KR101178922B1 - Impeller for pump - Google Patents

Abstract

(상기 수학식의 r_i는 상기 흡입면 날개부의 시작점의 반경을 나타낸 것이고, 비틀림 각(β)은 상기 흡입면 날개부의 곡률반경(r) 방향에 대해 직교되는 선(a)과, 상기 흡입면 날개부의 접선(b) 사이의 각을 나타낸 것이며, ln은 자연로그(log_e)이다.)
이에 의해, 브레이드의 입사면 비틀림 각(β)을 26 ~ 34°범위에서 선택된 각도로 전 영역에 걸쳐 형성하고 블레이드의 전체 형성각도(α)를 325 내지 370°로 형성함으로써 펌프 효율이 60%에 근접하거나 이상인 펌프를 구현할 수 있으므로, 50% 정도인 종래 원심펌프 효율에 비해 획기적으로 펌프 효율을 향상시킬 수 있다. 그리고, 2 개의 블레이드를 갖는 구조로 형성함으로써 슬러리의 이송시에 막힘 현상이 최소화할 수 있고 낮은 비속도에서도 효율적인 운전이 가능한 효과가 있다. The present invention relates to a pump impeller, and more particularly, to a pump impeller that can minimize the blockage during the transport of the slurry, and can be operated efficiently even at a low specific speed.
The pump impeller of the present invention has a blade comprising a suction surface wing formed in the suction region of the object to be sucked from the center of the hub, and a discharge surface wing portion extending in the end of the suction surface wing and formed in the discharge region of the object to be sucked. In one pump impeller, the placement angle θ (r) of the suction surface vane is formed to satisfy the following equation, and the torsion angle β of the suction surface vane is an angle specified in the range of 26 to 34 °. It is characterized in that it is formed to have the same value in the entire area.

(R _i in the above equation represents the radius of the starting point of the suction surface blade, the torsion angle β is a line (a) orthogonal to the curvature radius (r) direction of the suction surface blade, and the suction surface The angle between the tangent (b) of the wing, ln is the natural log (log _e ).)
Thereby, the incidence plane twist angle β of the braid is formed over the entire area at an angle selected from the range of 26 to 34 ° and the overall formation angle α of the blade is formed to be 325 to 370 ° so that the pump efficiency is 60%. Since it is possible to implement a pump close to or above, it can significantly improve the pump efficiency compared to the conventional centrifugal pump efficiency of about 50%. In addition, by forming a structure having two blades, clogging may be minimized during the transfer of the slurry, and an efficient operation may be performed even at a low specific speed.

Description

Pump impeller {IMPELLER FOR PUMP}

The present invention relates to a pump impeller, and more particularly, to a pump impeller that can minimize the blockage during the transport of the slurry, and can operate efficiently even at a low specific speed.

In general, a pump is a mechanical device for transporting a fluid through a pipe by using a pressure action. When the pump is classified into a structure, there are a reciprocating pump, a rotary pump, a centrifugal pump, an axial flow pump, a friction pump, and the like. And pumps of a suitable type are selected and used according to the flow rate.

In addition, pumps are subdivided into various forms according to the development of the industrial society, and are being developed to meet the purpose of use and characteristics. For example, in places such as water purification plants, wastewater treatment plants, fish farms, civil sites or basements where flooding is concerned, a non-blocked water slurry pump is installed to discharge water and slurry to the outside.

Unlike general pumps that pump pure liquid fluids, non-clogged submersible slurry pumps have to transport liquids that contain a large number of solid particles, so they are much less efficient than centrifugal pumps that carry only pure liquids. type pump) is mainly used.

In order to overcome this problem, there is a method of using a relatively high-efficiency centrifugal pump, but due to the characteristics of the slurry pump to transport solids together, clogging occurs in the pump, so that stable pumping is impossible. Frequent maintenance will increase maintenance costs and reduce uptime, as well as overload, leading to failure of main transmission system components and reduced durability.

Accordingly, there is a demand for the development of an impeller design technology capable of improving efficiency in a wide operating range while minimizing clogging in a centrifugal pump. In relation to the impeller design, particularly in the case of slurry pumps, efficient operation is required even at a low specific speed depending on the intended use, but the efficiency of the centrifugal pump decreases rapidly with the decrease of the specific speed. When designing and manufacturing a low specific speed pump with the design method of, the impeller flow path is very narrow, and it is impossible to transport relatively large solids.

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above, and an object thereof is to provide a pump impeller which minimizes clogging during slurry transfer and enables efficient operation even at a low specific speed.

In order to achieve the above object, the pump impeller according to the present invention is a suction surface wing formed in the suction region of the object to be sucked from the center of the hub, and discharged to extend in the end of the suction surface wing portion is formed in the discharge region of the object to be sucked In the pump impeller having a blade made of a surface wing, the angle of placement (θ (r)) of the suction surface wing is formed to satisfy the following equation, the torsion angle β of the suction surface wing is 26 ~ The angle specified in the 34 ° range is characterized in that it is formed to have the same value in all areas.

(R _i in the above equation represents the radius of the starting point of the suction surface blade, the torsion angle β is a line (a) orthogonal to the curvature radius (r) direction of the suction surface blade, and the suction surface The angle between the tangent (b) of the wing, ln is the natural log (log _e ).)

The blades may be configured in pairs symmetrically from a central protrusion of the hub. At this time, the torsion angle β of the suction surface wing portion may be configured to 30 °.

On the other hand, the forming angle (α) of the blade is characterized in that consisting of 325 ~ 370 ° range.

In order to achieve the above object, the pump impeller according to the present invention is a suction surface wing formed in the suction region of the object to be sucked from the center of the hub, and discharged to extend in the end of the suction surface wing portion is formed in the discharge region of the object to be sucked In the pump impeller having a blade made of a surface wing, the placement angle (θ (r)) of the suction surface wing is formed to satisfy the following equation, the torsion angle β of the suction surface wing is 21.5 ~ The angle specified in the 23.5 ° range is formed to have the same value in all areas, the forming angle (α) of the blade is characterized in that it is formed in the range of 260 ~ 290 °.

(R _i in the above equation represents the radius of the starting point of the suction surface blade, the torsion angle β is a line (a) orthogonal to the curvature radius (r) direction of the suction surface blade, and the suction surface The angle between the tangent (b) of the wing, ln is the natural log (log _e ).)

In this case, the blade may be configured in pairs symmetrically from the central protrusion of the hub.

The pump impeller of the present invention, the pump efficiency by forming the incidence plane twist angle (β) of the braid over the entire area at an angle selected from 26 to 34 ° range and the overall forming angle (α) of the blade to 325 to 370 ° Since the pump can be closer to or higher than 60%, the pump efficiency can be significantly improved compared to the conventional centrifugal pump efficiency of about 50%. In addition, by forming a structure having two blades, clogging may be minimized during the transfer of the slurry, and an efficient operation may be performed even at a low specific speed.

In addition, the torsion angle β of the braid is formed over the entire area at an angle selected from the range of 21.5 to 23.5 °, and the overall formation angle α of the blade is formed to be in the range of 260 to 290 °. It is possible to implement a pump having a high level of pump efficiency of about 55% even at a small level of forming angle α of the blade.

1a to 1b is a view for explaining the external structure of the pump impeller according to an embodiment of the present invention,
2 is a cross-sectional view showing a pump impeller according to an embodiment of the present invention;
Figure 3 shows a grating of the impeller for the simulation of the pump impeller according to the invention,
Figure 4 is a view showing the impeller shape modeled to determine the effect of the torsion angle β of the inlet blade portion on the pump performance in the pump impeller according to the present invention,
5 is a view showing the pressure distribution and the velocity vector pattern on the meridion surface according to the change of the torsion angle β in the pump impeller according to the present invention;
6 is a graph showing the effect of the change of the torsion angle (β) on the pump efficiency as an analysis result according to the change of the torsion angle (β) in the pump impeller according to the present invention,
7 is a graph showing another example of the change in the torsion angle β in the pump impeller according to the present invention;
8 is a graph showing the effect of the change of the torsion angle β on the pump efficiency as an analysis result according to the change of the torsion angle β as shown in FIG.
9 is a view showing the impeller shape according to the change in α value for determining the length of the blade in the pump impeller according to the present invention;
10A and 10B are graphs showing the effect of the change in the overall blade forming angle α and the torsion angle β on the pump efficiency;
11 is a view showing the pressure distribution and the velocity vector pattern on the meridion surface according to the change of the forming angle α of the blade in the pump impeller according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1a to 1b is a view for explaining the external structure of the pump impeller according to an embodiment of the present invention, Figure 2 is a cross-sectional view showing a pump impeller according to an embodiment of the present invention, Figure 1a shows a pump impeller 1B is a perspective view showing a state where the pump impeller is installed in the pump housing, and FIG. 2 shows a simplified cross section for better understanding.

1A to 2, a pump impeller 10 according to an embodiment of the present invention is inserted into a pump housing 20 and connected to a lower end of a motor shaft (not shown) of a pump while being rotated by a driving force of a motor. A hub 11 corresponding to a body portion of the impeller 10 and a plurality of formed in the hub 11 are configured to suck the sucked object from the suction port 21 and discharge the discharged object toward the discharge port 22 side. Blade 12 is provided.

Although the hub 11 is not limited in shape, in the present embodiment, the hub 11 has a substantially conical shape but is recessed so that its outer circumferential surface has a predetermined radius of curvature inward, so that the central protrusion 111 is formed at the center thereof. In addition, a shroud 30 is formed at a position facing the outer circumferential surface of the hub 11 in a diagonal direction to form a flow passage having an approximately elbow shape between the outer circumferential surface of the hub 11 and the shroud 30. In this case, the shroud 30 may be configured as a separate independent member as shown in Figure 1b is mounted on the pump housing 20, or may be configured to be integrally formed with the hub (11).

The blade 12 may be configured in various ways in one or more according to the size of the solids contained in the liquid, in this embodiment, the width of the flow path and the outlet in the impeller 10 is formed to be wide, the slurry (liquid containing solids) It is formed in a structure having two blades 12 so as to easily pump).

The blade 12 extends integrally with the suction surface vane 121 formed in the suction region of the object to be sucked from the center of the hub 11 and the end of the suction surface wing 121 to discharge the suction object. The discharge surface wing portion 122 is formed in the area.

On the other hand, the conventional research and development activities for implementing the impeller to improve the efficiency of the pump was mainly related to the discharge surface wing 122, in this embodiment variously modeled around the suction surface wing 121 And interpret and implement it.

In the present embodiment, the placement angle θ (r) of the suction surface vane 121 is formed to satisfy the following Equation 1, but the torsion angle β is formed to be in the range of 26 to 34 °. The torsion angle specified within the range is formed to have the same value in the whole area. At this time, the forming angle (α) of the blade is formed to be in the range of 325 ~ 370 °. In this case, α denotes a blade length angle of the blade.

Here, r _i in the equation represents the radius of the starting point of the suction surface blade 121, the torsion angle β is a line orthogonal to the curvature radius (r) direction of the suction surface blade 121 The angle between (a) and the tangent (b) of the said suction surface wing part is shown, and ln is a natural log (log _e ).)

On the other hand, as a modified example of the present embodiment, the placement angle θ (r) of the suction surface wing portion 121 is formed to satisfy the above Equation 1, and the torsion angle β is 21.5 to 23.5 ° in all areas. It is formed in a range, in this case, the forming angle (α) of the blade is formed to be in the range of 260 ~ 290 °.

Hereinafter, the pump impeller 10 according to the present embodiment will be described in detail through specific modeling and numerical analysis.

First, in the impeller shape design that has an absolute effect on the performance of the pump, as shown in Figures 1a to 2, the meridional view (m; meridional view) representing the basic shape of the blade 121 is applied to the three-dimensional surface of the blade Suction diameter (2xDi), outlet height (Ho), and hub (11) and shroud (30) curves, which constitute physical properties based on a virtual two-dimensional plane), are important design variables. In addition, in the front view, two twist angles representing the blade twist, that is, the above-described twist angle (β) and the angle angle (θ) are very important design variables. In particular, in the case of the non-clog centrifugal pump, blade twist exists in the inlet area as well as the meridian (m), unlike the general centrifugal pump, and this part is very sensitive to performance.

In consideration of this, in the present embodiment, the relationship of Equation 2 below is established according to the radius of curvature r between θ (r) and β (r) among design variables for determining blade twist, and β in all areas If has a constant value to satisfy the above equation (1). In the present analysis, the pump impeller is configured as shown in Table 1 below, and the hub 11 and shroud 30 curves forming the suction diameter, the exit height Ho, and the interface based on the meridion plane m are bounded. To be given as a condition.

Component parts

standard Flow rate 3 m ³ / min Impeller inlet inner diameter 34 mm Impeller inlet outer diameter 180 mm Impeller outlet diameter 236 mm Impeller outlet height 67 mm

In addition, the three-dimensional shape of the pump impeller 10 is designed and generated according to the constraints and boundary conditions and values of design variables given using a 3-D shape implementation program (eg, ANSYSCFX-BaldeGen program), and used for analysis. As shown in Fig. 3, tetrahedral lattice was mainly used, and the analysis was performed only on one of the two blades in consideration of the calculation time.The numerical analysis was performed using a commercial analysis program and the working fluid was verified after the prototype was manufactured. Water was used for the procedure. In the analysis process, the boundary condition was a pressure of 1 bar at the inlet side and a flow rate of ³ m ³ / min at the outlet side, and the rotation speed was 1750 rpm.

On the other hand, Figure 4 is a view showing the impeller shape modeled to see the effect of the torsion angle (β) of the inlet blade wing on the pump performance in the pump impeller according to the present invention, wherein, the angle of formation of the blade of each pump impeller (α) is set to 370 °, and the torsion angle (β) is different to 22.5 °, 27 °, 30 °, and 33 °, but are formed so as to have the same value in the entire area, respectively, looking at the blade of Figure 4 It can be seen that as the angle β increases, the entrance wing 121 is gradually opened and increased.

5 is a diagram showing the pressure distribution on the meridion surface and the velocity vector pattern according to the change of the torsion angle β in the pump impeller according to the present invention, and the left side shows the pressure distribution on the meridion surface according to the change of the torsion angle β. It is shown by the contour line, and the right side shows the velocity vector pattern on the meridian according to the change of the torsion angle β.

Referring to the pressure distribution pattern of FIG. 5, the blade of the pump impeller has a twist angle β of 22.5 ° and 27 when the angle of formation α of the blade of the inlet blade 121 has a constant value of 370 °. When changing in the order of °, 30 °, and 33 °, the pressure at the meridion plane (m) is the inlet outer pressure (i1) with a torsion angle (β) of 22.5 °, as can be seen from the contour distribution. Although very high, it can be seen that the inlet side pressures i1, i2, i3, i4 are gradually evenly distributed in the order of 27 °, 30 °, and 33 °.

Referring to the velocity vector pattern of Fig. 5, the inlet outer surface portion i1 having a torsion angle β of 22.5 ° is formed with a very high pressure, which results in the working fluid to be sucked into the flow path being pushed out. It can be seen that the efficiency of the pump is lowered. In contrast, the inlet outer surface portions i3 and i4 having torsion angles β of 30 ° and 33 ° have a low pressure and are formed at a pressure similar to that of the inlet side, so that the working fluid to be sucked is not pushed out. It can be seen that the side moves smoothly. The reason is that when the torsional angle β increases, the inlet side outer surface, which is in contact with the working fluid at a relatively high speed, increases and decreases, thereby sufficiently transferring energy to the working fluid.

Figure 6 is a graph showing the effect of the change of the torsion angle (β) on the pump efficiency as an analysis result according to the change of the torsion angle (β) in the pump impeller according to the present invention.

The pump efficiency (total efficiency) is a percentage defined by Equation 3, as is well known. Referring to FIG. 5, the pump efficiency also gradually increases when the torsion angle β is increased. have. The reason is that, as shown in Fig. 5, when the torsion angle β of the inlet blade increases, the outer surface portion of the inlet surface which contacts the working fluid increases at a relatively high speed, and thus the energy is sufficiently transferred to the working fluid. The fluid can be drained quickly. However, when the torsion angle (β) is 30 ° or more it can be seen that the pump efficiency is lowered due to the increased frictional force.

Where r is the specific weight, Q is the flow rate, H is the head, and P _shaft is the shaft power.

Figure 7 is a graph showing another example of the change in the torsion angle (β) in the pump impeller according to the present invention, where the torsion angle (β) as shown in Figure 4 in addition to having the same value in the entire region (βin = βout) Various shapes varying from the start point βin of the entrance face wing 121 to the end point βout position are shown. That is, as can be seen through the internal coordinates of FIG. 7, the torsion angle β is varied in an arrangement angle θ of the entrance face wings 121 in a range of 22.5 ° to 30 °.

FIG. 8 is a graph showing the effect of the change of the torsion angle β on the pump efficiency as a result of the analysis according to the change of the torsion angle β as shown in FIG. 7. Referring to this, the shape of the inlet blade 121 is It can be seen that the highest efficiency is obtained when the torsion angle β has a constant value of 30 °.

9 is a view showing the impeller shape according to the change of the α value for determining the length of the blade in the pump impeller according to the present invention, as shown in this the overall forming angle (α) of the blade 12 is α = 280 ° It can be seen that, in the order of α = 325 ° and α = 370 °, the length of the blade also increases and increases.

10A and 10B are graphs showing the effect of the change in the overall blade forming angle (α) and the torsion angle (β) on the pump efficiency. Referring to this, the blade overall forming angle (α) is in the range of 325 ° to 370 °. The pump efficiency tends to increase in proportion to the torsion angle β, but it can be seen that the pump efficiency decreases when the overall blade forming angle α is 280 ° or less. That is, when the length of the blade 12 is long, the pump efficiency is increased in proportion to the torsion angle β, but when the length of the blade is short it can be seen that the pump efficiency is lowered. This is because, when the blade length is relatively short, a situation in which the working fluid cannot be pushed in sufficiently is caused, resulting in a situation in which the inflow of fluid from the inlet side is blocked.

In addition, referring to FIG. 10A, when the overall formation angle α of the blade is 370 ° and the torsion angle β is in the range of 26 to 34 °, the pump efficiency is 60% or more, and the overall formation angle of the blade 12 is shown. When (α) is 325 ° and the torsion angle (β) is in the range of 30 to 34 °, it can be seen that the pump efficiency is expressed as an efficiency close to 60%. This pump efficiency can be seen that the pump efficiency is significantly improved to a very high level considering that the typical centrifugal pump efficiency is about 50%.

On the other hand, the coordinates shown in the left part of Figure 10b is a point where the torsion angle (β) and the overall forming angle (α) of the blade is small, the pump efficiency is expected to be relatively low, the torsion angle (β) in the range of 21.5 ~ 23.5 ° Selected and formed at the same angle in the entire region (βin = βout), the region where the blade forming angle (α) of 260 ~ 290 ° range shows that the pump efficiency is around 55%, this level of Pump efficiency is also relatively high considering the centrifugal pump efficiency of about 50%. In particular, it is remarkable that the pump efficiency is high even though the torsion angle β and the blade formation angle α are small, and it is noteworthy that this unique feature can be used to design an impeller suitable for a specific purpose or application. Can be.

11 is a view showing the pressure distribution and the velocity vector pattern on the meridian according to the change of the blade forming angle α in the pump impeller according to the present invention, the left side of the pump impeller according to the change of the blade forming angle α on the meridion surface. The pressure distribution of is shown by the contour line, and the right side shows the velocity vector pattern on the meridional surface according to the change of the forming angle (alpha) of the blade.

Referring to the pressure distribution patten of FIG. 11, the blade 12 of the pump impeller 10 has the blade forming angle α when the torsion angle β of the inlet blade 121 has a constant value of 30 °. ), The pressure at the meridional surface (m) can be seen from the distribution of contours, and the inlet outer surface (j1) pressure with the blade forming angle (α) of 280 ° Although very high, the inlet-side outer surface j3 pressure at which the blade forming angle α is 370 ° is formed to be close to the pressure of the inlet-side inner surface.

Referring to the velocity vector pattern of FIG. 11, the inlet outer surface portion j1 having the blade forming angle α of 280 ° is formed with a very high pressure, and the working fluid to be sucked into the flow path is rather pushed out. It can be seen that the efficiency of the pump is lowered. In contrast, the blade forming angle α is 370 ° and the inlet side outer portion j3 has a low pressure and is formed at a pressure close to that of the inlet side, so that the working fluid to be sucked is smoothly moved to the outlet side without being pushed out. It can be seen that.

As a result, as described above, the pump impeller has a torsion angle β of the suction surface wing of about 30 ° and a blade forming angle α of about 325 to 370 ° so that the pump efficiency approaches 60%. High efficiency pump can be implemented.

What has been described above is only one embodiment for implementing the pump impeller according to the present invention, the present invention is not limited to the above-described embodiment, it does not depart from the gist of the present invention as claimed in the following claims Any person with ordinary skill in the art to which the present invention pertains will be within the scope of the technical idea of the present invention to the extent that various modifications can be made.

10: pump impeller 11: hub
12: blade 121: entrance wing
122: discharge side wing 20: pump housing
21: inlet 22: outlet
30: shroud α: angle of formation of the blade
β: Suction angle of wing surface twist angle θ: Suction surface wing angle arrangement angle

Claims (6)

In the pump impeller having a blade comprising a suction surface wing formed in the suction region of the object to be sucked from the center of the hub, and a discharge surface wing portion extending to an end of the suction surface wing and formed in the discharge region of the object to be sucked,
Arrangement angle θ (r) of the suction surface wing is formed to satisfy the following equation,
Torsion angle (β) of the wing surface wing portion is characterized in that the pump impeller is formed so that the angle specified in the range of 26 ~ 34 ° has the same value in the entire area.

(R _i in the above equation represents the radius of the starting point of the suction surface blade, the torsion angle β is a line (a) orthogonal to the curvature radius (r) direction of the suction surface blade, and the suction surface The angle between the tangent (b) of the wing, ln is the natural log (log _e ).)
The method of claim 1,
And the blades are configured in pairs symmetrically from a central protrusion of the hub.
The method of claim 2,
Pump impeller, characterized in that the torsion angle β of the suction surface wing portion is 30 °.
4. The method according to any one of claims 1 to 3,
Forming angle (α) of the blade is a pump impeller, characterized in that the range of 325 ~ 370 °.
In the pump impeller having a blade comprising a suction surface wing formed in the suction region of the object to be sucked from the center of the hub, and a discharge surface wing portion extending to an end of the suction surface wing and formed in the discharge region of the object to be sucked,
Arrangement angle θ (r) of the suction surface wing is formed to satisfy the following equation,
The torsion angle β of the suction surface wing is formed such that the angle specified in the range of 21.5 to 23.5 ° has the same value in all areas,
Forming angle (α) of the blade is a pump impeller, characterized in that formed in the range of 260 ~ 290 °.

(R _i in the above equation represents the radius of the starting point of the suction surface blade, the torsion angle β is a line (a) orthogonal to the curvature radius (r) direction of the suction surface blade, and the suction surface The angle between the tangent (b) of the wing, ln is the natural log (log _e ).)
The method of claim 5,
And the blades are configured in pairs symmetrically from a central protrusion of the hub.

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