scholarly journals Liquid/solid flow field in a centrifugal pump with different impeller blade types by PIV

2021 ◽  
pp. 002029402110223
Author(s):  
Baocheng Shi ◽  
Kun Xue ◽  
Jianpeng Pan ◽  
XingKai Zhang ◽  
Ruomeng Ying ◽  
...  

In this study, a non-stirred Particle Image Velocimetry (PIV) testing device is developed to measure the flow field in a solid–liquid two-phase centrifugal pump. The pump casing and impeller are made of an organic glass material. Two types of impellers are designed considering different structure parameters. The performance curves of the pump are obtained for the different impellers at a rotating speed of 900 rpm with particle concentrations of 0%, 3%, 5%, and 10%. The flow fields for water and a solid–liquid two-phase mixture for the two impellers are measured utilizing the PIV system in a centrifugal rotating frame at the designed condition. The distribution of the particles, together with its influence on the performance of the different impellers, is analyzed. From a comparison of the relative velocity vector fields, the following can be concluded. First, the pump with a double arc-shaped profile demonstrated a more uniform and stable flow field distribution and higher performance than that with a single arc profile. Secondly, the solid particles were distributed mainly at the outlet of the impeller and volute wall, whereas the concentration distribution of the larger particles tended to match the pressure surface. This research can provide theoretical guidance for the design and optimization of two-phase flow centrifugal pumps.

2021 ◽  
Vol 37 ◽  
pp. 192-204
Author(s):  
Baocheng Shi ◽  
Kaili Zhou ◽  
Jianpeng Pan ◽  
XingKai Zhang ◽  
Ruomeng Ying ◽  
...  

Abstract Flow fields for various impellers were measured using water and a two-phase liquid–solid mixture with a particle image velocimetry system in a centrifugal rotating frame in controlled conditions. After measuring absolute velocity vectors in impeller passages, the vectors were decomposed based on the triangle speed principle and the distribution of relative velocity vectors within the impeller was obtained. Then, the distribution of particles and their influence on the performance of different impellers were analyzed. The following conclusions were made from the comparison of relative velocity vector field: first, the wear on the outlet of blades can be mitigated effectively by reducing the outlet angle of impeller blades; second, the pump with a double-arc-shaped profile had a more uniform and stable flow field distribution and higher performance than that with a single-arc profile; and finally, the “jet–wake” structure can be improved significantly by using impellers with long and short blades, resulting in a remarkable reduction in energy loss and improvement in pump efficiency. We also found that solid particles were mainly distributed at the outlet of the impeller and volute wall, while the concentration distribution of large particles tended to match the pressure surface. This research can provide some theoretical guidance for the design and optimization of two-phase flow centrifugal pumps.


Symmetry ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2003
Author(s):  
Chaoshou Yan ◽  
Jianfei Liu ◽  
Shuihua Zheng ◽  
Bin Huang ◽  
Jiacheng Dai

In order to study the wear law of the centrifugal pump flowing surface under different wear-rings clearance, the McLaury wear model was used to conduct the full-passage numerical simulation of solid-liquid two-phase flow in a single-stage single-suction centrifugal pump. The reliability of the numerical calculation method is verified by comparing the experimental data and numerical simulation results. The clearance is 0.1, 0.15, 0.2, 0.3 and 0.5 mm, respectively. The results show that the wear of the centrifugal pump blades is mainly concentrated in the end part and the inlet part of the blade, and the wear of the pressure surface at the end of the suction surface and the front of the blade is more serious. As the clearance increases, the maximum wear value in the impeller increases first and then decreases, reaching a maximum at 0.15 mm. With the increase of the clearance, the wear degree and the wear rate of the volute wall surface first increase and then decrease, and reach the maximum at 0.2 mm. With the increase of the clearance and the concentration of the fluid medium, the wear at the clearance of the centrifugal pump is more serious, and the severe wear area exhibits a point-like circumferential distribution.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Yanping Wang ◽  
Bozhou Chen ◽  
Ye Zhou ◽  
Jianfeng Ma ◽  
Xinglin Zhang ◽  
...  

To study the effect of fine particle size and volume concentration on the performance of solid-liquid two-phase centrifugal pump, the mixture multiphase flow model, RNG k-ε turbulence model, and SIMPLEC algorithm were used to simulate the two-phase flow of the centrifugal pump. The effects of particle size and volume concentration on internal pressure distribution, solid volume distribution, and external characteristics were analyzed. The results show that under the design discharge conditions, with the increase of particle size and volume concentration, the internal pressure of the flow field will decrease, and the volume fraction of solid phase in the impeller passage will also decrease as a whole. The solid particles gradually migrate from the suction surface to the pressure surface, and the particles in the volute channel are mainly concentrated in the flow channel near the outlet side of the volute. With the increase of particle size and volume concentration, the negative pressure value at the inlet of centrifugal pump increases, the total pressure difference at the inlet and outlet decreases, and the head and efficiency decrease accordingly.


Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1483
Author(s):  
Xijie Song ◽  
Dunzhe Qi ◽  
Lijuan Xu ◽  
Yubin Shen ◽  
Wei Wang ◽  
...  

The double-suction centrifugal pumps installed along the Yellow River in China face serious sediment erosion due to the high sediment content which causes the poor operation efficiency of the pump units. The particle motion characteristics and erosion characteristics in a pump under different flow rates and different particle concentrations were numerically simulated based on the particle track model of solid-liquid two-phase flow. The results show that the flow rate has a significant effect on the particle tracks and the erosion caused by the particles in the impeller. The total erosion rate is positively correlated with the flow rate, and increases with the increase in flow rate. The vortex and secondary flow in the impeller have obvious influence on the particle trajectory, which increases the particle concentration at the trailing edge of the pressure surface and intensifies the impact erosion in this area. The particles carried by the vortex intensifies the local erosion. The particle concentration mainly affects the erosion rate, but has little effect on the erosion position. The influence of flow rate on pump erosion is greater than that of the particle properties. These results provide a reference for optimization of the design of anti-erosion blades of double-suction pumps and the regulation and operation of pumping stations.


Author(s):  
Fen Lai ◽  
Xiangyuan Zhu ◽  
Xun Xu ◽  
Guojun Li

Erosion wear caused by solid particles is recognized as one of the major concerns for centrifugal pumps. In this paper, a two-way coupled Eulerian-Lagrangian approach is employed to solve the solid-liquid flow in the centrifugal pump. The erosion model developed in the Erosion/Corrosion Research Center (E/CRC), combined with the Grant and Tabakoff particle-wall rebound model, are employed to predict particles behaviors and erosion wear. Three-dimensional transient calculation of the centrifugal pump for solid-liquid flow is carried out to research the performance and erosion wear of centrifugal pump. The influence of concentrations and diameters of solid particles are also investigated. The results show that the existence of solid particles decreases the static pressure and the velocity of liquid. The frequency of impingement and rebound will increase with the increase of the concentrations of solid particles. The middle of the hub and the trailing edge of blades pressure side are the most serious erosion regions.


Processes ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1317
Author(s):  
Biaobiao Wang ◽  
Haoyang Zhang ◽  
Fanjie Deng ◽  
Chenguang Wang ◽  
Qiaorui Si

In order to study the internal flow characteristics of centrifugal pumps with a split impeller under gas-liquid mixed transportation conditions, this paper conducted a steady calculation of the flow field in the centrifugal pump under the conditions of different inlet gas volume fractions based on the Eulerian-Eulerian heterogeneous flow model, using air and water as the working media and the Schiller Nauman model for the interphase resistance. This paper takes a low specific speed centrifugal pump as the research object, through the controlling variables, using the same pump body structure and pump body geometric parameters and setting three different arrangements of long and short blades (each plan uses the same long and short blades) to explore the influence of the short blade arrangement on the low specific speed centrifugal pump performance under a gas-liquid two-phase flow. The research results show that, under pure water conditions, the reasonable arrangement of the short blade circumferential position can eliminate the hump of the centrifugal pump under low-flow conditions, can make the flow velocity in the impeller more uniform, and can optimize the performance of the pump. Under the design conditions and the gas-liquid two-phase inflow conditions, when the circumferential position of the short blades is close to the suction surface of the long blades, some of the bubbles on the suction surface of the long blade can be broken under the work of the pressure surface of the short blade and flow out of the impeller with the liquid, which improves the flow state of the flow field in the impeller.


2019 ◽  
Vol 23 (1) ◽  
pp. 259-270 ◽  
Author(s):  
Reza Barmaki ◽  
Mir Biyouk Ehghaghi

Abstract In petroleum and mine industries, the centrifugal pumps were used for transferring solid particles with water. This method is preferable to other methods because of its user friendly and economic issues. In this article by selecting a proper pump and designing test circuit, we conducted hydraulic tests for water and water mixture with solid particles. For this purpose, an experimental set-up of centrifugal pump with only water and water with solid particles was developed. Then by analyzing the test results and efficiency equation, optimal coefficients of head loss is provided to improve the pump efficiency during hydraulic transmission of solids. The experimental results of power consumption, head, and pressure difference measurements in solid–liquid systems are presented. The experimental set-up results are compared with simulation and numerical one, which show a good agreement with them. It reveals that by adding the solid particles and increasing the fluid density up to 15%, the consumed power increases by about 20%, which result in dropping the efficiency of hydraulic system up to 6%. Finally, the optimal components for developed cycle presented for evaluation the various configuration and hydraulic analysis of pure flow and flow with solid particles in various applications to enhance the most achievable efficiency.


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.


Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 886
Author(s):  
Cui Dai ◽  
Chao Guo ◽  
Yiping Chen ◽  
Liang Dong ◽  
Houlin Liu

The strong noise generated during the operation of the centrifugal pump harms the pump group and people. In order to decrease the noise of the centrifugal pump, a specific speed of 117.3 of the centrifugal pump is chosen as a research object. The bionic modification of centrifugal pump blades is carried out to explore the influence of different bionic structures on the noise reduction performance of centrifugal pumps. The internal flow field and internal sound field of bionic blades are studied by numerical calculation and test methods. The test is carried out on a closed pump test platform which includes external characteristics and a flow noise test system. The effects of two different bionic structures on the external characteristics, acoustic amplitude–frequency characteristics and flow field structure of a centrifugal pump, are analyzed. The results show that the pit structure has little influence on the external characteristic parameters, while the sawtooth structure has a relatively great influence. The noise reduction effect of the pit structure is aimed at the wide-band noise, while the sawtooth structure is aimed at the discrete noise of the blade-passing frequency (BPF) and its frequency doubling. The noise reduction ability of the sawtooth structure is not suitable for high-frequency bands.


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