阅读说明：本技术 一种用于大功率氢氧涡轮泵的阻尼密封装置 (Damping sealing device for high-power hydrogen-oxygen turbine pump ) 是由 黄克松 李小芬 叶小强 沈文金 蒋文山 崔垒 杨文静 周丹洋 金志磊 林奇燕 孙 于 2019-10-09 设计创作，主要内容包括：一种用于大功率氢氧涡轮泵的阻尼密封装置,属于火箭发动机技术领域,包括阻尼密封组件1、密封轴套2；所述阻尼密封组件1安装在外部涡轮泵壳体3上；所述密封轴套2安装在外部转轴4上；所述阻尼密封组件1包括外壳5和内衬6；所述外壳5和内衬6之间采用锥面配合；所述内衬6与密封轴套2形成摩擦副；所述内衬6靠近密封轴套2的内表面设有交错排列的孔；所述内衬6在高压液体的端面设有防旋叶片9。本发明通可以提高节流能力,显著降低密封泄漏率；显著提高转子稳定性。(A damping sealing device for a high-power hydrogen-oxygen turbine pump belongs to the technical field of rocket engines and comprises a damping sealing assembly 1 and a sealing shaft sleeve 2; the damping seal assembly 1 is mounted on an outer turbine pump housing 3; the sealing shaft sleeve 2 is arranged on the external rotating shaft 4; the damping seal assembly 1 comprises an outer shell 5 and an inner liner 6; the shell 5 and the lining 6 are matched by a conical surface; the lining 6 and the sealing shaft sleeve 2 form a friction pair; the inner surface of the lining 6 close to the sealing shaft sleeve 2 is provided with staggered holes; the lining 6 is provided with anti-rotation vanes 9 on the end face of the high-pressure liquid. The invention can improve the throttling capacity and obviously reduce the sealing leakage rate; the stability of the rotor is obviously improved.)

1. A damping sealing device for a high-power hydrogen-oxygen turbine pump is characterized by comprising a damping sealing assembly (1) and a sealing shaft sleeve (2);

the damping seal assembly (1) is mounted on an external turbine pump housing (3); the sealing shaft sleeve (2) is arranged on the external rotating shaft (4); the damping seal assembly (1) comprises an outer shell (5) and an inner liner (6); the outer shell (5) and the inner liner (6) are matched by a conical surface; the lining (6) and the sealing shaft sleeve (2) form a friction pair;

the inner surface of the lining (6) close to the sealing shaft sleeve (2) is provided with staggered holes; the end face of the lining (6) at the high-pressure liquid is provided with an anti-rotation blade (9).

2. The damping sealing device for the high-power hydrogen-oxygen turbine pump as claimed in claim 1, wherein the taper of the conical surface fit between the outer shell (5) and the inner liner (6) is 1-2 °.

3. The damping sealing device for the high-power hydrogen-oxygen turbine pump as claimed in claim 1, wherein the inner lining (6) is provided with round holes (8) which are staggered close to the inner surface of the sealing shaft sleeve (2); the round hole (8) is a flat bottom hole, and the depth h of the round hole (8) is 0.4-1.0 mm; the minimum wall thickness s between two adjacent round holes (8) is 0.3 mm-0.5 mm.

4. The damping seal device for high-power hydrogen-oxygen turbine pump according to claim 1, characterized in that the ratio of the clearance Cs between the inner liner (6) of the damping seal assembly (1) and the seal shaft sleeve (2) to the diameter D of the seal shaft sleeve (2) is 1 x 10^-3～3×10^-3。

5. The damping sealing device for the high-power hydrogen-oxygen turbine pump is characterized in that the number of the anti-rotation blades (9) is even, the anti-rotation blades are uniformly distributed along the circumference of the lining (6), and a flow equalizing groove (10) is formed between two adjacent anti-rotation blades (9).

6. The damping sealing device for the high-power hydrogen-oxygen turbine pump as claimed in claim 5, wherein the thickness b of the anti-rotation blades (9) is 2 mm-3 mm; the depth hc of the anti-rotation blade (9) is 2 mm-3 mm.

7. The damping sealing device for the high-power hydrogen-oxygen turbine pump as claimed in one of claims 1 to 6, wherein the outer casing (5) and the inner lining (6) are welded by brazing or electron beam welding.

8. The damping sealing device for the high-power hydrogen-oxygen turbine pump as claimed in one of claims 1 to 6, wherein the outer casing (5) is made of stainless steel or aluminum alloy material, and the inner lining (6) is made of silver-magnesium-nickel alloy or pure silver material.

9. The damping sealing device for the high-power hydrogen-oxygen turbine pump as claimed in one of claims 1 to 6, wherein the sealing shaft sleeve (2) is made of stainless steel or high-temperature alloy material.

10. The damping sealing device for the high-power hydrogen-oxygen turbine pump as claimed in one of claims 1 to 6, wherein the pressure on two sides of the damping sealing device is not more than 30 MPa.

Technical Field

The invention relates to a damping sealing device for a high-power hydrogen-oxygen turbine pump, and belongs to the technical field of rocket engines.

Background

The oxyhydrogen engine has the advantages of high performance, high reliability, environmental protection and the like. The main aerospace big countries in the world take the main aerospace big countries as the main power system of the high-thrust carrier rocket. The hydrogen-oxygen turbine pump is a core component of the hydrogen-oxygen engine, and the technical level of the hydrogen-oxygen turbine pump is usually reflected by the technical level of the engine.

Compared with a small-thrust engine, the high-thrust or heavy-duty engine turbine pump has extremely high working condition and greatly increased power, for example, the power of a hydrogen turbine pump of a main engine of an aerospace plane reaches megawatt level, and the pressure of an outlet of the pump reaches more than 40 MPa. In order to meet the comprehensive performance requirements of high efficiency, light weight and the like of the turbopump, the heavy turbopump generally adopts a supercritical rotor design, and the working rotating speed of the heavy turbopump exceeds the critical rotating speed, so that the design complexity of the turbopump is increased.

In the internal flow path of the turbine pump, for example, a pump impeller shoulder and between two stages of a multi-stage pump, a radial clearance seal such as a labyrinth seal and a straight hole seal is usually arranged for throttling, so that the volume loss from the inside of the pump is reduced. In order to achieve the efficiency index specified by the system, it is necessary to reduce the seal clearance to reduce the loss of the internal flow path volume in the heavy-duty turbo pump. Supercritical rotors generally have a particularly prominent radial seal gap fluid excitation problem, and when the working rotating speed is close to or reaches twice the first-order critical rotating speed of the rotor, the seal gap fluid generates an excitation force acting on the rotor, the vibration frequency of the seal gap fluid is about half of the rotating speed, and the problem is typical subsynchronous vibration. The vibration energy is large, the vibration energy does not disappear along with the increase of the working rotating speed, the premature failure of a bearing, a seal and some structural parts is easily caused, the reliability of the turbine pump is reduced, the service life of the turbine pump is prolonged, and the turbine pump is a main factor that the rotating equipment cannot run at full load.

The turbine pump radial clearance sealing fluid excitation subsynchronous vibration is an inevitable problem in heavy-load turbine pump development. Besides the rotation, the turbine pump rotor has precession around the support connecting line, and the precession direction is the same as the rotation. From the mechanical analysis, it can be known that the tangential force acting on the rotor in the same direction as the rotor precession direction is generated due to the circumferential flow velocity of the fluid in the radial clearance seal, and the tangential force is increased along with the increase of the circumferential velocity of the fluid in the radial clearance seal, and is expressed as larger cross rigidity and smaller damping of the seal fluid in the rotor dynamics. When the rotor is disturbed, the larger cross rigidity of the sealing fluid is easy to increase the precession amplitude and even cause instability.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the defects of the prior art are overcome, and the damping sealing device for the high-power hydrogen-oxygen turbine pump is provided and comprises a damping sealing assembly and a sealing shaft sleeve; the damping seal assembly is mounted on an outer turbine pump housing; the sealing shaft sleeve is arranged on the external rotating shaft; the damping seal assembly comprises an outer shell and an inner liner; the outer shell and the inner lining are matched by a conical surface; the lining and the sealing shaft sleeve form a friction pair; the inner surface of the lining close to the sealing shaft sleeve is provided with staggered holes; the end face of the lining at the high-pressure liquid is provided with an anti-rotation blade.

The purpose of the invention is realized by the following technical scheme:

a damping sealing device for a high-power hydrogen-oxygen turbine pump comprises a damping sealing assembly and a sealing shaft sleeve;

the damping seal assembly is mounted on an outer turbine pump housing; the sealing shaft sleeve is arranged on the external rotating shaft; the damping seal assembly comprises an outer shell and an inner liner; the outer shell and the inner lining are matched by a conical surface; the lining and the sealing shaft sleeve form a friction pair;

the inner surface of the lining close to the sealing shaft sleeve is provided with staggered holes; the end face of the lining at the high-pressure liquid is provided with an anti-rotation blade.

Preferably, the taper of the conical surface fit between the outer shell and the inner lining is 1-2 degrees.

Preferably, round holes which are arranged in a staggered mode are formed in the inner surface, close to the sealing shaft sleeve, of the lining; the round hole is a flat bottom hole, and the depth h of the round hole is 0.4 mm-1.0 mm; the minimum wall thickness s between two adjacent round holes is 0.3 mm-0.5 mm.

Preferably, the ratio of the clearance Cs between the inner lining of the damping seal assembly and the seal shaft sleeve to the diameter D of the seal shaft sleeve is 1 x 10^-3～3×10^-3。

Preferably, the number of the anti-rotation blades is an even number, the anti-rotation blades are uniformly distributed along the circumference of the lining, and a flow equalizing groove is formed between every two adjacent anti-rotation blades.

Preferably, the thickness b of the anti-rotation blade is 2 mm-3 mm; the depth hc of the anti-rotation blade is 2 mm-3 mm.

Preferably, the shell and the lining are welded by brazing or electron beam welding.

Preferably, the outer shell is made of stainless steel or aluminum alloy materials, and the inner liner is made of silver-magnesium-nickel alloy or pure silver materials.

Preferably, the sealing shaft sleeve is made of stainless steel or high-temperature alloy materials.

Preferably, the pressure on two sides of the damping sealing device does not exceed 30 MPa.

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

at present, in the domestic hydrogen-oxygen engine turbopump, the low-temperature hydrogen and oxygen pump impeller shoulder seal and the seal between multi-stage pumps are mostly labyrinth seal or floating ring seal. The floating ring seal leakage rate is low, but the floating ring cannot provide effective rigidity and damping to the rotor and cannot promote the stability of the rotor system. The labyrinth seal has a high leakage rate, and the seal fluid has low rigidity and damping, sometimes even high cross rigidity, which is not favorable for the stability of the rotor.

Compared with the prior art, the hole type damping seal for improving the roughness of the inner circular surface of the seal adopts the staggered small counter bore structure, so that the throttling capacity can be improved, the seal leakage rate can be obviously reduced, the circumferential flow rate of fluid in a seal gap can be reduced, the fluid rigidity and damping can be improved, the cross rigidity can be reduced, and the stability of a rotor can be obviously improved. To the high-speed, high pressure low temperature oxyhydrogen turbo pump that vibration energy is big, the vibration environment is complicated, the application damping seal can improve the logarithmic decrement, reduces rotor strain energy, restraines rotor vibration energy, compares in labyrinth seal, and the damping seal all has bigger advantage.

Drawings

FIG. 1 is an assembly view of a damping and sealing device of an oxyhydrogen turbine pump;

FIG. 2 is a schematic view of a damping seal assembly;

FIG. 3 is a schematic view of a damping seal assembly gap;

FIG. 4 is a schematic view of a damping seal assembly gap;

FIG. 5 illustrates an arrangement of circular holes on the inner surface of the damping seal;

FIG. 6 is a structural form of a damper seal inlet anti-rotation vane.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.