suck the low-energy fluid accumulated on the blade tip, and through the transportation action of the slot-type processing case 4, the fluid is ejected upstream, mixed with the incoming flow to accelerate the incoming flow, so that the incoming flow obtains a higher flow momentum, hinders the overflow of the leakage flow, and delays the occurrence of stall.

[0041] In some embodiments, the seam-type processing casing further comprises:

[0042] The length of the slotted treatment casing is 0.5-1.0 times the axial chord length of the rotor blade tip; and / or

[0043] The height of the slotted treatment casing is less than 0.5 times the axial chord length of the rotor blade tip; and / or

[0044] The axial overlap between the opening of the slot-type processing casing and the blade tip of the rotor is 0.4-1.0 times the axial chord length of the blade tip.

[0045] In this embodiment, Figure 1 As shown, the length L of the slotted processing casing 4 is 80% of the axial chord length of the blade tip; the height H of the slotted processing casing 4 is 25% of the axial chord length of the blade tip; and the axial overlap O between the opening of the slotted processing casing 4 and the blade tip of the rotor is 40% of the axial chord length of the blade tip.

[0046] In some other embodiments, for the above-mentioned seam-type processing casing, there are further:

[0047] The inclination angle of the slotted treatment casing toward the rotation axis of the rotor is less than or equal to 90°; and / or

[0048] The inclination angle of the slotted treatment casing to the rotation direction of the rotor is less than or equal to 60°; and / or

[0049] The number of single blade channels of the rotor of the slotted processing casing is less than or equal to 10.

[0050] In this embodiment, Figure 2 and Figure 3 As shown, the angle α between the slot-type processing casing 4 and the rotation axis direction is 30°; the number of slot-type processing casings 4 in each blade channel is 4; and the inclination angle θ of the slot-type processing casing 4 to the rotation direction of the rotor 3 is 30°.

[0051] In this embodiment, based on the above-mentioned seam-type processing casing 4, it further includes:

[0052] See also Figure 3 In the cross section BB shown, the bottom surface of the slot-type processing casing 4 follows the direction of airflow, and the bottom surface of the slot-type processing casing 4 shows a linear widening trend from front to back;

[0053] See also Figure 3 In the BB section shown, the relative position of the rotating compressor rotor 3 and the slotted processing casing 4 will change periodically. When the slotted processing casing 4 is located directly above the compressor rotor 3, the bottom surface of the slotted processing casing 4 just spans the pressure surface and the suction surface of the compressor rotor 3. Under the action of the pressure difference between the pressure surface and the suction surface, the low-energy fluid gathered at the blade tip will be sucked into the slotted processing casing 4, then transported upstream, and then injected into the incoming flow, mixed with the incoming flow, accelerating the incoming flow, and increasing the flow momentum of the incoming flow. Therefore, the slotted processing casing 4 can effectively reduce the blockage in the blade tip area and enable the incoming flow to obtain a higher momentum to improve the flow of the blade tip, thereby improving the stable operating range of the compressor.

[0054] In some other embodiments, the seam-type processing casing further includes:

[0055] The ratio of the middle width of the bottom surface of the slit type processing casing to the spacing between the processing casings is less than 0.6, and the spacing between the processing casings = the middle width of the bottom surface of the slit type processing casing + the set spacing between two adjacent slit type processing casings.

[0056] The cross-section of the slotted processing receiver is rectangular, arc-shaped or streamlined, such as Figure 4-Figure 8 shown.

[0057] In summary, the above-mentioned multiple parameters of the slotted processing casing 4 can be optimized according to the air intake of the application object to more effectively improve the stability of the compressor and reduce the negative impact on the compressor efficiency.

[0058] In some embodiments, the compressor formed by the slotted processing casing with different parameters can be a single-stage or multi-stage axial flow, mixed flow or radial flow compressor.

[0059] The above descriptions are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the present invention.

[0060] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A compressor casing treatment device with narrow front and wide rear slots, characterized in that: include: A hub for mounting the rotor; The rotor is composed of a plurality of blades rotating around a rotation axis and is mounted on the hub; A cylindrical test piece casing having a set thickness and surrounding the blade at 360°; A plurality of slot-type processing cases are discretely arranged on the inner wall of the cylindrical test piece case with a set spacing between each slot-type processing case. The slot-type processing cases are in a linear expansion structure with a narrow front and a wide rear along the airflow direction.

2. The compressor casing treatment device with narrow front and wide rear slot type according to claim 1, characterized in that: The axial overlap between the opening of the slot-type processing casing and the blade tip of the rotor is 0.4-1.0 times the axial chord length of the blade tip.

3. The compressor casing treatment device with narrow front and wide rear slot type according to claim 1, characterized in that: The ratio of the middle width of the seam bottom surface of the seam type processing casing to the spacing between the processing casings is less than 0.6, and the spacing between the processing casings = the middle width of the seam bottom surface of the seam type processing casing + the set spacing between two adjacent seam type processing casings.

4. The compressor casing treatment device with narrow front and wide rear slot type according to claim 1, characterized in that: The height of the slotted processing casing is less than 0.5 times the axial chord length of the blade tip of the rotor; and / or The length of the slotted processing casing is 0.5-1.0 times the axial chord length of the blade tip of the rotor.

5. The compressor casing treatment device with narrow front and wide rear slot type according to claim 1, characterized in that: The inclination angle of the slotted processing casing to the rotation direction of the rotor is less than or equal to 60°; and / or The inclination angle of the slot-type processing casing toward the rotation axis direction of the rotor is less than or equal to 90°.

6. The compressor casing treatment device with narrow front and wide rear slot type according to claim 1, characterized in that: The number of the single blade passages of the rotor in the slotted processing casing is less than or equal to 10.

7. The compressor casing treatment device with narrow front and wide rear slot type according to claim 1, characterized in that: The cross section of the slot-type processing casing is rectangular, arc-shaped or streamlined.

8. The compressor casing treatment device with narrow front and wide rear slot type according to claim 1, characterized in that: The set spacings between the respective slot-type processing casings are the same.

9. The compressor casing treatment device with narrow front and wide rear slot type according to claim 1, characterized in that: There is a blade tip clearance between the rotor and the cylindrical test piece casing.

10. The compressor casing treatment device with narrow front and wide rear slot type according to claim 1, characterized in that: The compressor is a single-stage or multi-stage axial flow, mixed flow or radial flow compressor.

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