CN204878042U - Novel axial -flow impeller - Google Patents

Abstract

The utility model relates to a novel axial -flow impeller belongs to water conservancy power engineering design technical field, including the hub, evenly set up blade on the hub circumference, characterized by: the hub ratio of impeller is 0.4, and the hub diameter is 120mm, and diameter of impeller is 300mm, the apex cascade solidity 0.82 of blade, and blade root cascade solidity is 1.4 times of apex cascade solidity, the apex wing section is laid the angle and is 15.32. The quantity of blade is 4. The utility model discloses rational in infrastructure simple, manufacture easy, through the utility model discloses, not only the impeller efficiency ratio is higher for this axial -flow impeller, and the highest operation lift is bigger simultaneously. Be applied to renovating of pump station hydraulic model with this practicality is novel, it is applicable in the bigger axial compressor pump station of water -level fluctuation, the economic nature and the security of pump station operation can improve simultaneously.

Description

A New Axial Flow Impeller

technical field

The utility model relates to a novel axial-flow impeller, which belongs to the technical field of hydraulic power engineering design.

Background technique

At present, all countries in the world are developing high-efficiency axial-flow pump hydraulic models. my country has also done a lot of work in this area, and the efficiency of axial-flow pump impellers has generally been improved. However, the axial-flow pump impeller has been ignored while pursuing high efficiency. Economical and safe operation. As a result, the designed axial-flow impeller products cannot meet the requirements for maximum head operation, or the safety margin for maximum head operation is small, and the operation will enter the saddle area if the working conditions change slightly. At present, there is a lack of such hydraulic models of axial flow pumps in the series of domestic axial flow pumps.

Utility model content

The purpose of the utility model is to solve the problems in the prior art mentioned above, and provide a new type of axial flow impeller which can meet the operation requirements of the pumping station with a higher maximum operating head and at the same time have a relatively high efficiency under the design head.

The technical scheme of the utility model is a new axial flow impeller, including a hub and blades evenly arranged on the circumference of the hub, characterized in that: the hub ratio of the impeller is 0.4, the diameter of the hub is 120mm, and the diameter of the impeller is 300mm , the density of the blade tip cascade is 0.82, the density of the blade root cascade is 1.4 times that of the blade tip cascade, and the placement angle of the blade tip airfoil is 15.32°.

The number of the blades is 4 pieces.

The utility model has a reasonable and simple structure and is easy to manufacture. Through the utility model, the axial-flow impeller not only has relatively high impeller efficiency, but also has a relatively large maximum operating head. Applying the utility model to the updating and reforming of the hydraulic model of the pumping station, the utility model can be applied to the axial-flow pumping station with relatively large water level changes, and can improve the economy and safety of the pumping station's operation at the same time.

In this utility model, cascade denseness ( l /t) is an important parameter in the design of axial flow pump blades, l : refers to the chord length of the airfoil section; t=2πr/z, where z is the number of blades, r is the Radius value where the airfoil section is located. The blade tip cascade density refers to the cascade density of the airfoil section at the outermost edge of the blade, and the blade root cascade density refers to the cascade density of the airfoil section at the hub. The density of the root cascade is 1.4 times that of the tip cascade, that is, the density of the root cascade = the density of the tip cascade 0.82*1.4=1.148. The density of cascades in each section in the middle changes linearly from the blade tip to the blade root. The placement angle of the airfoil is the angle between the chord length of the airfoil of each section and the horizontal line.

The maximum lift of the impeller of the axial-flow pump of the utility model is relatively high, and the hydraulic model of the axial-flow impeller is suitable for pumping stations with relatively high requirements for water level changes at the lower and upper stations of the large-scale pumping stations of the South-to-North Water Diversion Project. The axial flow pump has a large head range and a wide high-efficiency zone, and the highest efficiency has exceeded the domestic first-line level. The maximum operating head of the axial flow impeller is relatively high, while taking into account the requirements of the highest efficiency.

With the construction of the east route project of the South-to-North Water Diversion Project and the implementation of the national large and medium-sized pumping station technical transformation, a total of hundreds of pumping stations need to be updated, and the requirements for the head range are getting higher and higher. Therefore, the application and implementation of this patent will be It will achieve greater economic and social benefits.

Description of drawings

Figure 1 is a three-dimensional modeling view of the axial flow impeller.

In the picture: 1 blade, 2 hubs.

Detailed ways

Below in conjunction with accompanying drawing and description of drawings, the utility model will be further described.

A new axial-flow impeller, including a hub 2, and blades 1 evenly arranged on the circumference of the hub 2, the number of blades 1 is 4, the hub ratio of the impeller is 0.4, the diameter of the hub 2 is 120mm, and the diameter of the impeller is 300mm.

The utility model adopts the means of multi-objective and multi-working condition optimization design to obtain an axial-flow impeller, and the impeller has a high operating head and high efficiency at the same time. Its main design parameters are: the density of the blade tip cascade of blade 1 is 0.82, the density of the blade root cascade is 1.4 times that of the blade tip cascade, and the placement angle of the blade tip airfoil is 15.32°.

The blade root cascade density is relatively high, and the blade root airfoil is longer, so as to ensure the same degree of energy conversion as the outer edge airfoil, balance the blade outlet lift, reduce radial flow, and improve efficiency. At the same time, CFD-based optimization is adopted The design increases the maximum operating lift.

Claims (2)

1. a Novel axial flow type impeller, comprise wheel hub (2), be evenly arranged on wheel hub (2) blade circumferentially (1), it is characterized in that: the hub ratio of described impeller is 0.4, wheel hub (2) diameter is 120mm, impeller diameter is 300mm, the blade tip cascade solidity 0.82 of blade (1), blade root cascade solidity is 1.4 times of blade tip cascade solidity, and blade tip aerofoil profile laying angle is 15.32 °.

2. a kind of Novel axial flow type impeller according to claim 1, is characterized in that: the quantity of described blade (1) is 4.