Multi-objective Optimization by Using Modified PSO Algorithm for Axial Flow Pump Impeller

Author(s):  
H. S. Park ◽  
Fu-qing Miao
Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3053
Author(s):  
Youn-Sung Kim ◽  
Man-Woong Heo ◽  
Hyeon-Seok Shim ◽  
Bong-Soo Lee ◽  
Dong-Hwan Kim ◽  
...  

Submersible pumps are now in high demand due to the sporadic occurrence of recent torrential rains. The current study was carried out to investigate the hydraulic characteristics of a submersible axial-flow pump with a swept impeller and to optimize the impeller and diffuser shapes of the pump to enhance the hydraulic performance. Three-dimensional Reynolds-averaged Navier–Stokes equations were solved with the shear stress transport turbulence model. The governing equations were discretized using the finite volume method, and unstructured tetrahedral and hexahedral meshes were used in the grid system. The optimal grid system was selected through a grid dependency test. A performance test for the submersible axial-flow pump was carried out experimentally, and the results of the numerical analysis were validated against the experimental results. The hydraulic efficiency and the total head were used as objective functions. For the first optimization, a multi-objective optimization was carried out to simultaneously improve the objective functions through a hybrid multi-objective evolutionary algorithm coupled with a response surface approximation by varying the swept angle and pitch angle of the blades of the rotating impeller. The second multi-objective optimization was performed using two design variables, i.e., the inlet angle and the length of the diffuser vanes, to simultaneously increase the objective functions. Clustered optimum designs in the Pareto optimal solutions yielded significant increases in the objective function values as compared with the reference design.


Water ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1493
Author(s):  
Weidong Cao ◽  
Wei Li

The operating range of axial flow pumps is often constrained by the onset of rotating stall. An improved method using a double inlet nozzle to stabilize the performance curve is presented in the current study; a single inlet nozzle and three kinds of double inlet nozzle with different rib gap widths at the inlet of axial flow pump impeller were designed. Three dimensional (3D) incompressible flow fields were simulated, and the distributions of turbulence kinetic energy and velocity at different flow rates located at the inlet section, as well as the pressure and streamline in the impeller, were obtained at the same time. The single inlet nozzle scheme and a double inlet nozzle scheme were studied; the experimental and numerical performance results show that although the cross section is partly blocked in the double inlet nozzle, the head and efficiency do not decline at stable operation flow rate. On small flow rate condition, the double inlet nozzle scheme effectively stabilized the head-flow performance, whereby the block induced by the backflow before the impeller was markedly improved by using a double inlet nozzle. It has also been found that the rib gap width impacts the efficiency curve of the axial flow pump.


1983 ◽  
Vol 105 (3) ◽  
pp. 277-283 ◽  
Author(s):  
M. Murakami ◽  
K. Minemura

Motion of air bubbles in a high-specific-speed axial-flow pump impeller was analyzed on the basis of measured streak lines of air bubbles in the impeller. The results were compared with those obtained by a numerical solution of the bubble motion equations for three dimensional flow. Governing factors of the bubble motion are the drag force due to the surrounding water and the force due to the pressure gradient. Trajectories of the bubbles deviate somewhat from the streamlines of water, and the amount of the deviation is dependent on the bubble diameter and also on specific-speeds of the pumps and flow rate of water.


2015 ◽  
Vol 741 ◽  
pp. 481-485
Author(s):  
Hong Ming Zhang ◽  
Li Xiang Zhang

The paper presents numerical simulation of the vortex in a submersible axial flow pump impeller using OpenFoam code. A mixture assumption and a finite rate mass transfer model were introduced to analyze vortex. The finite volume method is used to solve the governing equations of the mixture model and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators (PISO) procedure. Simulation results have shown that the cavitation may occur on the lower portion of impeller suction side. And the blade channel vortex will be formed in the impeller. It can induce the pressure pulsation in the impeller and can result in reduced efficiency of the submersible axial flow pump.


2008 ◽  
Vol 130 (7) ◽  
Author(s):  
Wen-Guang Li

The two-step method for optimizing net positive suction head required (NPSHr) of axial-flow pumps is proposed in this paper. First, the NPSHr at the impeller tip is optimized with impeller diameter based on experimental data of 2D cascades in available wind tunnels. Then, it is optimized again with the velocity moment at the impeller outlet, which is expressed in terms of two parameters. The blade geometry is generated and flow details are clarified by using the radial equilibrium equation, actuator disk theory, and 2D vortex element method in the optimizing process. The NPSHr response surface has been established in terms of these two parameters. The results illustrate that the second optimization allows NPSHr to be reduced by 37.5% compared to the first optimization. Therefore, this two-step method is effective and expects to be applied in the axial-flow pump impeller blade design. The simulations of 3D turbulent flow with various cavitation models and related confirming experiments are going to be done in the axial-flow impellers designed with this method.


Sign in / Sign up

Export Citation Format

Share Document