CN208294833U

CN208294833U - Centrifugal pump impeller

Info

Publication number: CN208294833U
Application number: CN201721688557.4U
Authority: CN
Inventors: 蒋敦军; 林成波; 卢新全; 向宏杰
Original assignee: Shimge Pump Industry Group Co Ltd
Current assignee: Zhejiang Shimge Pump Co Ltd
Priority date: 2017-12-07
Filing date: 2017-12-07
Publication date: 2018-12-28
Anticipated expiration: 2027-12-07

Abstract

The utility model relates to a kind of centrifugal pump impellers, solve the problems, such as that hump is serious in the prior art, the technical solution of use: including front shroud, back shroud, the plural pieces blade that is set between front shroud and back shroud, it is characterised in that the outlet end of the blade opens up notch.Technical effect are as follows: under low flow rate condition, the distribution of impeller outlet fluid field pressure becomes more uniform, velocity gradient is also opposite to be reduced, compared to the impeller before cutting, it is obviously reduced at impeller outlet by VELOCITY DISTRIBUTION unevenness bring hydraulic blow loss, improves the value for shutting a lift H0 and its neighbouring lift, and be slightly decreased lift under big flow operating condition, the hump at small flow is eliminated, so that head curve trend becomes dropping suddenly.After to impeller outlet side progress semicircle or triangle cutting, it can effectively improve flow regime at impeller outlet, and very little is influenced on efficiency, improve the Stability and dependability of product operation, and it is low to cut convenience, manufacturing cost.

Description

Centrifugal pump impeller

Technical field

The utility model relates to a kind of centrifugal pump impeller more particularly to a kind of centrifugal pump impellers that can reduce hump.

Background technique

Centrifugal pump is widely used fluid machinery in liquid conveying, and the quality of performance will generate social economy important It influences.In real life, since there are design difficulties for pumps design problem or portioned product itself, inevitably (the main reason for hump occurs is to generate reflux when centrifugal pump operates in low flow rate condition to centrifugal pump lift curve hump Etc. a series of energy loss, lead to the reduction of low flow rate condition lift, and then hump phenomenon occur).Centrifugal pump lift curve has Hump (also known as unstable head curve) refers to after A point when H0 when its lift by flow Q is 0 rises to peak value Hmax again Decline, in region of the lift higher than H0, correspondingly there are two flow Q(is as shown in Figure 5 by each lift H).This lift camel Peak phenomenon is present in higher specific speed centrifugal pump, can also be present in low-specific-speed (specific speed is in 30~80 ranges), only exist Show more prominent in low-specific-speed, due to mostly using method of enlarged flow design to improve efficiency greatly when design, and water pump is real Border but operates in low flow rate condition, will generate biggish impact loss at this time, and biggish outlet blade angle is selected to go out with blade Mouth width degree etc., makes head curve be more prone to produce hump.

There is the centrifugal pump of hump for head curve, in some pump installations and many applications, such as boiler is with two When feed pump parallel pumping, it is easy to hour and big, Wu Fawen when so that water pump is generated overload and pipeline vibration, or generating flow Surely phenomena such as running.It will affect the normal conveying of liquid in this way, even influence normally produce, bring security risk sometimes.

Summary of the invention

A kind of centrifugal pump impeller is provided utility model aims to solve the above problem of the existing technology, leaf The outlet end of piece opens up notch, and under low flow rate condition, the distribution of impeller outlet fluid field pressure becomes more uniform, velocity gradient It is opposite to reduce, compared to the impeller before cutting, obviously subtracted at impeller outlet by VELOCITY DISTRIBUTION unevenness bring hydraulic blow loss It is small, the value for shutting a lift H0 and its neighbouring lift is improved, and be slightly decreased lift under big flow operating condition, eliminates small stream Hump at amount, so that head curve trend becomes dropping suddenly.

What the above-mentioned technical purpose of the utility model mainly solved by the following technical programs: centrifugal pump impeller, including Front shroud, back shroud, the plural pieces blade being set between front shroud and back shroud, it is characterised in that the outlet end of the blade Open up notch.The outlet end of blade opens up notch, and under low flow rate condition, the distribution of impeller outlet fluid field pressure becomes more Even, velocity gradient is also opposite to be reduced, and compared to the impeller before cutting, is rushed at impeller outlet by VELOCITY DISTRIBUTION unevenness bring waterpower It hits loss to be obviously reduced, improves the value for shutting a lift H0 and its neighbouring lift, and make under big flow operating condition lift slightly Decline, eliminates the hump at small flow, so that head curve trend becomes dropping suddenly, will not generate again to the whole efficiency of pump big It influences.

As further improving and supplementing to above-mentioned technical proposal, the utility model uses following technical measures:

The notch is semicircle, and the center of the notch is located at the midpoint of blade exit end outer.

The size of the radius R of the notch are as follows: R=(0.3~0.5) b2, b2 are the impeller outlet width.

The notch is triangle, and the bottom edge center of the notch of triangle is located in the outer of the blade exit end Point.

The size of the length b on the notch bottom edge are as follows: b=(0.4~0.6) b2, b2 is impeller outlet width.

The size of the apex angle α of the notch are as follows: α=100 °~130 °.

The utility model has the advantages that the outlet end of blade opens up notch, under low flow rate condition, impeller outlet Fluid field pressure distribution becomes more uniform, and velocity gradient is also opposite to be reduced, compared to the impeller before cutting, by speed at impeller outlet Degree is unevenly distributed bring hydraulic blow loss and is obviously reduced, and improves the value for shutting a lift H0 and its neighbouring lift, and It is slightly decreased lift under big flow operating condition, eliminates the hump at small flow, so that head curve trend becomes dropping suddenly.By right After impeller outlet side carries out the cutting of semicircle or triangle, flow regime at impeller outlet can effectively improve, and influence on efficiency Very little, improves the Stability and dependability of product operation, and it is low to cut convenience, manufacturing cost.

Detailed description of the invention

Fig. 1 is a kind of structural schematic diagram of the utility model.

Fig. 2 is another structural schematic diagram of the utility model.

Fig. 3 is the broken section structural schematic diagram of Fig. 1.

Fig. 4 is the broken section structural schematic diagram of Fig. 2.

Fig. 5 be the utility model relates to the prior art a kind of lift-flow curve figure.

Fig. 6 be the utility model relates to a kind of lift-flow curve figure.

Specific embodiment

Below with reference to the embodiments and with reference to the accompanying drawing the technical solutions of the present invention will be further described.

Embodiment: as shown in Figure 1, Figure 3, centrifugal pump impeller, including front shroud 1, back shroud 2, front shroud is set to after Plural pieces blade 3 between cover board, the outlet end of the blade open up notch 4.

The outlet end of blade opens up notch, and under low flow rate condition, the distribution of impeller outlet fluid field pressure becomes more uniform, Velocity gradient is also opposite to be reduced, compared to the impeller before cutting, by VELOCITY DISTRIBUTION unevenness bring hydraulic blow at impeller outlet Loss is obviously reduced, and improves the value for shutting a lift H0 and its neighbouring lift, and make under big flow operating condition lift slightly under Drop, eliminates the hump at small flow, so that head curve trend becomes dropping (as shown in Figure 6) suddenly, to the whole efficiency of pump and not Big influence can be generated.

To the further perfect of above-mentioned technical proposal: the notch 4 is semicircle, and the center of the notch is located at the leaf The midpoint of piece outlet end outer.

The cutting quantity of notch answers strict control within the above range, if the cutting quantity of notch is too small, at outlet of centrifugal pump The improvement result in flow field is smaller, and cutting purpose is not achieved；If the cutting quantity of notch is too big, can significantly affect at impeller outlet Energy increment, i.e., can reduce centrifugal pump lift, the reason is that can improve the pressure at impeller outlet behind cutting impeller outlet side really Or VELOCITY DISTRIBUTION situation, but the energy loss that this improvement result is reduced, impeller outlet side is much not achieved and is produced by cutting Raw fluid energy losses.

Embodiment 2: as shown in Figure 2 and Figure 4, the difference from embodiment 1 is that: the notch 4 is triangle, triangle The bottom edge center of the notch is located at the midpoint of blade exit end outer.

The size of the apex angle α of the notch are as follows: α=100 °~130 °.

The above descriptions are merely preferred embodiments of the present invention, is not intended to limit the utility model.Above-mentioned In embodiment, various modifications and changes may be made to the present invention.Within the spirit and principle of the utility model, made Any modification, equivalent substitution, improvement and etc. should be included within the scope of protection of this utility model.

Claims

1. centrifugal pump impeller, including front shroud, back shroud, the plural pieces blade being set between front shroud and back shroud is special Sign is that the outlet end of the blade opens up notch, and the notch is semicircle, and the center of the notch is located at the blade and goes out The midpoint of mouth end outer, the size of the radius R of the notch are as follows: R=(0.3~0.5) b2, b2 are the impeller outlet width, Alternatively, the notch is triangle, the bottom edge center of the notch of triangle is located at the midpoint of blade exit end outer, The size of the length b on the notch bottom edge are as follows: b=(0.4~0.6) b2, b2 is impeller outlet width.

2. centrifugal pump impeller according to claim 1, it is characterised in that the size of the apex angle α of the notch are as follows: α=100 ° ~130 °.