A turbopump

Abstract

The present application relates to the technical field of fluid sealing, in particular to a turbine pump with a mechanical seal composite open-cell foam medium sealing ring, comprising a dynamic ring and a static ring of mechanical seal, the dynamic ring is uniformly distributed with flush holes from the ring bottom surface to the outer diameter side in the circumferential direction, the outer diameter side of the dynamic ring and the static ring is provided with an annular channel, and the flush holes and the annular channel of the dynamic ring and the static ring are embedded with foam medium. The sealing ring improves the structure of the turbine pump mechanical seal ring by embedding open-cell foam medium, strengthens the heat transfer of the sealing end face, and reduces the end face temperature.

Description

[0001] This application is a divisional application of application number 2023107904222, application date June 30, 2023, and invention title "A composite perforated foam medium sealing ring for a turbine pump mechanical seal and a turbine pump". Technical Field

[0002] This invention relates to the field of fluid sealing technology, and specifically to a turbine pump employing a mechanical seal composite open-cell foam medium sealing ring. Background Technology

[0003] The turbopump is a core component of a rocket engine, and the mechanical seal, as a crucial component of the turbopump, plays a vital role in its performance. Under actual operating conditions, the mechanical seal rotates at high speed, generating significant frictional and viscous shear heat on the sealing ring end face. Combined with the heat generated by stirring, this leads to excessively high end face temperatures, causing a series of problems such as thermal deformation, liquid film vaporization, and thermal cracking. Therefore, to ensure the reliability of the turbopump, higher requirements are placed on the turbopump mechanical seal. Currently, using novel sealing ring structures has become an effective approach to researching mechanical seals.

[0004] Qiu et al. (DOI: 10.1115 / 1.4006063) established a three-dimensional thermohydrodynamic model of a mechanical seal with a U-shaped notch, and conducted a detailed analysis of the thermal mixing and heat transfer characteristics within the U-shaped notch. They also discussed the heat transfer path and cooling mechanism of the notch. Zhang Weizheng et al. (DOI: 10.11949 / 0438-1157.20221377) established a three-dimensional thermohydrodynamic lubrication model of a composite end-face configuration of annular and spiral grooves, analyzed the influence of groove geometry parameters on the temperature field and sealing performance under both models, and revealed the influence mechanism of flow state on the cooling effect of the end-face grooves. Both of these studies essentially reduce the end-face temperature by changing the shape of the sealing end face, but they are still traditional processing methods. Although they have a certain cooling effect, it is not significant. Summary of the Invention

[0005] The purpose of this invention is to provide a composite open-cell foam medium sealing ring for a turbine pump mechanical seal and a turbine pump. The sealing ring improves the structure of the turbine pump mechanical seal ring by embedding open-cell foam medium, enhances heat transfer at the sealing end face, and reduces the end face temperature.

[0006] The technical solution of the present invention is as follows: a composite open-pore foam medium sealing ring for a turbine pump mechanical seal, comprising a dynamic ring and a stationary ring of the mechanical seal, wherein flushing holes are uniformly distributed in the circumferential direction of the dynamic ring, extending from the bottom surface of the ring to the outer diameter side, and annular grooves are provided on the outer diameter side of both the dynamic ring and the stationary ring, wherein foam medium is embedded in the flushing holes and the annular grooves of the dynamic ring and the stationary ring.

[0007] Furthermore, the annular groove of the moving ring is disposed between the flushing hole and the end face that mates with the stationary ring, and the annular groove of the stationary ring is disposed between the bottom surface of the stationary ring and the end face that mates with the moving ring.

[0008] Furthermore, the structure of the flushing hole is an "L"-shaped straight hole, a "one"-shaped oblique hole, or a curved hole; the cross-sectional shape of the flushing hole is square, circular, or polygonal.

[0009] Furthermore, the diameter of the flushing hole is selected from 2 to 6 cm, and the number of holes is selected from 8 to 30; the axial height of the annular channel is 1 to 10 mm, and the radial depth is 1 to 8 mm.

[0010] Furthermore, the foam medium is an open-cell foam metal material or an open-cell foam non-metal material.

[0011] Furthermore, the open-cell foam metal material is foamed copper, foamed aluminum, or foamed nickel; the open-cell foam non-metal material is foamed graphite or foamed ceramic. Furthermore, the porosity of the open-cell foam medium is selected in the range of 50% to 97%, and the pore density is selected in the range of 10 PPI to 95 PPI.

[0012] Furthermore, the foam medium between the flushing holes and the annular channel is connected by pressure fixing, bonding or brazing.

[0013] Furthermore, the mechanical seal of the turbopump can be a contact mechanical seal or a non-contact mechanical seal.

[0014] A turbopump, comprising the aforementioned turbopump mechanical seal composite open-pore foam medium sealing ring.

[0015] Compared with the prior art, the present invention has the following advantages: 1. This sealing ring, using an open-cell foam medium, is embedded within the flushing hole and between the grooves of the "tooth" structure of the rotating and stationary rings. This effectively improves the mechanical seal ring structure of the turbopump, enhances convective heat transfer between the sealing medium and the ring end face, and reduces the end face and liquid film temperature. It overcomes a series of problems in existing turbopump mechanical seals during high-speed rotation, such as thermal deformation, liquid film vaporization, and thermal cracking at the end faces of the rotating and stationary rings.

[0016] 2. This sealing ring utilizes the advantages of open-cell foam material, such as large specific surface area, good permeability, strong turbulence effect, and high heat transfer efficiency, which greatly reduces the heat generated by friction and fluid viscous shear, thereby significantly extending the service life of the mechanical seal of the turbine pump.

[0017] 3. This sealing ring can be used in both contact turbine pump mechanical seals and non-contact turbine pump mechanical seals. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the present invention. Figure 2 This is a schematic diagram of the "L"-shaped flushing hole on the moving ring of the present invention; Figure 3 This is a schematic diagram of a straight hole with an angle greater than 90 degrees on the moving ring of the present invention; Figure 4 This is a schematic diagram of the oblique hole in the moving ring of the present invention. Figure 5 This is a schematic diagram of the circular bent hole on the moving ring of the present invention; Figure 6 This is a schematic diagram of an open-cell foam medium structure with a specific porosity according to the present invention. Figure 7 This is a schematic diagram of an open-cell foam medium structure with another porosity according to the present invention; Figure 8 This is a schematic diagram of the double-layer open-cell foam medium structure of the present invention; In the diagram: A-moving ring, B-stationary ring, 1-bottom surface of the ring, 2-outer diameter side, 3-"L" shaped flushing hole, 4-annular channel, 5-foam medium, 6-straight hole with an angle greater than 90 degrees, 7-"I" shaped oblique hole, 8-circular bend. Detailed Implementation

[0019] To make the above features and advantages of the present invention more readily understood, specific embodiments are described below in conjunction with the accompanying drawings, but the present invention is not limited thereto.

[0020] refer to Figures 1 to 8 A composite perforated foam medium sealing ring for a turbine pump mechanical seal includes a rotating ring A and a stationary ring B. The rotating ring has flushing holes evenly distributed circumferentially, extending from the bottom surface 1 of the ring to the outer diameter side 2. Both the rotating and stationary rings have annular channels 4 forming a tooth-like structure on their outer diameter sides. Foam medium 5 is embedded within the flushing holes and the annular channels of the rotating and stationary rings. When the rotating ring rotates at high speed, driven by the centrifugal force of the fluid, the low-temperature medium in the sealing cavity flows in from the openings on the bottom surface of the rotating ring, ensuring full contact between the sealing medium and the foam material, and then flows back into the sealing cavity from the openings on the outer diameter side. Simultaneously, the high-speed rotation of the rotating ring draws the sealing medium to flow outside the rotating and stationary rings, allowing the low-temperature sealing medium to enter the foam material. Because the foam material has advantages such as large specific surface area, good permeability, strong turbulence effect, and high heat transfer efficiency, it greatly improves the sealing ring structure, enhances the convective heat transfer between the sealing medium and the ring end face, and reduces the temperature of the sealing ring end face.

[0021] In this embodiment, the annular groove of the moving ring is disposed between the flushing hole and the end face that mates with the stationary ring, and the annular groove of the stationary ring is disposed between the bottom surface of the stationary ring and the end face that mates with the moving ring.

[0022] In this embodiment, the flushing hole has an "L"-shaped straight hole (see reference). Figure 2 ), "one-line" oblique hole (reference) Figure 3 ) or bend (see reference) Figure 5 It can also be a straight hole at other angles (see reference). Figure 4 The cross-sectional shape of the flushing hole can be square, circular, polygonal, or other shapes.

[0023] In this embodiment, the diameter of the flushing hole is selected from 2 to 6 cm, and the number of holes is selected from 8 to 30.

[0024] In this embodiment, the axial height of the annular channel is 1-10mm and the radial depth is 1-8mm.

[0025] In this embodiment, the foam medium is an open-cell foamed metal material, such as foamed copper, foamed aluminum, or foamed nickel. The foam medium can also be an open-cell foamed non-metallic material, such as foamed graphite or foamed ceramic.

[0026] In this embodiment, the porosity of the open-cell foam medium is selected in the range of 50% to 97%, and the pore density is selected in the range of 10 PPI to 95 PPI.

[0027] In this embodiment, the foam medium in the flushing hole and the foam medium in the annular channels of the moving ring and stationary ring are connected to the annular surface by pressure fixing, bonding or brazing.

[0028] In this embodiment, the mechanical seal of the turbopump can be a contact mechanical seal or a non-contact mechanical seal.

[0029] Working Principle: When the rotating ring of the turbine pump mechanical seal rotates at high speed, driven by the centrifugal force of the fluid, the low-temperature medium in the sealing cavity flows in from the opening on the bottom surface of the rotating ring. After fully contacting the foam material, it flows back into the sealing cavity from the opening on the outer diameter side. Simultaneously, the rotation of the rotating ring pulls the medium in the sealing cavity to flow outside the rotating and stationary rings, allowing the low-temperature sealing medium to enter the foam material. The foam material has a large specific surface area, good permeability, strong turbulence effect, and high heat transfer efficiency, enhancing the convective heat transfer between the sealing medium and the ring end face, thereby reducing the temperature of the sealing ring end face. Compared with similar hydrodynamic mechanical seal structures, the mechanical seal structure of this invention significantly reduces the heat generated by friction and fluid viscous shear, thus greatly extending the service life of the turbine pump mechanical seal.

[0030] A turbopump, comprising the aforementioned turbopump mechanical seal composite open-pore foam medium sealing ring.

[0031] The above description is only a preferred embodiment of the present invention. For those skilled in the art, designing different forms of composite open-cell foam medium sealing rings for turbine pump mechanical seals based on the teachings of the present invention does not require creative labor. All equivalent changes, modifications, substitutions, and variations made in accordance with the scope of the patent application of the present invention without departing from the principles and spirit of the present invention shall be covered by the present invention.

Claims

1. A turbopump, comprising a mechanical seal composite open-cell foam medium sealing ring, characterized in that, The mechanical seal composite open-pore foam medium sealing ring includes a rotating ring and a stationary ring. The rotating ring has flushing holes evenly distributed circumferentially from its bottom surface to its outer diameter. The diameter of the flushing holes ranges from 2 to 6 cm, and the number of holes ranges from 8 to 30. Both the rotating and stationary rings have annular grooves on their outer diameter sides. The axial height of these grooves is 1-10 mm, and the radial depth is 1-8 mm. Foam medium is embedded within the flushing holes and the annular grooves of the rotating and stationary rings. The annular groove of the rotating ring is located between the flushing hole and the end face that mates with the stationary ring, and the annular groove of the stationary ring is located between the bottom surface of the stationary ring and the end face that mates with the rotating ring. The foam medium between the flushing holes and the annular grooves is connected by pressure fixing, bonding, or brazing.

2. A turbine pump according to claim 1, characterized in that, The structure of the flushing hole is an "L"-shaped straight hole, a "one"-shaped oblique hole, or a curved hole; the cross-sectional shape of the flushing hole is square, circular, or polygonal.

3. A turbine pump according to claim 1, characterized in that, The foam medium is an open-cell foam metal material or an open-cell foam non-metal material.

4. A turbine pump according to claim 3, characterized in that, The open-cell foam metal material is copper foam, aluminum foam, or nickel foam.

5. A turbine pump according to claim 3, characterized in that, The open-cell foam non-metallic material is foamed graphite or foamed ceramic.

6. A turbine pump according to claim 5 or 6, characterized in that, The porosity of the open-cell foam medium is selected in the range of 50% to 97%, and the pore density is selected in the range of 10 PPI to 95 PPI.

7. A turbine pump according to claim 1, characterized in that, The mechanical seal of the turbo pump can be a contact mechanical seal or a non-contact mechanical seal.

Images