CN111536077A - High-specific-speed double-outlet volute centrifugal pump - Google Patents

Abstract

The invention discloses a high specific speed double outlet volute centrifugal pump. An impeller is arranged at the inner annular opening of the double outlet volute, a suction pipe is connected at the bottom of the impeller, and two water outlets of the double outlet volute are A water outlet pipe is connected; the blade of the impeller adopts a quasi-cylindrical twisted structure, and the front and back sides of the blade are smoothly connected by curved surfaces with different curvatures from top to bottom; on the axis. The invention realizes two-way water outlet through two water outlets, improves the outflow efficiency of the centrifugal pump, and at the same time enhances the velocity component of the water flow in the circumferential direction of the volute, improves the water flow conditions at the outlet of the volute, reduces hydraulic loss, and makes centrifugal The pump has good hydraulic performance and operating efficiency.

Description

A high specific speed double outlet volute centrifugal pump

technical field

The invention relates to a high specific rotational speed double outlet volute centrifugal pump, belonging to the technical field of centrifugal pumps.

Background technique

The main flow components of the centrifugal pump are the impeller and the pressurized water chamber. The pressurized water chamber is also known as the volute because of its gradual diffusion shape. The volute is the necessary place for the centrifugal pump to discharge the fluid and pressurize the fluid, so its hydraulic structure has a crucial influence on the efficiency of the centrifugal pump.

At present, people's research on the centrifugal pump volute mainly focuses on the area and shape of the section, the throat area and the angle of the separation tongue. The number of outlets of the volute has not been changed, and the design and optimization have been made to improve the pump efficiency.

Therefore, how to overcome the deficiencies of the prior art has become one of the key problems to be solved urgently in the technical field of centrifugal pumps.

SUMMARY OF THE INVENTION

Objective: In order to overcome the deficiencies in the prior art, the present invention provides a high specific speed double outlet volute centrifugal pump.

Technical scheme: in order to solve the above-mentioned technical problems, the technical scheme adopted in the present invention is:

A high specific speed double outlet volute centrifugal pump, comprising a double outlet volute, an impeller is arranged at the inner annular opening of the double outlet volute, a suction pipe is connected at the bottom of the impeller, and two double outlet volutes are provided. The water outlets are all connected with water outlet pipes; the blades of the impeller adopt a quasi-cylindrical twisted structure, and the front and back sides of the blades are smoothly connected by curved surfaces with different curvatures from top to bottom; The center is on the same axis; the cross-sectional airfoil curves of the front and back surfaces of the blade from top to bottom are set as follows:

At 50mm from the top of the impeller, the cross-sectional airfoil curve formula of the curved surface of the blade front is as follows:

y=-0.72425x ² +17.24068x+23.91072

The cross-sectional airfoil curve formula of the curved surface on the opposite side of the blade is as follows:

y=0.00683x ³ -0.95369x ² +18.94882x+19.35635

At 150mm from the top of the impeller, the cross-sectional airfoil curve formula of the curved surface on the front of the blade is as follows:

y = -1.33765×10 ^-7 x ⁴ +4.63929×10 ^-5 x ³ -0.00788x ² +0.55646x+112.20597

The cross-sectional airfoil curve formula of the curved surface on the opposite side of the blade is as follows:

y = -1.36421×10 ^-7 x ⁴ +4.8806×10 ^-5 x ³ -0.00847x ² +0.60056x+106.91616

At 250mm from the top of the impeller, the cross-sectional airfoil curve formula of the curved surface of the blade front is as follows:

y = -1.3079×10 ^-7 x ⁴ +4.53574×10 ^-5 x ³ -0.00779x ² +0.5519x+112.99371

The cross-sectional airfoil curve formula of the curved surface on the opposite side of the blade is as follows:

y = -1.3285×10 ^-7 x ⁴ +4.75536×10 ^-5 x ³ -0.00835x ² +0.59518x+107.68838

At a distance of 350mm from the top of the impeller, the cross-sectional airfoil curve formula of the curved surface of the blade front is as follows:

y=-2.00056×10 ^-6 x ⁴ +5.66272×10 ^-5 x ³ -0.003x ² +0.51281x+107.29902

The cross-sectional airfoil curve formula of the curved surface on the opposite side of the blade is as follows:

y = -2.78571×10 ^-6 x ⁴ -1.36515×10 ^-5 x ³ -0.00192x ² +0.54119x+112.37151

At a distance of 450mm from the top of the impeller, the cross-sectional airfoil curve formula of the curved surface of the blade front is as follows:

y=0.14938x ³ +26.43681x ² +1561.70207x+30844.31736

The cross-sectional airfoil curve formula of the curved surface on the opposite side of the blade is as follows:

y= ^0.00199x3 +0.23735x2 ⁺ 10.55235x+244.36147.

As a preferred solution, the water inlet edge of the blade extends to the inlet of the bottom of the impeller.

As a preferred solution, there are two water outlets in the circumferential direction of the double outlet volute, and the two water outlets are axially symmetrical.

As a preferred solution, the impeller is formed at one time by a casting process.

As a preferred solution, the number of the blades is 5-8.

As a preferred solution, the number of the blades is 6.

As a preferred solution, the water outlet section of the double outlet volute is a circular section.

Beneficial effects: the present invention provides a high specific speed double outlet volute centrifugal pump, the centrifugal pump uses the double outlet volute, and realizes two-way water outlet through two water outlets, which improves the outflow efficiency of the centrifugal pump and enhances the water flow at the same time. The velocity component in the circumferential direction of the volute improves the water flow conditions at the outlet of the volute, reduces hydraulic loss, and enables the centrifugal pump to have good hydraulic performance and operating efficiency.

Description of drawings

FIG. 1 is a schematic structural diagram of a high specific speed double outlet volute centrifugal pump proposed by the present invention.

Figure 2 is a front triaxial view of a single blade proposed by the present invention.

Figure 3 is a top view of a single blade proposed by the present invention.

FIG. 4 is a schematic diagram of the airfoil curves at different axial distances from the top of the impeller on the blade proposed by the present invention.

Figure 5 is a front view of the impeller proposed by the present invention.

FIG. 6 is a schematic diagram of the composition structure of a plurality of blades in the impeller proposed by the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1, a high specific rotational speed double outlet volute centrifugal pump includes a suction pipe 1, an impeller 2, a double outlet volute 3 and a water outlet pipe 4 in sequence according to the direction of water flow. The double outlet volute 3 The inner annular opening is provided with an impeller 2 , the bottom of the impeller 2 is connected with a water suction pipe 1 , and the two water outlets of the double outlet volute 3 are connected with a water outlet pipe 4 .

As shown in Figures 2-4, the blades of the impeller 2 adopt a quasi-cylindrical twisted structure, the front and back surfaces of the blades 201 are smoothly connected from top to bottom by curved surfaces with different curvatures, and the front and back surfaces of the blades 201 are curved from top to bottom. The section airfoil curve is set as follows:

50mm from the top of the impeller 2, the values of the point coordinates on the airfoil curves of the front and back sections of the blade 201 are shown in Table 1.

Table 1

The two fitted curves are expressed as:

Front of the leaf:

y=-0.72425x ² +17.24068x+23.91072

The reverse side of the blade:

y=0.00683x ³ -0.95369x ² +18.94882x+19.35635

150mm from the top of the impeller 2, the values of the point coordinates on the airfoil curves of the front and back sections of the blade 201 are shown in Table 2.

Table 2

The two fitted curves are expressed as:

Front of the leaf:

y = -1.33765×10 ^-7 x ⁴ +4.63929×10 ^-5 x ³ -0.00788x ² +0.55646x+112.20597

The reverse side of the blade:

y = -1.36421×10 ^-7 x ⁴ +4.8806×10 ^-5 x ³ -0.00847x ² +0.60056x+106.91616

250mm from the top of the impeller 2, the values of the point coordinates on the airfoil curves of the front and back sections of the blade 201 are shown in Table 3.

table 3

The two fitted curves can be expressed as:

Front of the leaf:

y = -1.3079×10 ^-7 x ⁴ +4.53574×10 ^-5 x ³ -0.00779x ² +0.5519x+112.99371

Back of the blade:

y = -1.3285×10 ^-7 x ⁴ +4.75536×10 ^-5 x ³ -0.00835x ² +0.59518x+107.68838

350mm from the top of the impeller 2, the values of the point coordinates on the airfoil curves of the front and back sections of the blade 201 are shown in Table 4.

Table 4

The two fitted curves are expressed as:

Front of the leaf:

y=-2.00056×10 ^-6 x ⁴ +5.66272×10 ^-5 x ³ -0.003x ² +0.51281x+107.29902

Back of the blade:

y = -2.78571×10 ^-6 x ⁴ -1.36515×10 ^-5 x ³ -0.00192x ² +0.54119x+112.37151

450mm from the top of the impeller 2, the values of the point coordinates on the airfoil curves of the front and back sections of the blade 201 are shown in Table 5.

table 5

The two fitted curves are expressed as:

Front of the leaf:

y=0.14938x ³ +26.43681x ² +1561.70207x+30844.31736

Back of the blade:

y= ^0.00199x3 +0.23735x2 ⁺ 10.55235x+244.36147

As shown in Figure 5-6, the number of blades of the impeller 2 is 5-8, and the water inlet edge of the blades extends to the bottom inlet of the impeller 2 to improve the cavitation performance.

The centers of the water suction pipe 1 , the impeller 2 and the double outlet volute 3 are on the same axis.

The double-outlet volute 3 has two water outlets in the circumferential direction, and the two water outlets are arranged axially symmetrically, and the impeller is formed by a casting process at one time.

Example 1:

The optimized design of a centrifugal pump, the rated flow of the pump is 367m3/h, the head is 25m, and the specific speed is 208.

The optimized parameters of the invention are as follows: the diameter of the inlet at the bottom of the impeller is 1700 mm, the diameter of the outlet at the top of the impeller is 4100 mm, and the outer diameter of the double outlet volute is 4160 mm. The water outlet section of the double outlet volute is a circular section with a diameter of 1700mm, which is directly connected to the water outlet pipe. The number of impeller blades is 6, and the blades adopt a quasi-cylindrical and equal-thickness twisted structure.

Example 2:

The optimized parameters of the invention are as follows: the diameter of the inlet at the bottom of the impeller is 1700 mm, the diameter of the outlet at the top of the impeller is 4100 mm, and the outer diameter of the double outlet volute is 4160 mm. The water outlet section of the double outlet volute is a circular section with a diameter of 1700mm, which is directly connected to the water outlet pipe. The number of impeller blades is 8, and the blades adopt a quasi-cylindrical and equal-thickness twisted structure.

Example 3:

The specific application process of the present invention is as follows: the pump body of the centrifugal pump and the water suction pipe 1 are filled with water first, the motor drives the impeller 2 to rotate, the water between the blades in the impeller starts to rotate, and the water is thrown from the center of the impeller 2 to the outer edge of the impeller. High pressure is discharged from two water outlets. At the same time, due to the pressure difference, the impeller 2 keeps rotating, and the liquid also continuously enters from the suction pipe 1 and flows out from the water outlet pipe 4 through the double outlet volute 3.

The descriptions not involved in the specific embodiments of the present invention belong to the well-known technology in the art, and can be implemented with reference to the well-known technology.

The above is only the preferred embodiment of the present invention, it should be pointed out that: for those skilled in the art, without departing from the principle of the present invention, several improvements and modifications can also be made, and these improvements and modifications are also It should be regarded as the protection scope of the present invention.

Claims (7)

1. a high specific rotating speed double outlet volute centrifugal pump, is characterized in that: comprise double outlet volute, described double outlet volute inner annular opening is provided with impeller, and the bottom of impeller is connected with suction pipe, and the double outlet is provided with an impeller. The two water outlets of the volute are connected with water outlet pipes; the blades of the impeller adopt a quasi-cylindrical twisted structure, and the front and back sides of the blades are smoothly connected from top to bottom by curved surfaces with different curvatures; the water suction pipes, impeller, The center of the double outlet volute is on the same axis; the cross-sectional airfoil curves of the front and back surfaces of the blades from top to bottom are set as follows: At 50mm from the top of the impeller, the cross-sectional airfoil curve formula of the curved surface of the blade front is as follows: y=-0.72425x ² +17.24068x+23.91072 The cross-sectional airfoil curve formula of the curved surface on the opposite side of the blade is as follows: y=0.00683x ³ -0.95369x ² +18.94882x+19.35635 At 150mm from the top of the impeller, the cross-sectional airfoil curve formula of the curved surface on the front of the blade is as follows: y = -1.33765×10 ^-7 x ⁴ +4.63929×10 ^-5 x ³ -0.00788x ² +0.55646x+112.20597 The cross-sectional airfoil curve formula of the curved surface on the opposite side of the blade is as follows: y = -1.36421×10 ^-7 x ⁴ +4.8806×10 ^-5 x ³ -0.00847x ² +0.60056x+106.91616 At 250mm from the top of the impeller, the cross-sectional airfoil curve formula of the curved surface of the blade front is as follows: y = -1.3079×10 ^-7 x ⁴ +4.53574×10 ^-5 x ³ -0.00779x ² +0.5519x+112.99371 The cross-sectional airfoil curve formula of the curved surface on the opposite side of the blade is as follows: y = -1.3285×10 ^-7 x ⁴ +4.75536×10 ^-5 x ³ -0.00835x ² +0.59518x+107.68838 At a distance of 350mm from the top of the impeller, the cross-sectional airfoil curve formula of the curved surface of the blade front is as follows: y=-2.00056×10 ^-6 x ⁴ +5.66272×10 ^-5 x ³ -0.003x ² +0.51281x+107.29902 The cross-sectional airfoil curve formula of the curved surface on the opposite side of the blade is as follows: y = -2.78571×10 ^-6 x ⁴ -1.36515×10 ^-5 x ³ -0.00192x ² +0.54119x+112.37151 At a distance of 450mm from the top of the impeller, the cross-sectional airfoil curve formula of the curved surface of the blade front is as follows: y=0.14938x ³ +26.43681x ² +1561.70207x+30844.31736 The cross-sectional airfoil curve formula of the curved surface on the opposite side of the blade is as follows: y= ^0.00199x3 +0.23735x2 ⁺ 10.55235x+244.36147. 2 . The high specific rotational speed double outlet volute centrifugal pump according to claim 1 , wherein the water inlet edge of the blade extends to the inlet of the bottom of the impeller. 3 . 3 . The high specific rotational speed double outlet volute centrifugal pump according to claim 1 , wherein: the double outlet volute has two water outlets in the circumferential direction, and the two water outlets are axially symmetrical. 4 . 4 . The high specific rotational speed double outlet volute casing centrifugal pump according to claim 1 , wherein the impeller is formed at one time by a casting process. 5 . 5 . The high specific speed double outlet volute centrifugal pump according to claim 1 , wherein the number of the blades is 5-8. 6 . 6 . The high specific rotational speed double outlet volute centrifugal pump according to claim 5 , wherein the number of the blades is 6. 7 . 7 . The high specific rotational speed double outlet volute centrifugal pump according to claim 1 , wherein the cross section of the water outlet of the double outlet volute is a circular section. 8 .

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