阅读说明：本技术 一种涡轮泵 (Turbine pump ) 是由 贺博 何尚龙 王少卫 王献 吴泽鹏 于 2021-09-22 设计创作，主要内容包括：本发明属于泵体结构,为解决航天航空动力系统及飞行器流体供应系统中的泵,在提升其转速并改善泵入口汽蚀时,目前采用的方法研制成本高,质量增加过大,结构复杂,系统管路复杂、体积重量较大,在多个转速、较大流量跨度下运行时,适应能力会降低的问题,提供一种涡轮泵,排水壳体内表面位于轴承后侧沿周向开设有多个引流孔,多个引流孔通过排水壳体内开设的引流环槽连通,进水壳体内表面位于诱导轮入口前侧沿周向开设有多个射流孔,多个射流孔通过进水壳体内开设的射流环槽连通,引流环槽与射流环槽之间通过引流管连通,射流孔的轴线相对主轴的延伸方向倾斜设置,进水壳体内表面靠近诱导轮入口处设有扩散段,轴承前侧设有轴承节流板。(The invention belongs to a pump body structure, and aims to solve the problems that the prior method has high development cost, excessive mass increase, complex structure, complex system pipeline, large volume and weight and reduced adaptability when the pump in a fluid supply system of an aerospace power system and an aircraft operates at a plurality of rotating speeds and large flow span when the rotating speed of the pump is increased and the cavitation of a pump inlet is improved, the invention provides a turbine pump, wherein a plurality of drainage holes are circumferentially arranged on the inner surface of a drainage shell positioned at the rear side of a bearing, the drainage holes are communicated through a drainage ring groove arranged in the drainage shell, a plurality of jet holes are circumferentially arranged on the inner surface of a water inlet shell positioned at the front side of an inducer inlet, the jet holes are communicated through a jet ring groove arranged in the water inlet shell, the drainage ring groove is communicated with the jet ring groove through a drainage tube, and the axes of the jet holes are obliquely arranged relative to the extending direction of a main shaft, the inner surface of the water inlet shell is provided with a diffusion section close to the inlet of the inducer, and the front side of the bearing is provided with a bearing throttle plate.)

1. A turbopump comprises a water inlet shell (1), a water discharge shell (5), an inducer (2), an impeller (3) and a main shaft (4);

the water inlet shell (1) and the water drainage shell (5) are connected in a sealing manner to form a shell containing cavity;

main shaft (4) link to each other with drainage casing (5) through bearing (6), inducer (2) and impeller (3) are all overlapped and are established and install on main shaft (4), and are located the casing holds intracavity, its characterized in that:

a plurality of drainage holes (7) are formed in the inner surface of the drainage shell (5) at the rear side of the bearing (6) along the circumferential direction, and the drainage holes (7) are communicated through drainage ring grooves (8) formed in the drainage shell (5);

a plurality of jet holes (9) are formed in the inner surface of the water inlet shell (1) and positioned in front of the inlet of the inducer (2) along the circumferential direction, and the plurality of jet holes (9) are communicated through jet ring grooves (10) formed in the water inlet shell (1);

the drainage ring groove (8) is communicated with the jet flow ring groove (10) through a drainage tube (11);

the axis of the jet hole (9) is obliquely arranged relative to the extending direction of the main shaft (4), and the outlet of the jet hole (9) faces the inlet of the inducer (2);

a diffusion section (12) is arranged on the inner surface of the water inlet shell (1) close to the inlet of the inducer (2), and the inner diameter of the diffusion section (12) is gradually increased along the flowing direction of the fluid;

and a bearing throttle plate (14) is arranged on the front side of the bearing (6).

2. A turbo pump according to claim 1, wherein: the drainage shell (5) is provided with a diversion channel (13);

the inlet of the flow dividing channel (13) is positioned on a fluid flow path between the impeller rear sealing boss (16) and the bearing (6), and the outlet is communicated with the draft tube (11).

3. A turbo pump according to claim 2, wherein: and a spiral supercharging blade (18) is arranged on the outer ring of the rear hub of the impeller (3).

4. A turbo pump according to claim 3, wherein: the bearing throttle plate (14) comprises a throttle plate body (1401);

a plurality of throttle holes (1402) or throttle grooves are uniformly distributed on the throttle plate body (1401) along the circumferential direction.

5. A turbo pump according to any of claims 1 to 4, wherein:

the inner diameter of the jet hole (9) is gradually reduced from an inlet to an outlet;

the inlet diameter A1 of the jet hole (9) is as follows:

wherein Q1 is the drainage flow,the average flow velocity at the inlet of the jet hole (9) is 3-8m/s,the number of jet holes;

the outlet diameter A2 of the jet hole (9) is as follows:

wherein K3 is the jet hole shrinkage.

6. A turbo pump according to claim 5, wherein:

the included angle alpha between the axis of the jet hole (9) and the extension direction of the main shaft (4) is 0-15 degrees;

the contraction angle beta of the jet hole (9) is 0-20 degrees.

7. A turbo pump according to claim 6, wherein: the diameter B of the inlet of the drainage hole (7) is as follows:

wherein the content of the first and second substances,the average flow velocity at the inlet of the drainage hole (7) is 3-8m/s,the number of the drainage holes.

8. A turbo pump according to claim 7, wherein: the distance G between the outlet of the jet hole (9) and the root of the inlet of the blade at the hub position of the inducer (2) is as follows:

wherein K4 is the length coefficient of the jet mixing section, and the value is 3-5.

9. A turbo pump according to claim 8, wherein:

the cross-sectional area SA of the jet flow ring groove (10) is as follows:

wherein the content of the first and second substances,the flow coefficient of the jet ring groove (10) is 0.5-1, and C is the diameter of the drainage tube;

the cross-sectional area SB of drainage annular groove (8) is:

wherein the content of the first and second substances,the flow coefficient of the drainage ring groove (8) is 0.5-1.

10. A turbo pump according to claim 9, wherein: the diameter C of the drainage tube is as follows:

wherein the content of the first and second substances,the average flow velocity in the draft tube 11 is 3-8 m/s.

Technical Field

The invention belongs to a pump body structure, and particularly relates to a turbine pump.

Background

With the development of aerospace technology and the commercialization of the market, various rockets and aircrafts are developed in the direction of high performance, light weight and reusability, and meanwhile, stricter requirements are provided for aerospace power systems and aircraft fluid supply systems, and the fluid supply systems are required to have higher efficiency, lighter weight, smaller volume and stronger adaptability to large working condition changes.

In aerospace power systems and aircraft fluid supply systems, a pump supplies a medium to the system, a large amount of power is consumed, and the volume and the weight of the system are relatively large, so that the most effective method for designing the aerospace power systems and the aircraft fluid supply systems in a miniaturization and lightweight mode is to increase the rotating speed, but the increase of the rotating speed enables cavitation at the inlet of the pump to easily occur, and the system is unstable in operation. The method for improving cavitation mainly comprises the following steps: optimally designing an inducer and an impeller, increasing inlet pressure, adding an auxiliary booster pump or a jet pump at an inlet and the like. Of these, increasing the inlet pressure is the most effective method, the simplest system, but the system reservoir pressure will rise, and when the reservoir volume is large, the mass increase is too large; an auxiliary booster pump is added at the inlet, the rotating speed of the pump is increased most, but the structure is complex, and the auxiliary booster pump can be selected in a large power system; the inducer and the impeller are optimally designed, the volume and the weight of the inducer and the impeller are minimum at the same rotating speed, but the difficulty is high, the rotating speed is limited to be improved particularly at large flow, and the development cost is extremely high; the jet pump is added at the inlet, the rotating speed improving effect is between that of optimally designing the inducer impeller and that of adding the auxiliary booster pump at the inlet, the jet pump needs to be additionally arranged at an inlet pipeline, one path of high-pressure water is led separately, and the whole system is relatively complex and has large volume and weight.

In addition, in an aerospace power system and an aircraft fluid supply system, a high-speed pump used generally operates at a single rotating speed and a single flow point, but with the development of recovery technology, parameters such as thrust of the power system and the like can be required to be changed in a large range, so that the high-speed pump is required to operate at multiple rotating speeds and a large flow span, but due to the fact that a conventional pump is designed according to a rated point, when the conventional pump deviates from a rated working condition, the adaptability of the conventional pump is reduced, for example, when an inducer deviates from the rated working condition, secondary backflow vortex occurs at an inlet.

Disclosure of Invention

The invention provides a turbo pump for solving the technical problems that when the rotating speed of a pump in an aerospace power system and an aircraft fluid supply system is increased and the cavitation of the inlet of the pump is improved, the method of optimally designing an inducer and an impeller, increasing the inlet pressure, adding an auxiliary booster pump or a jet pump at the inlet and the like is adopted, or the actual difficulty is high, the development cost is high, or the mass is increased too much, or the structure is complex, or the system pipeline is complex and the volume and weight are large, and the adaptive capacity can be reduced when a conventional pump operates under the conditions of multiple rotating speeds and large flow span due to the design of rated points.

In order to achieve the purpose, the invention provides the following technical scheme:

a turbo pump comprises a water inlet shell, a water discharge shell, an inducer, an impeller and a main shaft;

the water inlet shell and the water discharge shell are hermetically connected to form a shell cavity;

the main shaft is connected with the drainage shell through a bearing, the inducer and the impeller are sleeved on the main shaft and positioned in the shell containing cavity, and the device is characterized in that,

a plurality of drainage holes are formed in the inner surface of the drainage shell, which is positioned on the rear side of the bearing along the circumferential direction, and are communicated through drainage ring grooves formed in the drainage shell;

a plurality of jet holes are formed in the inner surface of the water inlet shell on the front side of the inducer inlet along the circumferential direction and are communicated through jet ring grooves formed in the water inlet shell;

the drainage ring groove is communicated with the jet ring groove through a drainage tube;

the axis of the jet hole is obliquely arranged relative to the extending direction of the main shaft, and the outlet of the jet hole faces the inlet of the inducer wheel;

the inner surface of the water inlet shell is provided with a diffusion section close to the inlet of the inducer, and the inner diameter of the diffusion section is gradually increased along the flowing direction of the fluid;

and a bearing throttle plate is arranged on the front side of the bearing.

Furthermore, the drainage shell is provided with a diversion channel;

the inlet of the flow dividing channel is positioned on a path through which fluid flows between the impeller rear sealing boss and the bearing, and the outlet of the flow dividing channel is communicated with the drainage tube.

Furthermore, the outer ring of the rear hub of the impeller is provided with spiral supercharging blades.

Further, the bearing throttle plate includes a throttle plate body;

and a plurality of throttling holes or throttling grooves are uniformly distributed on the throttling plate body along the circumferential direction.

Further, the inner diameter of the jet hole is gradually reduced from the inlet to the outlet;

the jet hole inlet diameter A1 is:

wherein Q1 is the drainage flow, V_AThe average flow velocity at the inlet of the jet hole is 3-8m/s, N_AThe number of jet holes;

the jet hole outlet diameter A2 is as follows:

A2＝K3*A1

wherein K3 is the jet hole shrinkage.

Furthermore, the included angle alpha between the axis of the jet hole and the extension direction of the main shaft is 0-15 degrees;

the contraction angle beta of the jet hole is 0-20 degrees.

Further, the diameter B of the inlet of the drainage hole is as follows:

wherein, V_BThe average flow velocity at the inlet of the drainage hole is 3-8m/s, N_BThe number of the drainage holes.

Further, the distance G between the outlet of the jet hole and the root of the inlet of the blade at the hub position of the inducer is as follows:

G＝K4*(N_A*A2²)^0.5

wherein K4 is the length coefficient of the jet mixing section, and the value is 3-5.

Further, the cross-sectional area SA of the jet flow ring groove is as follows:

SA＝K5*0.25*π*C²

wherein K5 is the flow coefficient of the jet ring groove, the value is 0.5-1, and C is the diameter of the drainage tube;

the cross-sectional area SB of the drainage ring groove is as follows:

SB＝K6*0.25*π*C²

wherein K6 is a flow coefficient of the drainage ring groove, and the value is 0.5-1.

Further, the draft tube diameter C is:

wherein, V_CThe average flow velocity in the drainage tube is 3-8 m/s.

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

1. according to the turbine pump, the shell of the turbine pump is optimized and improved, the pressure at the inlet of the impeller blade of the pump can be increased, the flowing state of the inlet of the pump is improved, the jet hole is formed in the inlet of the water inlet shell, the secondary backflow vortex at the top of the inlet of the impeller can be inhibited, the cavitation resistance is improved, the rotating speed of the pump is further increased, the size and the weight of the pump are effectively reduced, meanwhile, the pump can stably run in a large flow range and a large rotating speed range, and the flow of fluid can be smoothly transited due to the arrangement of the diffusion section. In addition, when the requirement for cavitation allowance is high, the inlet pressure of the inducer is required to be high, the flow rate of the inducer is large, the flow passing through the bearing is large, the flow speed is high, the bearing is cooled sufficiently, but the rolling body and the retainer of the bearing need to bear larger fluid load force and larger impact force, the running state is poorer, the stability and the service life of the bearing can be influenced and reduced, the flow passing through the bearing can be controlled by increasing the throttle plate of the bearing, and the running state of the bearing is improved.

2. The invention is also provided with a shunt channel which can ensure sufficient drainage and jet flow.

3. The inner diameter of the jet hole is gradually reduced from the inlet to the outlet, so that the pressure of fluid flowing out of the jet hole can be further improved.

4. According to the invention, through the design of the structure and parameters of the turbine pump, the cavitation resistance of the pump can be effectively improved, the inlet pressure of the pump is reduced (from the system perspective, the pressure at the inlet flange of the pump can be reduced under the same cavitation requirement), the pressure and the weight of the storage tank are further reduced, and the inlet pressure can be reduced by 0.05-0.15 MP. In addition, the invention can improve the rotating speed of the pump and reduce the weight and the size of the pump under the condition of not changing system parameters. According to the flow, the lift and the structural difference of the pump, the rotating speed can be improved by 20 to 50 percent, and the weight can be reduced by about 5 to 20 percent.

Drawings

FIG. 1 is a schematic structural diagram according to a first embodiment of the present invention;

FIG. 2 is a schematic structural diagram according to a second embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a third embodiment of the present invention;

FIG. 4 is an enlarged view of a portion of the present invention at N in FIGS. 1-3;

FIG. 5 is an enlarged view of a portion of the present invention at M in FIGS. 1-3;

FIG. 6 is an enlarged view of a portion of the invention at Y in FIG. 1;

FIG. 7 is a schematic view of a bearing throttle plate according to an embodiment of the present invention;

the device comprises a water inlet shell, 2-inducer, 3-impeller, 4-main shaft, 5-drainage shell, 6-bearing, 7-drainage hole, 8-drainage ring groove, 9-jet hole, 10-jet ring groove, 11-drainage tube, 12-diffusion section, 13-shunt channel, 14-bearing throttle plate, 1401-throttle plate body, 1402-throttle hole, 15-impeller front sealing boss, 16-impeller rear sealing boss, 17-nut and 18-spiral pressurizing blade, wherein the impeller comprises a main shaft, a main shaft and a main shaft.

Detailed Description

The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention and the accompanying drawings, and it is obvious that the described embodiments do not limit the present invention.

Example one

As shown in fig. 1 and 4 to 6, a turbo pump includes a water inlet casing 1, a water discharge casing 5, an inducer 2, an impeller 3 and a main shaft 4, wherein the water inlet casing 1 and the water discharge casing 5 are hermetically connected to form a casing accommodating cavity, the main shaft 4 is connected to the water discharge casing 5 through a bearing 6, the inducer 2 and the impeller 3 are both sleeved on the main shaft 4 and are located in the casing accommodating cavity, a nut 17 is installed at the front end of the main shaft 4 for fixing the inducer 2 and the impeller 3 on the main shaft 4, and the main structure of the turbo pump is similar to that of an existing turbo pump, so that other specific structures of the turbo pump are not described in detail. In order to control the flow rate passing through the bearing 6 and improve the running state of the bearing 6, a bearing throttle plate 14 is arranged on the front side of the bearing 6, as shown in fig. 7, the bearing throttle plate 14 comprises a throttle plate body 1401, a plurality of throttle holes 1402 are uniformly distributed on the throttle plate body 1401 along the circumferential direction, and the throttle holes 1402 are kidney-shaped holes. The spiral supercharging blade 18 is arranged on the outer ring of the hub behind the impeller 3 at the front side of the bearing throttle plate 14, so that fluid can smoothly pass through the bearing, and the number of blades, the pitch and the like of the spiral supercharging blade 18 can be adjusted and designed according to the flowing condition of the fluid. A plurality of drainage holes 7 have been seted up along circumference to 5 internal surfaces of drainage casing located the 6 rear sides of bearing, and a plurality of drainage holes 7 communicate through the drainage annular 8 that sets up in drainage casing 5, and the quantity of drainage hole 7 is generally 3 at least, can adjust as required by design. In addition, the drainage shell 5 is also provided with a diversion channel 13, the inlet of the diversion channel 13 is positioned on the path of fluid flowing between the impeller rear sealing boss 16 and the bearing 6, the outlet is communicated with the drainage ring groove 8, the diversion channel 13 can be an opened hole or a set corresponding groove, the form is not limited, and the diversion channel 13 is arranged so that the flow of drainage and jet flow is sufficient. A plurality of jet holes 9 have been seted up along the circumference to 1 internal surface of casing of intaking lie in inducer 2 entry front side, and a plurality of jet holes 9 are through the jet ring groove 10 intercommunication of seting up in the casing of intaking 1, and the quantity of jet hole 9 is also generally 3 at least, also can adjust according to the design needs, and the internal diameter of jet hole 9 reduces gradually by the entry to the export also can be straight-through. The drainage ring groove 8 is communicated with the jet ring groove 10 through a drainage tube 11, the drainage tube 11 can be a pipeline arranged outside the water inlet shell 1 and the water outlet shell 5, the axis of the jet hole 9 is obliquely arranged relative to the extending direction of the main shaft 4, and the outlet of the jet hole 9 faces the inlet of the inducer 2, so that fluid flowing out of the jet hole 9 is ejected towards the inner side. The inner surface of the water inlet shell 1 is also provided with a section of diffusion section 12 close to the inlet of the inducer 2, and the inner diameter of the diffusion section 12 is gradually increased along the flowing direction of the fluid.

In the first embodiment of the present invention, only one form of the orifice 1402 is shown, and the orifice 1402 may be other forms, such as a circular hole or other special-shaped holes, or may be provided with a throttling groove, as long as the total flow area can be ensured.

When the structure of the first embodiment works, a main stream of medium fluid enters from the left side of the water inlet shell 1, is pressurized by the inducer 2 and the impeller 3 in sequence and then is discharged from the water discharge shell 5, a secondary stream of medium fluid is divided into two paths, one path of medium fluid flows from the front cavity of the impeller 3 to the inlet of the impeller 3 through the front sealing boss 15 of the impeller and then enters the impeller 3 under the action of the main stream, when the design working condition is deviated, a tip medium of the inducer 2 flows back from a tip clearance to the inlet of the inducer 2 to form a vortex at the inlet, the other path of medium fluid flows from the rear cavity of the impeller 3 to the rear sealing boss 16 of the impeller, flows through the bearing throttle plate 14 and then flows through a clearance of the bearing 6, enters the drainage ring groove 8 from the drainage hole 7, passes through the drainage tube 11 and enters the drainage ring groove 10, is discharged from the jet hole 9, can inhibit the secondary reflux of the tip of the inducer 2, is converged with a low-pressure main stream, the pressure near the inlet of the inducer 2 is increased, the inlet pressure of the inducer 2 can be effectively increased. The diffuser section 12 is provided to enable smooth transition of fluid flow.

In addition, in practical application, the turbo pump structure in the first embodiment can be implemented in two ways, and the first is to improve the existing turbo pump structure, and reduce the inlet pressure to reduce the system weight without changing the inducer 2 and the impeller 3; secondly, according to new system requirements, the design processing capacity of the existing inducer 2 and the impeller 3 is combined, and the parameters of the pump are determined. A design method of the second embodiment is as follows:

(1) firstly, determining inlet pressure P1 of an inducer 2 (the inlet of the inducer 2 refers to a section corresponding to the intersection point of an impeller inlet of the inducer 2 and a hub) according to system parameters and the pump rotating speed;

(2) according to pump outlet flow Q, pump outlet pressure P, pump speed n and impeller 3 structure parameters, through empirical calculation or simulation calculation, determining impeller rear seal boss 16 front pressure P2:

p2 ═ P (0.7-0.95), where P is pump outlet pressure;

(3) determining the outlet pressure P5 of the jet hole 9

K1 (Q × P0+ Q1 × P5) ═ Q + Q1 × P1, where K1 is the flow mixing coefficient, and K1 is 0.1 to 0.5 (based on simulation and experimental confirmation), typically 0.3;

q1 is the drainage flow, P0 is the pump inlet pressure;

q1 is K2Q, K2 is the drainage flow rate, K2 is 0.1-0.35, generally 0.2;

(4) determining the back pressure P3 of the impeller back seal boss 16

D is the diameter of the impeller rear sealing boss 16, F is the clearance of the impeller rear sealing boss 16, generally (0.001-0.005) × D, E is the effective length of the impeller rear sealing boss 16, rho is the fluid density, u is the dynamic viscosity, and v is the kinematic viscosity;

(5) as shown in fig. 3 and 4, according to the drainage flow Q1, other relevant parameters are calculated:

jet hole 9 inlet diameter a 1:

V_Athe average flow velocity at the inlet of the jet hole 9 is 3-8m/s, N_AThe number of jet holes;

the outlet diameter A2 of the jet hole 9 is as follows:

A2＝K3*A1

wherein K3 is the shrinkage rate of the jet hole, and generally takes a value of 0.4-1, and the smaller the difference between P1 and P0 is, the larger the value of K3 is;

an included angle alpha between the axis of the jet hole 9 and the extension direction of the main shaft 4 (namely, the included angle between the jet hole 9 and the main flow) is 0-15 degrees, the contraction angle beta of the jet hole 9 is 0-20 degrees, and the diffusion angle gamma of the front diffusion section 12 at the inlet of the inducer 2 is 5-15 degrees;

the diameter B of the inlet of the drainage hole 7 is as follows:

wherein, V_BThe average flow velocity at the inlet of the drainage hole 7 is 3-8m/s, N_BThe number of drainage holes;

the diameter C of the draft tube 11 is:

wherein, V_CThe average flow velocity in the drainage tube 11 is 3-8 m/s;

the distance G between the outlet of the jet hole 9 and the root of the hub inlet of the inducer 2 is as follows:

G＝K4*(N_A*A2²)^0.5

wherein K4 is the length coefficient of the jet flow mixing section, and the value is 3-5;

the cross-sectional area SA of the jet ring groove 10 is:

SA＝K5*0.25*π*C²

wherein K5 is the flow coefficient of the jet ring groove 10, the value is 0.5-1, and C is the diameter of the drainage tube;

the cross-sectional area SB of the drainage ring groove 8 is:

SB＝K6*0.25*π*C²

wherein K6 is the flow coefficient of the drainage ring groove 8, and the value is 0.5-1.

(6) According to the bearing overflowing flow q of the bearing 6, the inner diameter of the bearing throttle plate 14 is equal to the inner diameter of the bearing 6, and the outer diameter d3 is as follows:

d3＝Z2-3R；

wherein Z2 is the outer diameter of the bearing 6, and R is the fillet of the outer ring of the bearing 6;

the number of orifices 1402 on the bearing throttle plate 14 is generally not less than 3, and can be the same as the number of rolling elements;

orifice 1402 has an aperture d0 (diameter of the semicircle at both ends of the waist-shaped hole in the first embodiment) as follows:

V_dthe value is 3-8 m/s;

orifice 1402 pitch diameter d2

d2＝0.5*(Z3+Z4)

Wherein Z3 is the outer diameter of the inner ring of the bearing 6, and Z4 is the inner diameter of the outer ring of the bearing 6.

According to the calculation structure, the structure design is completed, Q1, P1, P2, P3, P4 (pressure in the drainage ring groove 8) and P5 are evaluated through simulation calculation, iterative design is carried out according to a simulation result, meanwhile, verification is carried out by combining experiments, the P1 meets the design requirement by adjusting the structure, other parameters meet the system requirement, and meanwhile, the wall thickness of the drainage tube 11 can be designed according to the P4.

After the design according to the above method, it is verified that in the first embodiment of the present invention, under the condition that the cavitation requirement of the system is not changed, the pressure at the inlet of the pump (flange) can be reduced by 0.05-0.15MPa, and under the condition that the pressure of the system is not changed (i.e., the pressure at the inlet of the pump is not changed, and the cavitation requirement of the pump is not changed), the rotation speed can be increased by 20-50%, and the weight can be reduced by about 5-20%. Particularly, when the requirement for the cavitation margin is high, the pressure of P1 is required to be high, the flow rate of Q1 is required to be large, the flow passing through the bearing 6 is too large, the flow speed is too high, the cooling of the bearing 6 is sufficient, but a rolling body and a retainer of the bearing need to bear large fluid load force and large impact force, the running state is poor, the stability and the service life of the bearing 6 are low, the flow passing through the bearing 6 can be controlled by increasing the throttle plate 14 of the bearing, and the running state of the bearing 6 is improved.

Example two

As shown in fig. 2, the second embodiment of the present invention is different from the first embodiment in that the spiral supercharging blade 18 is not provided, and the flow process of the fluid is not affected.

EXAMPLE III

As shown in fig. 3, the difference between the third embodiment of the present invention and the second embodiment of the present invention is that the flow dividing channel 13 is not provided, and the fluid flowing through the impeller rear sealing boss 16 does not directly enter the draft tube 11, passes through the bearing throttle plate 14 and the bearing 6 in sequence, enters the draft ring groove 8 through the draft hole 7, and then passes through the draft tube 11 to the jet ring groove 10.

It should also be noted that the solution of the invention can be directly applied to other high-speed pumps.

In the traditional production and manufacturing process, the forming process is limited, the machining of the turbine pump shell has certain difficulty, and if the forming process is complex, the turbine pump shell can be machined in a 3D printing mode, such as 3D printing metal forming, 3D printing sand mold forming, investment casting forming, welding machining forming and the like.

V of the foregoing_AAnd V_CThe flow rate is selected mainly by considering the structural size of the water inlet shell 1, the structural size of the water discharge shell 5, the structure of the drainage tube 11 and the installation size, and the flow resistance of the whole drainage, jet flow and return circuit is considered at the same time, and the flow resistance of the whole return circuit is generally controlled within 1.5 MPa. V_BOn the basis of considering the structure, the mainstream flow velocity is also considered, and generally V is mainly considered_BThe flow velocity of the main flow is 1.1-1.5 times of the flow velocity of the main flow, so that mixed flow disturbance is reduced.

The above description is only an embodiment of the present invention, and is not intended to limit the scope of the present invention, and all equivalent structural changes made by using the contents of the present specification and the drawings, or applied directly or indirectly to other related technical fields, are included in the scope of the present invention.