A sealing device and method based on a bifurcation and merging resistance enhancement mechanism

Abstract

This invention provides a sealing device and method based on a bifurcation and confluence resistance-increasing mechanism. The device includes a return ring and a toothed ring. The return ring is a stationary component with multiple stages of return channels; the toothed ring is a rotating component with multiple stages of inclined teeth. The method involves the return channels guiding the bifurcation flow into a reverse jet, which converges with the forward airflow at the top of the teeth, thereby improving local dissipation and flow resistance. This invention provides a novel sealing device with higher sealing efficiency, simple structure, high reliability, and wide application range.

Description

Technical Field

[0001] This invention belongs to the field of aero-engines and gas turbines, and particularly relates to a sealing device and method based on a bifurcation and confluence resistance-increasing mechanism. Background Technology

[0002] Improving sealing efficiency is crucial for reducing air consumption in air systems, preventing combustible gas intrusion, and enhancing the efficiency of aero-engines and gas turbines. Existing sealing devices mainly include: grating seals, brush seals, and fingertip seals. Grating seals are non-contact seals, offering advantages such as simple structure and stable performance, but their sealing efficiency needs improvement. Brush seals and fingertip seals are contact seals, offering higher sealing efficiency, but their complex structures and the risk of erosion pose a challenge. To meet the requirements of next-generation aero-engines and gas turbines, there is an urgent need to develop a non-contact sealing device that is simple in structure, stable in performance, and offers higher sealing efficiency. Summary of the Invention

[0003] To address the problems of existing technologies, this invention provides a sealing device and method based on a bifurcation and confluence resistance-increasing mechanism. By separating the bifurcation flow and gradually converging it with the main flow, the local dissipation and flow resistance are increased, thereby significantly improving the sealing efficiency.

[0004] This invention provides a sealing device based on a bifurcation and confluence resistance-increasing mechanism, which has a simple structure, including a return ring and a toothed ring; the return ring and the toothed ring are inner and outer rings, and there is a gap between the return ring and the toothed ring; the return ring is a stationary component; the toothed ring is a rotating component.

[0005] The return loop has N levels of return channels, with a channel width of [missing information]. d 3. The inlet and outlet angles of the channel are respectively α 1 and α 2. The distance between the entrance and exit of the passage is d 1. N takes the value of a natural number.

[0006] The toothed ring has N levels of teeth, and the tooth inclination angle is... β The distance between adjacent teeth is d 2. The gap between the teeth is d 4.

[0007] The number of return channels is the same as the number of grates, and the outlet of the return channel is directly opposite the top of the grates; the width of the return channel... d 3 is less than the gap between the teeth. d 4; the distance between the inlet and outlet of the return channel d 1 is less than the distance between adjacent teeth. d 2. Furthermore, the inlet of the return channel is far from the outlet of the previous channel.

[0008] The inlet angle of the return channelα 1 is greater than or equal to the exit angle α 2. The inlet and outlet directions of the channel are towards the high-voltage inlet.

[0009] The grating teeth are inclined towards the high-pressure inlet.

[0010] In one embodiment of the present invention, the device is used in a centrifugal compressor, and the device further includes a stator casing and an impeller;

[0011] The return ring is connected to the stator casing by bolts;

[0012] The toothed ring is tightly connected to the adjacent rotating bladed disk; the adjacent rotating bladed disk refers to the impeller;

[0013] The reflux ring, the toothed ring, and the stator housing form a chamber, and the reflux ring and the stator housing are connected to each other by bolts.

[0014] In another embodiment of the present invention, the device is used in the interstage of an axial turbine, and the device further includes a front-stage turbine bladed disk, a stator guide vane, and a rear-stage turbine bladed disk;

[0015] The reflux ring is connected to the stator guide vane by bolts;

[0016] The toothed ring is tightly connected to the adjacent rotating bladed disk; the adjacent rotating bladed disk refers to the front turbine bladed disk and the rear turbine bladed disk;

[0017] The stator guide vane and the preceding turbine bladed disk form a chamber, which is a high-pressure chamber;

[0018] The stator guide vane and the subsequent turbine disk form a chamber, which is a low-pressure chamber.

[0019] The present invention also provides a sealing method for a bifurcation and busbar resistance-increasing mechanism, comprising the following steps:

[0020] Step 1: After the high-pressure airflow enters the device, the bifurcation stream separates from the main stream and enters the first-stage return channel. After the bifurcation stream flows out of the first-stage return channel, it forms a reverse jet in the opposite direction to the main stream and merges with the main stream at the top of the corresponding grate tooth.

[0021] Step 2: The bifurcation stream is separated from the main stream and enters the second-level return channel, repeating the process in Step 1.

[0022] The advantages of this invention are: 1. It proposes a novel non-contact sealing device based on the bifurcation and confluence resistance increase mechanism; 2. It has a simple structure, high reliability, and long service life; 3. It has higher sealing efficiency. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of a sealing device based on a bifurcation and confluence resistance-increasing mechanism.

[0025] Figure 2 This is a schematic diagram of a sealing device in a centrifugal compressor based on a bifurcation and confluence resistance-increasing mechanism.

[0026] Figure 3 This is a schematic diagram of a sealing device based on a bifurcation and confluence resistance-increasing mechanism in the interstage of an axial turbine.

[0027] Figure 4 This is a velocity cloud diagram inside the toothed sealing device.

[0028] Figure 5 This is a velocity contour map inside the sealing device based on the bifurcation and confluence resistance increase mechanism.

[0029] Figure 6 This is a diagram showing the velocity vector distribution within the toothed sealing device.

[0030] Figure 7 This is a velocity vector distribution diagram within a sealing device based on a bifurcation and confluence resistance-increasing mechanism.

[0031] Figure 8 A pie chart used to leak traffic.

[0032] The labels in the diagram indicate the following: 1. Return ring; 2. Grate ring; 3. Stator casing; 4. Bolt; 5. Fore-stage turbine disk; 6. Stator guide vane; 7. After-stage turbine disk; 11. Return channel; 21. Grate; 22. Impeller. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] like Figure 1 The image shows a sealing device based on a bifurcation and confluence resistance-increasing mechanism proposed in an embodiment of the present invention, including a return ring 1, a toothed ring 2, a return channel 11, and teeth 21.

[0035] The return ring 1 and the grate ring 2 are in an inner and outer circular relationship, and there is a gap of 0.2~0.5mm between the return ring 1 and the grate ring 2; the return ring 1 is a stationary component, and the return ring 1 is connected to the stator casing or stator guide vane by bolts; the grate ring 2 is a rotating component, and the grate ring 2 is tightly connected to the adjacent rotating blade disk.

[0036] The return ring 1 is provided with multiple return channels, the channel width being... d 3. The entrance and exit angles of the passage are respectively α 1 and α 2. The distance between the entrance and exit of the passage is d 1.

[0037] The toothed ring 2 has multiple levels of teeth, and the tooth inclination angle is... β The distance between adjacent teeth is d 2. The gap between the teeth is d 4.

[0038] Furthermore, the number of return channels is the same as the number of grates, and the channel outlets are directly opposite the tops of the grates; the width of the return channels... d 3. The gap between the teeth must be smaller than the gap between the teeth. d 4; the distance between the inlet and outlet of the return channel d 1. The distance between adjacent teeth must be less than the distance between the teeth. d 2. Furthermore, it should be ensured that the inlet of the return channel is far from the outlet of the preceding channel; the inlet angle of the return channel... α 1. The outlet inclination angle shall not be less than the outlet angle. α 2; The inlet and outlet of the return channel and the inclined direction of the grating teeth should both face the high-pressure inlet and must not be reversed.

[0039] The sealing device based on the bifurcation and merging resistance increase mechanism proposed in this invention can be applied to multiple scenarios, such as... Figure 2 The diagram shows a sealing device based on a bifurcation and confluence resistance-increasing mechanism in a centrifugal compressor. In this embodiment, the centrifugal compressor structure includes a reflux ring 1, a grate ring 2, a stator casing 3, bolts 4, a reflux channel 11, grates 21, and an impeller 22.

[0040] A chamber is formed between the return ring 1, the toothed ring 2, and the stator casing. Reducing the leakage flow rate of the chamber helps to improve the efficiency of the centrifugal compressor.

[0041] The return ring 2 and the stator casing 3 are connected to each other by bolts 4.

[0042] like Figure 3 The diagram shows a sealing device based on a bifurcation and confluence drag-increasing mechanism between axial turbine stages. In this embodiment, the axial turbine structure includes a return ring 1, a grate ring 2, a front turbine disk 5, a stator guide vane 6, a rear turbine disk 7, a return channel 11, and grates 21.

[0043] The stator guide vane 6, together with the front turbine disk 5 and the rear turbine disk 7, form a chamber, wherein the front chamber is a high-pressure chamber and the rear chamber is a low-pressure chamber.

[0044] The return ring 1 and the toothed ring 2 form a sealing device based on the bifurcation and confluence resistance-increasing mechanism, which prevents interstage airflow leakage and improves turbine efficiency.

[0045] Furthermore, an application example illustrates the gain effect of the sealing device based on the bifurcation and busbar resistance enhancement mechanism. In this example, the return ring has four return channels, with a channel width of... d 3 is 0.5mm, channel inlet angle α 1 and the exit angle α Both are 30°, the distance between the entrance and exit of the passage. d 1 is 6mm; the grate ring has 4 levels of grates, and the grate inclination angle is 6mm. β The angle is 45°, and the spacing between adjacent teeth is... d 2 is 8mm, gap between the teeth d 4 represents 0.6 mm. Furthermore, for comparison, the embodiment also includes a grate sealing device without a return ring, whose grate parameters are the same as those of the sealing device based on the bifurcation and confluence resistance-increasing mechanism. The total inlet pressure of the sealing device is 202650, and the total outlet pressure is 101325, corresponding to a pressure drop ratio of 2. The grate ring rotation speed is 9000 rpm.

[0046] The above parameters are modeled and simulated to obtain... Figure 4 Velocity cloud diagram inside the toothed sealing device Figure 5 Velocity contour map inside the sealing device based on the bifurcation and confluence resistance increase mechanism. Figure 6 Velocity vector distribution diagram inside the toothed sealing device Figure 7 Velocity vector distribution diagram within the sealing device based on the bifurcation and merging resistance enhancement mechanism, where... Figure 4 and Figure 5 Velocity refers to speed. In traditional toothed sealing devices, the airflow flows step by step, with density decreasing along the path and velocity increasing accordingly, forming vortices between the teeth. In sealing devices based on a bifurcation and confluence drag-increasing mechanism, the return channel separates the airflow and forms a reverse jet, causing a significant reduction in the maximum velocity within the device. Meanwhile, the vortices between the teeth move upwards, and the main flow adheres closely to the tooth wall to the next tooth.

[0047] like Figure 8 The image shows a pie chart of leakage flow rates. Under the parameters of this embodiment, the leakage flow rate of the toothed sealing device is 0.194 kg / s, while the leakage flow rate of the sealing device based on the bifurcation and confluence resistance-increasing mechanism is 0.159 kg / s. Compared with the toothed sealing device, the sealing device based on the bifurcation and confluence resistance-increasing mechanism has an efficiency improvement of 18.04%.

[0048] This invention provides a sealing device and method based on a bifurcation and confluence resistance-increasing mechanism. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment of the invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A sealing device based on a bifurcation and merging resistance-increasing mechanism, characterized in that, It includes a reflux ring and a grate ring; the reflux ring and the grate ring are inner and outer rings, and there is a gap between the reflux ring and the grate ring; the reflux ring is a stationary component; the grate ring is a rotating component; The return loop has N levels of return channels, and the width of each return channel is [missing information]. d 3. The inlet and outlet angles of the reflux channel are respectively α 1 and α 2. The distance between the inlet and outlet of the return channel is d 1. N takes the value of a natural number; The toothed ring has N levels of teeth, and the tooth inclination angle is... β The distance between adjacent teeth is d 2. The gap between the teeth is d 4; The number of return channels is the same as the number of grates, and the outlet of the return channel is directly opposite the top of the grates; the width of the return channel... d 3 is less than the gap between the teeth. d 4; the distance between the inlet and outlet of the return channel d 1 is less than the distance between adjacent teeth. d 2. Furthermore, the inlet of the return channel is far from the outlet of the previous channel.

2. A sealing device based on a bifurcation and merging resistance-increasing mechanism according to claim 1, characterized in that, The inlet angle of the return channel α 1 is greater than or equal to the exit angle α 2. The inlet and outlet directions of the return channel are oriented towards the high-pressure inlet.

3. A sealing device based on a bifurcation and merging resistance-increasing mechanism according to claim 2, characterized in that, The grating teeth are inclined towards the high-pressure inlet.

4. A sealing device based on a bifurcation and merging resistance-increasing mechanism according to claim 3, characterized in that, The device is used in a centrifugal compressor, and the device also includes a stator casing and an impeller; The return ring is connected to the stator casing by bolts; The toothed ring is tightly connected to the adjacent rotating bladed disk; the adjacent rotating bladed disk refers to the impeller; A chamber is formed between the reflux ring, the toothed ring, and the stator casing.

5. A sealing device based on a bifurcation and merging resistance-increasing mechanism according to claim 3, characterized in that, The device is used in the interstage of an axial turbine, and the device also includes a front turbine bladed disk, a stator guide vane, and a rear turbine bladed disk. The reflux ring is connected to the stator guide vane by bolts; The toothed ring is tightly connected to the adjacent rotating bladed disk; the adjacent rotating bladed disk refers to the front turbine bladed disk and the rear turbine bladed disk; The stator guide vane and the preceding turbine bladed disk form a chamber, which is a high-pressure chamber; The stator guide vane and the subsequent turbine disk form a chamber, which is a low-pressure chamber.

6. A sealing method based on the bifurcation and merging resistance-increasing mechanism implemented by the device as described in any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1: After the high-pressure airflow enters the device, the bifurcation stream separates from the main stream and enters the first-stage return channel. After the bifurcation stream flows out of the first-stage return channel, it forms a reverse jet in the opposite direction to the main stream and merges with the main stream at the top of the corresponding grate tooth. Step 2: The bifurcation stream is separated from the main stream and enters the second-level return channel, repeating the process in Step 1.

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