阅读说明：本技术 一种超高转速液氢涡轮泵柔性转子 (Flexible rotor of ultrahigh-rotating-speed liquid hydrogen turbopump ) 是由 李铭 胡晓睿 涂霆 王怡萱 曹耀 赵海龙 李龙 姜绪强 褚宝鑫 于 2020-06-23 设计创作，主要内容包括：本发明涉及一种超高转速液氢涡轮泵柔性转子,包括螺杆(1)、诱导轮(2)、压紧螺母(3)、轴(4)、一级离心轮(5)、金属橡胶阻尼器(6)、鼠笼式弹性支承(7)、轴承对(8)、级间轴套(9)、二级离心轮(10)、平衡活塞(11)、金属橡胶阻尼器挡板(12)、第一轴套(13)、涡轮盘(14)、大螺母(15)、预载碟簧(16)、第二轴套(17)；本发明的柔性转子的轴系双向外伸,优化连接、传扭结构,减轻转子质量,缩短两侧悬臂和支撑跨距,超临界工作,额定转速达到80000rpm,临界转速裕度20％以上,同时具备60％-100％变工况和轴向力自适应平衡能力。(The invention relates to a flexible rotor of an ultrahigh-rotating-speed liquid hydrogen turbopump, which comprises a screw rod (1), an inducer (2), a compression nut (3), a shaft (4), a primary centrifugal wheel (5), a metal rubber damper (6), a squirrel-cage elastic support (7), a bearing pair (8), an interstage shaft sleeve (9), a secondary centrifugal wheel (10), a balance piston (11), a metal rubber damper baffle plate (12), a first shaft sleeve (13), a turbine disc (14), a large nut (15), a preloading disc spring (16) and a second shaft sleeve (17); the flexible rotor of the invention extends axially in two directions, optimizes the connection and torque transmission structure, reduces the rotor mass, shortens the cantilever and support span at two sides, works in a supercritical state, has the rated rotating speed of 80000rpm and the critical rotating speed margin of more than 20 percent, and has the variable working condition of 60 to 100 percent and the self-adaptive balancing capability of axial force.)

1. The flexible rotor of the ultrahigh-speed liquid hydrogen turbopump is characterized by comprising a screw (1), an inducer (2), a compression nut (3), a shaft (4), a primary centrifugal wheel (5), a metal rubber damper (6), a squirrel-cage elastic support (7), a bearing pair (8), an interstage shaft sleeve (9), a secondary centrifugal wheel (10), a balance piston (11), a metal rubber damper baffle (12), a first shaft sleeve (13), a turbine disc (14), a large nut (15), a preloaded disc spring (16) and a second shaft sleeve (17);

one end of the shaft (4) is provided with a screw rod mounting hole, an inducer spline (42), a gland nut screwing thread (43) and a first-stage centrifugal wheel mounting spline (44) are sequentially arranged from the end part, the other end of the shaft (4) is provided with a large nut screwing thread (45), the middle part of the shaft is provided with a second-stage centrifugal wheel mounting spline (46) and a shaft shoulder (47), and a turbine disc matching spline (48) is arranged between the shaft shoulder (47) and the large nut screwing thread (45);

the secondary centrifugal wheel (10) is arranged on the shaft (4) through a secondary centrifugal wheel mounting spline (46) and is positioned on one side of a shaft shoulder (47); a bearing pair (8) is installed on the other side of the shaft shoulder (47), a squirrel-cage elastic support (7) is sleeved on the bearing pair (8), a metal rubber damper (6) is arranged in a zigzag structure of the squirrel-cage elastic support (7), a metal rubber damper baffle plate (12) is positioned between a secondary centrifugal wheel (10) and the metal rubber damper (6), and a balance piston (11) is installed between the secondary centrifugal wheel (10) and the metal rubber damper baffle plate (12); the turbine disc (14) is installed on the shaft (4) through a turbine disc matching spline (48), the first shaft sleeve (13) is installed between the bearing pair (8) and the turbine disc (14), and the turbine disc (14) is pressed and fixed through a large nut (15);

the first-stage centrifugal wheel (5) is arranged on the shaft (4) through a first-stage centrifugal wheel mounting spline (44), and a compression nut (3) and the other bearing pair (8) are respectively arranged on two sides of the first-stage centrifugal wheel (5); an interstage shaft sleeve (9) is arranged between the other bearing pair (8) and the second-stage centrifugal wheel (10), the inducer (2) is arranged on the shaft (4) through an inducer spline (42), and the compression nut (3) is positioned in a hub (21) of the inducer (2) and compresses the first-stage centrifugal wheel (5); the screw (1) is arranged in the screw mounting hole and compresses the inducer (2); a bearing pair (8) at one side of the first-stage centrifugal wheel (5) is provided with a squirrel-cage elastic support (7) and a metal damper (6); a second shaft sleeve (17) and a preloaded disc spring (16) are arranged between the two bearings of the bearing pair (8).

2. The flexible rotor of the ultrahigh-speed liquid hydrogen turbo pump according to claim 1, wherein a front positioning surface (22) is arranged at one end of the inducer (2), the other end of the inducer is hollowed, and a spline a (23) is arranged on the inner wall of the inducer (2).

3. The flexible rotor of the ultra-high rotating speed liquid hydrogen turbopump according to claim 1 or 2, wherein the first-stage centrifugal wheel (5) and the second-stage centrifugal wheel (10) are respectively provided with a front locating surface and a rear locating surface at the installation positions on the shaft (4), wherein the front locating surfaces are respectively internally embedded with an aluminum sleeve (18), and the fit clearance between the aluminum sleeve (18) and the shaft (4) is 0.01 mm-0.02 mm.

4. The ultra-high rotating speed liquid hydrogen turbopump flexible rotor as claimed in claim 3, wherein a shoulder (101) is arranged behind the secondary centrifugal wheel (10), the position of the shoulder (101) is selected by the magnitude of the residual axial force of a shafting, a balance piston cavity (102) is formed among the metal rubber damper baffle (12), the balance piston (11) and the secondary centrifugal wheel (10), and the gap of the balance piston (102) is adjusted to change the pressure in the cavity, so as to change the axial force acting on the secondary centrifugal wheel (10).

5. The ultra-high rotating speed liquid hydrogen turbine pump flexible rotor as claimed in claim 4, characterized in that the bearing in the bearing pair (8) is an angular contact ball bearing, the fit precision of the inner ring and the shaft is within 0.01mm, the preloading disc spring (16) acts on the outer ring, and the compression amount of the preloading disc spring (16) is adjusted through the second shaft sleeve (17).

6. The ultra-high speed liquid hydrogen turbopump flexible rotor as claimed in claim 5, wherein the span of the bearing pair (8) at both ends is one third of the length of the shafting, and the interstage shaft sleeve (9) is made of stainless steel material.

7. The flexible rotor of the ultra-high rotating speed liquid hydrogen turbine pump is characterized in that a positioning surface between the turbine disc (14) and the shaft (4) is in interference fit, the interference is 0.02 mm-0.03 mm, and the turbine disc fitting spline (48) is located below the first shaft sleeve (13).

8. The flexible rotor of the ultra-high rotating speed liquid hydrogen turbo pump according to claim 7, wherein the screw (1), the inducer (2) and the gland nut (3) are made of titanium alloy materials.

9. The ultra-high rotating speed liquid hydrogen turbopump flexible rotor as claimed in claim 8, wherein the first-stage centrifugal wheel (5) and the second-stage centrifugal wheel (10) are made of titanium alloy materials.

10. The ultra-high speed liquid hydrogen turbopump flexible rotor of claim 9, characterized in that the turbine disk (14) is made of titanium alloy material.

Technical Field

The invention relates to a flexible rotor of a turbine pump.

Background

The turbo pump is the heart of an engine, and the improvement of the thrust, the room pressure and the specific impulse of the engine means the great improvement of the lift, the efficiency and the weight power density of the turbo pump. Because the liquid hydrogen has low density and large volume flow, the rotating speed required for reaching the same lift is higher. Therefore, the flexible rotor of the hydrogen turbopump with ultrahigh rotating speed and deep variable working conditions is designed to become one of the key technologies of the expansion cycle engine of the new generation of heavy-duty carrier rockets.

At present, the hydrogen turbo pump speeds of the advanced foreign-level expansion cycle engines VINCI (europe), RL60 (japan) and RD-0146 (russia) all reach 75000rpm and above. The maximum rotating speed of a hydrogen turbine pump of the domestic expansion cycle engine is 60000rpm, and due to reasons of critical rotating speed margin, axial force adaptability and the like, the hydrogen turbine pump cannot work under variable working conditions in a large range, so that the lift, flow and efficiency of the hydrogen turbine pump cannot meet the requirements of the thrust and specific impulse of a new generation of engine.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: in order to meet the requirements of a hydrogen turbopump of a heavy carrier rocket expansion cycle engine of a new generation on high lift, high efficiency and large-range variable working conditions, the flexible rotor of the liquid hydrogen turbopump with the ultrahigh rotating speed is provided, a shaft system extends outwards in two directions, a connection and torque transmission structure is optimized, the mass of the rotor is reduced, cantilevers and support spans on two sides are shortened, supercritical work is realized, the rated rotating speed reaches 80000rpm, the critical rotating speed margin is more than 20%, and meanwhile, the flexible rotor has 60% -100% variable working conditions and axial force self-adaptive balancing capacity.

The technical scheme adopted by the invention is as follows: a flexible rotor of an ultrahigh-rotating-speed liquid hydrogen turbine pump comprises a screw, an inducer, a compression nut, a shaft, a primary centrifugal wheel, a metal rubber damper, a squirrel-cage elastic support, a bearing pair, an interstage shaft sleeve, a secondary centrifugal wheel, a balance piston, a metal rubber damper baffle, a first shaft sleeve, a turbine disc, a large nut, a preloaded disc spring and a second shaft sleeve;

one end of the shaft is provided with a screw rod mounting hole, an inducer spline, a compression nut tightening thread and a first-stage centrifugal wheel mounting spline are sequentially arranged from the end part, the other end of the shaft is provided with a large nut tightening thread, the middle part of the shaft is provided with a second-stage centrifugal wheel mounting spline and a shaft shoulder, and a turbine disc matching spline is arranged between the shaft shoulder and the large nut tightening thread;

the second-stage centrifugal wheel is arranged on the shaft through a second-stage centrifugal wheel mounting spline and is positioned on one side of the shaft shoulder; a bearing pair is arranged on the other side of the shaft shoulder, a squirrel-cage elastic support is sleeved on the bearing pair, a metal rubber damper is arranged in the squirrel-cage elastic support loop structure, a baffle plate of the metal rubber damper is positioned between the secondary centrifugal wheel and the metal rubber damper, and a balance piston is arranged between the secondary centrifugal wheel and the baffle plate of the metal rubber damper; the turbine disc is arranged on the shaft through the turbine disc matched with the spline, the first shaft sleeve is arranged between the bearing pair and the turbine disc, and the turbine disc is tightly pressed and fixed through the large nut;

the first-stage centrifugal wheel is arranged on the shaft through a first-stage centrifugal wheel mounting spline, and a compression nut and another bearing pair are respectively arranged on two sides of the first-stage centrifugal wheel; an interstage shaft sleeve is arranged between the other bearing pair and the second-stage centrifugal wheel, the inducer is arranged on the shaft through an inducer spline, and the compression nut is positioned in a hub of the inducer and compresses the first-stage centrifugal wheel; the screw is arranged in the screw mounting hole and compresses the inducer; a bearing pair on one side of the first-stage centrifugal wheel is provided with a squirrel-cage elastic support and a metal damper; and a second shaft sleeve and a preloaded disc spring are arranged between the two bearings of the bearing pair.

One end in the inducer is provided with a front positioning surface, the other end is hollowed, and the inner wall of the inducer is provided with a spline a.

The first-stage centrifugal wheel and the second-stage centrifugal wheel are respectively provided with a front positioning surface and a rear positioning surface at the installation positions on the shaft, wherein the front positioning surfaces are respectively internally embedded with an aluminum sleeve, and the fit clearance between the aluminum sleeve and the shaft is 0.01 mm-0.02 mm.

A shoulder is arranged behind the secondary centrifugal wheel, the position of the shoulder is selected by the residual axial force of a shaft system, a balance piston cavity is formed among the metal rubber damper baffle, the balance piston and the secondary centrifugal wheel, the pressure in the cavity is changed by adjusting the clearance of the balance piston, and the axial force acting on the secondary centrifugal wheel is further changed.

The bearing centering bearing is an angular contact ball bearing, the matching precision of the inner ring and the shaft is within 0.01mm, the preloading disc spring acts on the outer ring, and the compression amount of the preloading disc spring is adjusted through the second shaft sleeve.

The span of the bearing pair at the two ends is one third of the length of the shaft system, and the interstage shaft sleeve is made of stainless steel materials.

The positioning surface between the turbine disc and the shaft is in interference fit, the interference magnitude is 0.02-0.03 mm, and the turbine disc is matched with the spline and positioned below the first shaft sleeve.

The screw, the inducer and the gland nut are all made of titanium alloy materials.

The first-stage centrifugal wheel and the second-stage centrifugal wheel are made of titanium alloy materials.

The turbine disc is made of titanium alloy material.

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

(1) the flexible rotor can work in a supercritical manner and has variable working condition capability. The maximum rotating speed of a turbopump of the liquid rocket engine is 60000rpm, the working rotating speed reaches 80000rpm, the margin of the second and third-order critical rotating speeds is high, and 60% -100% variable working condition adjustment can be performed.

(2) The axial force of the flexible rotor can be adjusted in an adaptive mode. The angular contact bearings are used in pairs, are integrally designed, realize shafting movement and ensure that the preload force is not changed. A high-sensitivity balance piston is arranged behind the secondary centrifugal wheel, and the pressure in the cavity is changed by adjusting the clearance of the balance piston through the movement of a shaft system, so that the self-adaptive balance of the axial force under the condition of variable working conditions is realized.

(3) The flexible rotor cantilever of the invention is shorter and light. The wheel disc is made of titanium alloy, the inducer is directly connected with the centrifugal wheel, the turbine torque transmission spline is arranged in front, and cantilevers on two sides and concentrated mass are greatly reduced. Meanwhile, the length of a shaft system can be shortened, the weight of a rotor and a corresponding shell is reduced, and the power density ratio of the turbopump is improved.

(4) The flexible rotor of the invention has high operation stability and strong disturbance resistance. By designing the metal rubber damper, larger damping is provided for the rotor, and the supercritical vibration of the rotor can be effectively inhibited.

Drawings

FIG. 1 is an assembly view of a flexible rotor of an ultra-high speed liquid hydrogen turbopump of the invention;

FIG. 2 is a shaft structure view of the invention;

FIG. 3 is a structural view of an inducer of the invention;

FIG. 4 is a view of the structure of a first-stage centrifugal wheel according to the present invention

FIG. 5 is a diagram of a two-stage centrifugal wheel according to the present invention.

Detailed Description

The invention is further illustrated by the following examples.