A single-sided double-suction impeller structure

Abstract

The application relates to a single-side double-suction impeller structure, which comprises a cover plate, a plurality of front blades arranged on the front surface of the cover plate and a plurality of back blades arranged on the back surface of the cover plate, wherein the profile lines of the front blades and the back blades are the same; a plurality of flow distribution channels are arranged on the cover plate and are arranged in a circumferential interval around the center of the cover plate, each flow distribution channel is arranged at the inlet of the front blade and the back blade, and each flow distribution channel is arranged between two adjacent front blades and two adjacent back blades. The single-side double-suction impeller structure can realize the function of single-side double suction, has good cavitation resistance and axial force balance, and has a simple and compact structure.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of impeller structures, in particular to a single-side double-suction impeller structure. BACKGROUND

[0002] In the field of centrifugal pumps, single-stage single-suction impellers and single-stage double-suction impellers are two common impeller types, the single-stage single-suction impeller is simple in structure, but is poor in anti-cavitation performance and axial force balance under large-flow working conditions. The single-stage double-suction impeller is good in flow stability and structural stability and anti-cavitation performance, but the suction section structure is relatively complex.

[0003] In the related art, in the fields of aerospace, ocean engineering and the like, good anti-cavitation performance and axial force balance are basic on fuel supply, hydraulic medium circulating equipment and the like, but the requirement of simple and compact structure needs to be considered, therefore, a single-side double-suction impeller structure is provided. SUMMARY

[0004] In order to realize the simple and compact structure, the application provides a single-side double-suction impeller structure.

[0005] The single-side double-suction impeller structure provided by the application adopts the following technical scheme:

[0006] A single-side double-suction impeller structure, comprising a cover plate, a plurality of front face blades arranged on the front face of the cover plate, and a plurality of back face blades arranged on the back face of the cover plate, wherein the profile lines of the front face blades and the back face blades are the same.

[0007] A plurality of flow distribution channels are arranged on the cover plate, the plurality of flow distribution channels are arranged circumferentially and spaced apart around the center of the cover plate, each flow distribution channel is arranged at the inlet of the front face blade and the back face blade, and each flow distribution channel is arranged between two adjacent front face blades and two adjacent back face blades.

[0008] Preferably, a plurality of flow guide channels are arranged on the cover plate, the plurality of flow guide channels are arranged circumferentially and spaced apart around the center of the cover plate, each flow guide channel is communicated with each flow distribution channel, and a flow guide plate is arranged in each flow guide channel.

[0009] Preferably, an inclined flow guide slope is formed on the flow guide plate, which is inclined to the side of the back face blade.

[0010] Preferably, the flow guide channel and the flow distribution channel are both arranged in a fan shape, and the radii of the upper arc line and the lower arc line of the flow guide channel and the flow distribution channel are the same.

[0011] Preferably, the distance between the upper arc line of the flow distribution channel and the end of the inlet of the front face blade and the back face blade is 3-5 mm.

[0012] Preferably, the upper arcs of all the flow guide channels and the flow distribution channels are closed to form a circle with a diameter close to the diameter of the water inlet formed by the front blades.

[0013] Preferably, the front flow of the single-sided double-suction impeller structure is q1, the back flow of the single-sided double-suction impeller structure is q2, and q2=kq1 is configured in the single-sided double-suction impeller structure, wherein k is a constant, and k=0.2-0.7.

[0014] The back flow q2 of the single-sided double-suction impeller structure is nsv, wherein n is the number of flow distribution channels, s is the effective flow area of the flow distribution channel, and v is the flow velocity of the flow distribution channel.

[0015] The effective flow area s of the flow distribution channel is wd, wherein w is the width of the flow distribution channel, and d is the thickness of the cover plate.

[0016] The flow velocity v of the flow distribution channel is (3.14*n*C*R) / 30, wherein n is the number of flow distribution channels, C is a correction coefficient, C=1-1.3, and R is the center line radius of the flow distribution channel.

[0017] Preferably, the front flow channel is formed between adjacent front blades, the back flow channel is formed between adjacent back blades, and the flow cross-sectional area of the back flow channel is 0.3-0.8 times the flow cross-sectional area of the front flow channel.

[0018] Preferably, the cover plate is provided with a splitter blade between adjacent back blades, and the inlet position of the splitter blade is located at one-third of the back flow channel.

[0019] Preferably, the splitter blade divides the back flow channel into two flow distribution channels, and the cover plate is provided with at least one communication hole in the flow distribution channel.

[0020] In summary, the present application has at least one of the following beneficial technical effects:

[0021] The single-sided double-suction impeller structure can realize the function of single-sided double-suction, ensure good anti-cavitation and axial force balance, and has a simple and compact structure. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a schematic diagram of the installation of the single-sided double-suction impeller structure.

[0023] Figure 2 is a first arrangement schematic diagram of the front blade.

[0024] Figure 3is a schematic view of the arrangement of the back vanes.

[0025] Figure 4 is a schematic view of the structure of the distribution channel.

[0026] Figure 5 is a schematic view of the second arrangement of the front vanes.

[0027] Figure 6 is a schematic view of the height of the front vanes and the back vanes.

[0028] BRIEF DESCRIPTION OF REFERENCE NUMERALS: 1, cover plate; 2, front vane; 3, back vane; 4, mounting shaft hole; 5, distribution channel; 6, flow guide channel; 7, flow guide plate; 8, shunt vane; 9, communication hole. DETAILED DESCRIPTION

[0029] The following will be described in detail below with reference to the accompanying drawings. Figures 1-6 The present application will be described in further detail.

[0030] A single-sided double-suction impeller structure, as shown in the accompanying drawings, is applied to a semi-open impeller structure or a closed impeller structure, can realize the function of single-sided double-suction, and simultaneously performs targeted design on the vane structure to realize the effect of complete balance of axial forces on both sides. Figure 1

[0031] Specifically, as shown in the accompanying drawings, Figure 2 Figure 3 Figure 4 The single-sided double-suction impeller structure includes a cover plate 1, a plurality of front vanes 2 arranged on the front of the cover plate 1, and a plurality of back vanes 3 arranged on the back of the cover plate 1. The middle part of the cover plate 1 is a mounting shaft hole 4. In one embodiment, the mounting shaft hole 4 is a spline hole. In another embodiment, a flat key groove is formed on the mounting shaft hole 4. The impeller can be assembled onto the water pump main shaft through the mounting shaft hole 4.

[0032] The profile lines of each front vane 2 and each back vane 3 are the same. The plurality of front vanes 2 are distributed in a vortex shape around the mounting shaft hole 4 in the center of the cover plate 1. The plurality of back vanes 3 are distributed in a vortex shape around the mounting shaft hole 4 in the center of the cover plate 1. One end of all the front vanes 2 and all the back vanes 3 close to the mounting shaft hole 4 is an inlet. The other end of all the front vanes 2 and all the back vanes 3 is flush with the outer edge of the cover plate 1.

[0033] A plurality of distribution channels 5 are formed on the cover plate 1. The distribution channels 5 penetrate the cover plate 1 along the axial direction. The plurality of distribution channels 5 are arranged in a circumferential direction around the center of the cover plate 1. Each distribution channel 5 is arranged at the inlet of the front vane 2 and the back vane 3. Each distribution channel 5 is arranged between two adjacent front vanes 2 and two adjacent back vanes 3.

[0034] ​​​Wherein, the cover plate 1 is provided with a plurality of drainage channels 6, the plurality of drainage channels 6 are arranged in a circumferential interval around the center of the cover plate 1, each of the drainage channels 6 is communicated with each of the distribution channels 5, so as to Figure 2 For reference direction, the drainage channel 6 is arranged at the left side of the distribution channel 5, the drainage plate 7 is arranged in each of the drainage channels 6, the drainage plate 7 fills the whole drainage channel 6, the right side edge of the drainage plate 7 is connected with the distribution channel 5, and the drainage inclined surface is formed on the drainage plate 7 and inclined to the back vane 3 side of the distribution channel 5. Thus, the water body can be guided into the distribution channel 5 through the drainage plate 7 in the drainage channel 6, so as to realize that part of the water body enters the back of the cover plate 1 from the front of the cover plate 1.

[0035] The drainage channel 6 and the distribution channel 5 are arranged in a fan shape, and the radii of the upper arc line and the lower arc line of the drainage channel 6 and the distribution channel 5 are the same. Wherein, the distance between the upper arc line of the distribution channel 5 and the end of the inlet of the front vane 2 and the back vane 3 is 3-5mm, preferably, the distance between the upper arc line of the distribution channel 5 and the end of the inlet of the front vane 2 and the back vane 3 is 4mm.

[0036] The upper arc lines of all the drainage channels 6 and the distribution channels 5 are surrounded to form a circular diameter close to the water inlet diameter surrounded by the front vane 2, wherein close means that the circular diameter surrounded by the upper arc lines of all the drainage channels 6 and the distribution channels 5 is 1-3mm smaller than the water inlet diameter surrounded by the front vane 2, preferably 2mm.

[0037] Through the arrangement of the distribution channel 5, the front of the cover plate 1 and the back of the cover plate 1 are communicated, part of the water body is discharged through the front vane 2, and another part of the water body enters the back of the cover plate 1 through the distribution channel 5 and is discharged through the back vane 3, so as to realize the single-sided double-suction impeller structure.

[0038] The front flow and the back flow of the single-sided double-suction impeller structure are designed as follows.

[0039] The front flow of the single-sided double-suction impeller structure is q1, the back flow of the single-sided double-suction impeller structure is q2, and q2=kq1 is configured in the single-sided double-suction impeller structure, wherein k is a constant, k=0.2-0.7.

[0040] The back flow q2 of the single-sided double-suction impeller structure is nsv, wherein n is the number of the distribution channels 5, s is the effective flow area of the distribution channel 5, and v is the flow velocity of the distribution channel 5.

[0041] The effective flow area s of the distribution channel 5 is wd, wherein w is the width of the distribution channel 5, and d is the thickness of the cover plate 1.

[0042] The flow velocity of distribution channel 5 is v = (3.14 * n * C * R) / 30, where n is the number of distribution channels 5, C is a correction coefficient, C = 1 to 1.3, and R is the centerline radius of distribution channel 5.

[0043] A front flow channel is formed between adjacent front blades 2, and a back flow channel is formed between adjacent back blades 3. To achieve the same pressure gradient between the front blades 2 and the back blades 3, their profiles are identical. However, the front flow rate is smaller than the back flow rate. To reduce axial vortices in the distribution channel 5 and improve efficiency, the cross-sectional area of ​​the back flow channel is reduced. In one embodiment, the cross-sectional area of ​​the back flow channel is 0.3 to 0.8 times that of the front flow channel, and preferably 0.5 times.

[0044] It is worth noting that the cover plate 1 has a diversion blade 8 between adjacent back blades 3. The inlet of the diversion blade 8 is located at one-third of the back flow channel, and the inlet angle of the diversion blade 8 is (20°~29°)-C, where C=(2°-5°). The diversion blade 8 divides the back flow channel into two diversion channels, and the cover plate 1 has at least one connecting hole 9 in each diversion channel. In this embodiment, each diversion channel has two connecting holes 9. The connecting holes 9 can further eliminate residual axial force. The connecting holes 9 are arranged on both sides of the diversion blade 8, which can achieve pressure balance on both sides of the diversion blade 8.

[0045] The following settings are made for the front blade 2 and the back blade 3.

[0046] Reference Figure 5 and Figure 6 As shown, the inlet placement angle a1 of the front blade 2 is (19°-35°)-C1, where C1=2°-5°, the wrap angle b of the front blade 2 is (110°-150°)+C2, where C2=(2°-5°), and the inlet velocity u1 of the front blade 2 is πD1n1 / 60, where D1 is the inlet diameter of the front blade 2, and the inlet of the front blade 2 refers to the inlet formed by the ends of all the front blades 2, and n1 is the number of front blades 2.

[0047] The exit height of the front blade 2 is h1 = K b (2gH) 1 / 2 / n1, where K b These are correction parameters, where H is the pump head and n1 is the number of front blades 2.

[0048] In the front blade 2 design, the front blade 2 inlet height is higher than the front blade 2 outlet height, the back blade 3 outlet height h2 is lower than the front blade 2 outlet height h1, and the back blade 3 inlet height is lower than the back blade 3 outlet height h2.

[0049] In order to further improve the anti-cavitation, the single-sided double-suction impeller structure of the application can be used in combination with an inducer, the inducer is arranged on the front side of the single-sided double-suction impeller, the blade outlet angle in the inducer is close to the inclination angle of the flow guide plate 7, so that Figure 5 The blade outlet edge in the inducer is offset by 3-5° to the left in the circumferential direction of the distribution passage 5 as a reference angle.

[0050] Therefore, by arranging the single-sided double-suction impeller structure, the impeller structure can realize the function of single-sided double-suction, and the anti-cavitation and axial force balance are ensured under the premise of simple and compact structure.

[0051] The above are preferred embodiments of the application, and are not intended to limit the protection scope of the application, therefore: any equivalent changes made on the structure, shape and principle of the application should be covered within the protection scope of the application.

Claims

1. A single-sided double-suction impeller structure, characterized in that, It includes a cover plate (1), a plurality of front blades (2) disposed on the front side of the cover plate (1), and a plurality of back blades (3) disposed on the back side of the cover plate (1), wherein the front blades (2) and the back blades (3) have the same profile. The cover plate (1) is provided with a plurality of flow distribution channels (5), and the plurality of flow distribution channels (5) are arranged circumferentially around the center of the cover plate (1). Each flow distribution channel (5) is located at the inlet of the front blade (2) and the back blade (3), and each flow distribution channel (5) is located between two adjacent front blades (2) and two adjacent back blades (3). The front flow rate of the single-sided double-suction impeller structure is q1, the back flow rate of the single-sided double-suction impeller structure is q2, and the single-sided double-suction impeller structure is configured with q2=kq1, where k is a constant, k=0.2~0.7; The back flow rate of the single-sided double suction impeller structure is q2=nsv, where n is the number of distribution channels (5), s is the effective flow area of ​​the distribution channel (5), and v is the flow velocity of the distribution channel (5). The effective flow area of ​​the distribution channel (5) is s=wd, where w is the width of the distribution channel (5) and d is the thickness of the cover plate (1). The flow velocity of the distribution channel (5) is v = (3.14 * n * C * R) / 30, where n is the number of distribution channels (5), C is a correction coefficient, C = 1 ~ 1.3, and R is the center line radius of the distribution channel (5).

2. The single-sided double-suction impeller structure according to claim 1, characterized in that, The cover plate (1) is provided with a plurality of drainage channels (6), and the plurality of drainage channels (6) are arranged circumferentially around the center of the cover plate (1). Each drainage channel (6) is connected to each distribution channel (5), and each drainage channel (6) is provided with a drainage plate (7).

3. The single-sided double-suction impeller structure according to claim 2, characterized in that, The flow guide plate (7) has a flow guide slope that is inclined toward the back blade (3) towards the flow distribution channel (5).

4. The single-sided double-suction impeller structure according to claim 2, characterized in that, Both the diversion channel (6) and the distribution channel (5) are arranged in a fan shape, and the upper and lower arcs of the diversion channel (6) and the distribution channel (5) have the same radius.

5. The single-sided double-suction impeller structure according to claim 4, characterized in that, The distance between the upper arc of the distribution channel (5) and the end of the inlet of the front blade (2) and the back blade (3) is 3-5 mm.

6. The single-sided double-suction impeller structure according to claim 4, characterized in that, The diameter of the circle formed by the upper arcs of all the drainage channels (6) and the distribution channels (5) is close to the diameter of the inlet formed by the front blades (2).

7. The single-sided double-suction impeller structure according to claim 1, characterized in that, A front flow channel is formed between adjacent front blades (2), and a back flow channel is formed between adjacent back blades (3). The flow cross-sectional area of ​​the back flow channel is 0.3 to 0.8 times that of the front flow channel.

8. The single-sided double-suction impeller structure according to claim 7, characterized in that, The cover plate (1) has a diversion blade (8) between adjacent back blades (3), and the inlet of the diversion blade (8) is located at one-third of the back flow channel.

9. A single-sided double-suction impeller structure according to claim 8, characterized in that, The flow divider blade (8) divides the back flow channel into two flow divider channels, and the cover plate (1) has at least one connecting hole (9) in the flow divider channel.

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