Internal flow numerical simulation of double-suction centrifugal pump using DES model

2012 ◽  
Vol 15 (3) ◽  
pp. 032051 ◽  
Author(s):  
P J Zhou ◽  
F J Wang ◽  
M Yang
2021 ◽  
Vol 9 (2) ◽  
pp. 121
Author(s):  
Yang Yang ◽  
Ling Zhou ◽  
Hongtao Zhou ◽  
Wanning Lv ◽  
Jian Wang ◽  
...  

Marine centrifugal pumps are mostly used on board ship, for transferring liquid from one point to another. Based on the combination of orthogonal testing and numerical simulation, this paper optimizes the structure of a drainage trough for a typical low-specific speed centrifugal pump, determines the priority of the various geometric factors of the drainage trough on the pump performance, and obtains the optimal impeller drainage trough scheme. The influence of drainage tank structure on the internal flow of a low-specific speed centrifugal pump is also analyzed. First, based on the experimental validation of the initial model, it is determined that the numerical simulation method used in this paper is highly accurate in predicting the performance of low-specific speed centrifugal pumps. Secondly, based on the three factors and four levels of the impeller drainage trough in the orthogonal test, the orthogonal test plan is determined and the orthogonal test results are analyzed. This work found that slit diameter and slit width have a large impact on the performance of low-specific speed centrifugal pumps, while long and short vane lap lengths have less impact. Finally, we compared the internal flow distribution between the initial model and the optimized model, and found that the slit structure could effectively reduce the pressure difference between the suction side and the pressure side of the blade. By weakening the large-scale vortex in the flow path and reducing the hydraulic losses, the drainage trough impellers obtained based on orthogonal tests can significantly improve the hydraulic efficiency of low-specific speed centrifugal pumps.


2015 ◽  
Vol 32 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Xiao-Qi Jia ◽  
Bao-Ling Cui ◽  
Yu-Liang Zhang ◽  
Zu-Chao Zhu

AbstractTo study the influence of tip clearance on internal flow characteristics and external performance of a prototype centrifugal pump with a semi-open impeller, the unsteady numerical simulation and performance experiments are carried out in this paper. The evolution process of leakage vortex with time


2013 ◽  
Vol 694-697 ◽  
pp. 56-60
Author(s):  
Yue Jun Ma ◽  
Ji Tao Zhao ◽  
Yu Min Yang

In the paper, on the basis of three-dimensional Reynolds-averaged Navier-Stokes equations and the RNG κ-ε turbulence model, adopting Three-dimensional unstructured grid and pressure connection the implicit correction SIMPLEC algorithm, and using MRF model which is supported by Fluent, this paper carries out numerical simulation of the internal flow of the centrifugal pump in different operation points. According to the results of numerical simulation, this paper analyzes the bad flow phenomena of the centrifugal pump, and puts forward suggests about configuration perfected of the centrifugal pump. In addition, this paper is also predicted the experimental value of the centrifugal pump performance, which is corresponding well with the measured value.


2011 ◽  
Vol 55-57 ◽  
pp. 582-586
Author(s):  
Shu Jia Zhang ◽  
Yue Ping Tong ◽  
Le Hu

In order to examine applicability of the Reynolds-Averaged Navier-Stokes (RANS)using Reynolds Stress equation Model (RSM) and the Large Eddy Simulation (LES) in numerical simulation of centrifugal pump, a series of 3D numerical simulation at the design point and at six off-design points were carried out with the two methods. The object is based on IS80-65-160 centrifugal pump. According to the results obtained, head, shaft power, efficiency of pump were calculated, the simulated performance curves of a centrifugal pump is processed. The simulated performance curves of a centrifugal pump were compared with the experimental performance curves. It was confirmed that RANS were suitable for the numerical simulation of the internal flow inside a centrifugal pump. But the result of LES is not very good if the same gambit which is suitable for RANS was used. Therefore, the computer resources, not propose the Large Eddy Simulation (LES) method in numerical simulations of centrifugal pump.


Author(s):  
A. Farid Ayad ◽  
H. M. Abdalla ◽  
A. Abou El-Azm

Centrifugal pumps (CP) are probably among the most often used machinery in industrial facilities as well as in common practice. Compared to other types of rotating pumps, CP yield higher efficiency. In aerospace application reducing the weight of the CP impeller has the advantage of reducing mechanical stresses and enable using the CP at high number of revolution. In order to minimize the impeller weight the requirements to study and develop the CP with semi-open impeller appears. Using this type of impeller results in clearance between the impeller blades and the casing which degrade the centrifugal pump performance. The impact of this side clearance has not been deeply investigated in open literature. The present paper is devoted to reveal more details about the impact of CP side clearance on its performance. This is done by numerically investigating the influence of the variation of the CP side clearance width (0:0.2 impeller width) on the CP performance parameters at different flow rates (0:5 Liter/s). These CP performance parameters include the pump head, efficiency, slip factor, blades loads and the internal flow structure. 3-D steady numerical simulation has been carried out using commercial software, ANSYS® CFX. The computational domain consists of four zones: inlet, side gab, impeller and volute with outlet. They are defined by means of the multi-reference frame technique. The impeller is situated in the rotating reference frame, while the inlet, side gab and outlet zones are in the fixed reference frame, and they are related to each other through the “frozen rotor” interface. The meshes of four computational domains are generated separately after performing mesh sensitivity analysis. The boundary conditions are set as total pressure at inlet and the mass flow at outlet. A no-slip condition is imposed at the wall boundary defined at the blade and casing. A turbulent, incompressible flow solver has been adapted using SST k–ω turbulent model. The numerical simulation has been compared with own experimental results and a published empirical formulas to verify the numerical solution. The CFD results show an acceptable agreement with the results of the experimental work and the empirical formulas. It has been shown that the impeller side clearance have a great regression effect on the centrifugal pump performance. An explanation to the performance regression has been proposed based on the flow field feature. Performance regression could be attributed to the drop in the pressure difference between the impeller inlet and outlet. And the redistribution of the velocity inside the impeller channel and the side clearance.


2013 ◽  
Vol 444-445 ◽  
pp. 1007-1014 ◽  
Author(s):  
Hui Quan ◽  
Ren Nian Li ◽  
Qing Miao Su ◽  
Wei Han ◽  
Xiao Rui Cheng

To explore the screw centrifugal pump performance change, and the impact of solid-liquid two-phase flow on the screw centrifugal pump, the internal flow of type 150×100LN-32 centrifugal pump is used as the research object. Mixture multiphase flow model, standard k-ε turbulence model and the sliding mesh technique are used to carry out the unsteady numerical simulation to describe internal flow field in screw centrifugal pump. By Setting the monitoring point to get the pressure pulsation characteristics and predict the changes in the energy performance. Open laboratory bench tests are carried out to verify the reliability of the numerical methods. Based on this, the impact of the two-phase flow on the screw centrifugal pump is analyzed. The results indicate that the head-flow curve presents a hump-shaped with the increasing of the flow. The maximum of efficiency appears. At the same time, the change of the volume concentration of the solid phase has little effect on the energy performance of screw centrifugal pump. But at different times, the head decreases and the power increases with the increasing of the concentration.


2021 ◽  
Vol 13 (9) ◽  
pp. 168781402110499
Author(s):  
Xianfang Wu ◽  
Xuelei Sun ◽  
Minggao Tan ◽  
Houlin Liu

The operating characteristics of a centrifugal pump with broken impeller malfunction was studied by tests and numerical simulation. One blade was cut 1/4 as a broken impeller. The energy characteristics, vibration, internal flow, pressure fluctuation, and radial force of the pump were studied in detail. The test results show that as for the pump with broken impeller, the head decreased by 9.85% and efficiency decreased by 1.06% under 1.0 Q0. The vibration increase amplitudes at the outlet flange are the maximum. The APF (axial passing frequency) of all monitoring points increased significantly, and a new frequency – 5APF appeared, except for the inlet of the pump. It can be found that the low-speed region of blade fracture surface is more obvious than other blades through numerical simulation. The radial force of the broken impeller increased obviously and became more concentrated. Due to the broken blade, the peak-to-peak magnitude of pressure fluctuation at the tongue and pump outlet increased by 4.7% and 9.5% respectively. The research results provide some reference for the malfunction diagnosis of centrifugal pump.


Author(s):  
Weihui Xu ◽  
Xiaoke He ◽  
Xiao Hou ◽  
Zhihao Huang ◽  
Weishu Wang

AbstractCavitation is a phenomenon that occurs easily during rotation of fluid machinery and can decrease the performance of a pump, thereby resulting in damage to flow passage components. To study the influence of wall roughness on the cavitation performance of a centrifugal pump, a three-dimensional model of internal flow field of a centrifugal pump was constructed and a numerical simulation of cavitation in the flow field was conducted with ANSYS CFX software based on the Reynolds normalization group k-epsilon turbulence model and Zwart cavitation model. The cavitation can be further divided into four stages: cavitation inception, cavitation development, critical cavitation, and fracture cavitation. Influencing laws of wall roughness of the blade surface on the cavitation performance of a centrifugal pump were analyzed. Research results demonstrate that in the design process of centrifugal pumps, decreasing the wall roughness appropriately during the cavitation development and critical cavitation is important to effectively improve the cavitation performance of pumps. Moreover, a number of nucleation sites on the blade surface increase with the increase in wall roughness, thereby expanding the low-pressure area of the blade. Research conclusions can provide theoretical references to improve cavitation performance and optimize the structural design of the pump.


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