scholarly journals Effect of Blade Thickness on Internal Flow and Performance of a Plastic Centrifugal Pump

Machines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 61
Author(s):  
Zhenfa Xu ◽  
Fanyu Kong ◽  
Lingfeng Tang ◽  
Mingwei Liu ◽  
Jiaqiong Wang ◽  
...  

Blade thickness is an essential parameter of the impeller, which has significant effects on the pump performance. The plastic pump generally adopts thick blade due to low strength of plastic. The effects of blade thickness on the internal flow and performance of a plastic centrifugal pump were discussed based on the numerical methods. Two kinds of blade profile, the constant thickness blade (CTB) and the variable thickness blade (VTB), were investigated. The results indicated that, for the CTB, when the blade thickness was less than 6 mm, the pump performance did not change significantly. When the blade thickness exceeded 6 mm, the pump head and efficiency decreased rapidly. The pump head and efficiency of CTB 10 decreased by 42.2% and 30% compared with CTB 4, respectively. For the VTB, with blade thickness in a certain range (6 mm–14 mm), the pump performance changed slightly with the increased of trailing edge thickness. The minimum blade thickness of the plastic centrifugal pump should be 4 mm based on the finite element analysis. A variable thickness blade (VTB 4-8-4) with the maximum thickness located at 60% chord length was proposed to improve the pump performance, and its efficiency was 1.67% higher than that of the CTB 4 impeller.

Water ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 99
Author(s):  
Puyu Cao ◽  
Rui Zhu

Parallel compressor theory (PCT) is commonly used to estimate effects of inlet distortion on compressor performance. As well as compressor, the actual inflow to pump is also nonuniform and unfavorable for performances. Nowadays, insufficient understanding of nonuniform inflow effects on pump performance restricts its development. Therefore, this paper applies PCT to predict external characteristics and evaluate internal flow instability of waterjet pump under nonuniform inflow. According to features of nonuniform inflow, the traditional PCT is modified and makes waterjet pump sub-divided into two circumferential tubes owning same performances but with different inlet velocity (representing nonuniform inflow). Above all, numerical simulation has been conducted to validated the applicability and accuracy of PCT in head prediction of waterjet pump under nonuniform inflow, since area-weighted sum of each tube head (i.e., theoretical pump head) is highly consistent with simulated result. Moreover, based on identifications of when and which tube occurs stall, PCT evaluates four stall behaviors of waterjet pump: partial deep stall, partial stall, pre-stall and full stall. Furthermore, different stall behavior generates different interactions between head variation of each tube, resulting in a multi-segment head curve under nonuniform inflow. The modified PCT with associated physical interpretations are expected to provide a sufficient understanding of nonuniform inflow effects on pump performances.


2015 ◽  
Vol 809-810 ◽  
pp. 859-864
Author(s):  
Dănuţ Zahariea

In this paper, the finite element analysis for stress/deformation/modes of vibration for the centrifugal fan impeller with constant thickness backward-curved blades using CATIA software will be presented. The principal steps of the finite element analysis procedure using CATIA/Generative Structural Analysis environment will be presented: creating the 3D model; configuring the mesh; applying the restraints; applying the loads; running the numerical static analysis and the numerical frequency analysis; interpreting the results and observing the modes of vibration correlating with the impeller mode shape. This procedure will be used for 4 different centrifugal fan impellers according with the 4 blade design methods and the results will be comparatively analyzed. For each design method, two materials will be used: steel with density of 7860 kg/m3 and aluminium with density of 2710 kg/m3. Two important results have been obtained after the structural analysis: under the working conditions considered for the analysis, all 4 blade design methods leads to impellers with very good mechanical behaviour; any frequency of the main modes of vibrations for all blade design methods and for both materials is not in phase with the impeller speed, thus the possibility of resonance being eliminated.


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


2003 ◽  
Author(s):  
Satoshi Ogata ◽  
Keizo Watanabe ◽  
Asano Kimura

Performance of a centrifugal pump when handling surfactant solutions was measured experimentally. The effects of the concentration and temperature of surfactant solutions on pump performance were investigated. It was clarified that the pump efficiency with surfactant solutions was higher than that with tap water, and increased with an increase of surfactant concentration. The value of maximum flow rate of the pump also increased. The total pump head increased with an increase in the surfactant concentration, however, the shaft power decreased with a decrease in the rotational speed of the impeller. The pump efficiency is dependent on the surfactant temperature, and there is an optimal temperature which maximizes the efficiency.


2012 ◽  
Vol 229-231 ◽  
pp. 2454-2458
Author(s):  
Jian Jun Gan ◽  
Jie Gang Mou ◽  
Shui Hua Zheng ◽  
Bo Zhu

Based on CFD simulations and experimental research, this paper studied the mach of impeller outlet and diffuser inlet in stamping and welding centrifugal pump. The influence of area ratio Y of impeller outlet to diffuser inlet on pump internal flow characteristics and performance was studied. Five different area ratio pump models were analyzed. The results indicate that as the area ratio Y= F3/F2 increase, the velocity of fluid in diffuser inlet decreases continuously, the average static pressure of diffuser outlet increases, and the head and efficiency of the pump are risen. When the area ratio increases from Y=1.48 to Y=3.49, the head increases about 3.0% and the efficiency about 2.0%.


2021 ◽  
Author(s):  
Ning Zhang ◽  
Junxian Jiang ◽  
Xiaokai Liu ◽  
Bo Gao

Abstract High pressure pulsations excited by rotor stator interaction is always focused in pumps, especially for its control considering the stable operation. In the current research, a special staggered impeller is proposed to reduce intense pressure pulsations of a centrifugal pump with ns=69 based on alleviating rotor stator interaction. The numerical simulation method is conducted to illustrate the influence of staggered impeller on the pump performance and pressure pulsations, and three typical flow rates (0.8ФN-1.2ФN) are simulated. Results show that the staggered impeller will lead to the pump head increasing, and at the design working condition, the increment reaches about 3% compared with the original impeller. Meanwhile, the pump efficiency is little affected by the staggered impeller, which is almost identical with the original impeller. From comparison of pressure spectra at twenty monitoring points around the impeller outlet, it is validated that the staggered impeller contributes significantly to decreasing pressure pulsations at the concerned working conditions. At the blade passing frequency, the averaged reduction of twenty points reaches 89% by using the staggered impeller at 1.0ФN. The reduction reaches to 90%, 80% at 0.8ФN, 1.2ФN respectively. Caused by the rib within the staggered impeller, the internal flow field in the blade channel will be affected. Finally, it is concluded that the proposed staggered impeller surely has a significant effect on alleviating intense pressure pulsation of the model pump, which is very promising during the low noise pump design considering its feasibility for manufacturing.


Author(s):  
Zhengjing Shen ◽  
Wuli Chu

Sediment erosion is recognized as a serious engineering problem in slurry handling such as screw centrifugal pump, which has wide efficiency region and non-plugging performance. In the present study, the screw centrifugal pump was simulated based on the Euler-Lagrange method. The Mclaury model was adopted for the erosion prediction of flow passage components. By analyzing the correlation factor functions contained in the erosion model and performing some preliminary research with a simplified model, particle velocity, particle shape factor and particle concentration were selected as the influencing factors to analysis the quantitative relationship among particle parameters, erosion wear and performance of screw centrifugal pump. The results show that the erosion of volute casing is higher than impeller, and the erosion rate of suction side is higher than pressure side. The particles velocity is positively correlated with erosion wear and pump performance reduction rate. While the increase of particles shape factor shows the opposite trend. Erosion rate is found to be increases sharply and then slowly when particles concentration increases, because of the adhesion effect of sand particles in the volute casing inhibits the total erosion wear. The increase of erosion rate promoted the reduction rate of pump performance, and the pump efficiency decreased more significantly when the erosion rate increased to a certain extent. The results of this study are of great significance for further optimization of hydraulic design and structural design for screw centrifugal pump.


2011 ◽  
Vol 80-81 ◽  
pp. 927-931 ◽  
Author(s):  
Yan Qing Wang ◽  
Gao Yan Zhong ◽  
Yong Biao Chang ◽  
Guo Xin Liu

The stroke and the material characteristics of the large five-axis machining center were expounded; a structure similar to the truss of the reinforced beam plates was designed according to the design requirements of the beam structure, this structure could make the frame gain high rigidity in small size, the frame made by the rods could be constituted with high rigidity, the overall rigidity of the machining center could be improved 23% - 25%; three different beam structures were designed, and the finite element analysis software ANSYS was carried out to analyze their static characteristics, the maximum deformations in three directions X, Y, Z were obtained; compared with other structures through the comparisons on mass, stiffness and performance, the optimal structure was obtained, its mass was 1818Kg, and its maximum deformations in X, Y, Z directions were 0.45mm, 0.07mm and 0.13mm, respectively.


2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Hui Zhang ◽  
Lingfeng Tang ◽  
Yongtao Zhao

To study the influence of blade profiles of the plastic centrifugal pump on pump performance, the impeller blade profiles were designed and drawn by the single arc method, double arc method, logarithmic spiral method, and B-spline curve method, respectively, with the known structural parameters.The shape and size of four profiles were drawn, and two-dimensional models and three-dimensional models of four impellers and volute were completed, respectively. The impeller models were printed by 3D printing technology, and the performance experiments of the plastic centrifugal pump were carried out. The numerical simulation of the internal flow field was performed. From the contours of the velocity and pressure, the vapor volume fraction distribution, and fluid-structure interaction analysis of impellers, the impeller drawn by the logarithmic spiral method was better than others. The optimization of the logarithmic spiral method was completed. The impeller inlet and outlet diameters (D1 and D2) and impeller inlet and outlet installation angles (β1 and β2) were taken as control variables, and the total power loss and the minimum NPSHr of the pump were taken as the objective functions. The optimization results were that D1 = 58 mm and D2 = 162 mm and β1 = 17° and β2 = 31°. The hydraulic efficiency was increased by 1.68%.


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