Axial flow pump impeller all-operating-condition design method

Abstract

An axial flow pump impeller all-operating-condition design method comprises the following steps that 1, parametric modeling of an axial flow pump impeller is performed, namely 2k design parameters including k wing section cascade solidities and wing placement angle values of the axial flow pump impeller are selected; 2, all-operating-condition optimal design is performed: firstly, conventional design parameters of the impeller are dertemined, then numerical calculation is conducted on the design conditions of the axial flow pump impeller and various losses in a pump are comprehensively analyzed to preliminarily design the axial flow pump impeller having better hydraulic performance under the design conditions in a total-loss minimization mode; secondly, guide blades, a water guide cone and water inlet and outlet flowing channels of the impeller are designed; thirdly, the optimal all-operating-condition weighted average effciency of the pump device is regarded as a target, a lift is regarded as a constraint condition, and a seqential quadratic programming method of a gradient optimum algorithm is adopted to constantly change the design parameters of the axial flow pump impeller and perform iterative numerical calculation of the pump device. The axial flow pump impeller all-operating-condition design method adopts CFD numerical calculation, the design accuray is high, and optimization results are reliable.

Description

technical field [0001] The invention relates to a method for designing the impeller of an axial flow pump under all working conditions, and belongs to the technical field of water conservancy and power engineering. Background technique [0002] The traditional axial flow pump design method is a single design method only according to the design working conditions, that is, a certain set of design flow and design head values ​​are put forward according to the application occasions, and the design of the whole pump is carried out, but the so-called design working conditions are actually only the head. - A point on the flow (H-Q) performance curve. The design using the traditional design method only guarantees the performance of the design point under ideal fluid and idealized flow conditions. As for the performance under non-design conditions, it cannot be guaranteed in the design, or can only be obtained from experiments. . In most cases, the site where the axial flow pump i...

AI Technical Summary

Problems solved by technology

However, the traditional axial flow pump design method one-sidedly pursues higher efficiency requirements under design conditions, ignoring other hydraulic performance requirements

Therefore, the traditional design method of this design condition will be increasingly unable to meet the increasingly complex production requirements. The defects of the traditional design method of the axial flow pump impeller mainly include the following aspects:

[0003] 1. The theory of the method is the Euler equation, and the Euler equation only establishes the relationship between the external characteristic parameters and the speed of the impeller inlet and outlet of the axial flow pump, and does not analyze the flow field and pressure field inside the impeller, although some designs consider the liquid Viscous effects, corrected by empirical formula, but still too rough

[0004] 2. The design process is aimed at the impeller of the axial flow pump itself, without considering the influence of the guide vane, inlet and outlet water passages and other flow components on the internal flow of the axial flow pump and the performance of the axial flow pump

[0005] 3. The design process is oversimplified, with large human factors and large errors

[0006] 4. The performance of the axial flow pump under non-design conditions cannot be balanced, and the efficiency under design conditions can only reach the level of the statistical data, and it is difficult to further improve

[0007] 5. The design is carried out sequentially, without considering the interaction between upstream and downstream and various losses

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