Energy Performance Prediction and Numerical Simulation Analysis for Screw Centrifugal Pump

2013 ◽  
Vol 444-445 ◽  
pp. 1007-1014 ◽  
Author(s):  
Hui Quan ◽  
Ren Nian Li ◽  
Qing Miao Su ◽  
Wei Han ◽  
Xiao Rui Cheng
Keyword(s):  
Numerical Simulation ◽  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Solid Phase ◽  
Internal Flow ◽  
Energy Performance ◽  
Phase Flow ◽  
Two Phase ◽  
Monitoring Point ◽  
The Impact

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.

Calculating Method for the Solid Phase Effect Coefficient of the Solid-Fluid Two Phase Flow Centrifugal Pump

2010 ◽  
Vol 29-32 ◽  
pp. 658-663
Author(s):  
Chuan Jun Li ◽  
Gang Yu ◽  
Xin Wang
Keyword(s):  
Differential Equation ◽  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Solid Phase ◽  
High Accuracy ◽  
Phase Flow ◽  
Phase Effect ◽  
Two Phase ◽  
Error Band ◽  
Calculating Method

In order to acquire the solid-fluid two phase flow centrifugal pump’s slurry head according with the fact, the solid phase effect coefficient must be calculated precisely. By analysising the acting forces on the solid particle, its moving differential equation was established. And the calculating formula of the solid phase effect coefficient was deduced based on the equation. For the sake of verifying its validity, a test of contrast and comparison on the calculating slurry heads by some ways was carried out. The results shows that the relative error values of the slurry head calculated are less than 2.00% with a small and stably error band. The method has the advantage of simple calculating process, high accuracy, low randomness and good practicability.

scholarly journals Wear Characteristics of Dense Fine Particles Solid-Liquid Two-Phase Fluid Centrifugal Pump with Open Impellers

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Yanping Wang ◽  
Chuanfeng Han ◽  
Ye Zhou ◽  
Zhe Lin ◽  
Jianfeng Ma ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Centrifugal Pump ◽  
Volume Concentration ◽  
Fine Particles ◽  
Two Phase Flow ◽  
Middle Part ◽  
Phase Flow ◽  
Particle Volume ◽  
Two Phase ◽  
Wear Characteristics

The demand for a centrifugal pump with open impellers for conveying dense fine particles in solid-liquid two-phase flow has increased significantly in actual engineering. The wear of dense fine particles on the centrifugal pump is also exceedingly prominent, which affects the engineering efficiency and economic benefits. The two-phase flow in the open centrifugal pump is three-dimensional and unsteady; the movement of high-volume concentration particles in the centrifugal pump and its mutual influence on the two-phase flow, which results in the calculation of wear, are very intricate. To study the wear characteristics of the centrifugal pump with open impeller with high-volume concentration particles more accurately, numerical simulation and experimental comparison are carried out for the impeller wear of dense fine particles transported by the centrifugal pump with open impellers. Considering the relationship between particles and walls, we used the Fluent 18.0 built-in rebound function and wear model. The RNG k-ε model and the DDPM model were adopted in the numerical simulation, and the numerical solution for centrifugal pump wear was performed under flow rate (9.6 m3·h−1, 12.8 m3·h−1, 16 m3·h−1, and 19.2 m3·h−1), different particle sizes (0.048 mm, 0.106 mm, 0.15 mm, 0.27 mm, and 0.425 mm), and different particle volume concentrations (10%, 15%, 20%, 25%, and 30%), respectively. By comparing the serious wear positions of the impeller, the experimental results correspond well with the numerical simulation, which can be used to predict and study the wear characteristics of the impeller. The results show that the most serious area of blade wear is the middle part of the pressure surface, followed by the middle part of the upper part of the blade. The wear of the impeller is greatly affected by relevant parameters, such as pump flow rate, particle diameter, and particle volume concentration. These results can provide some basis for the wear-resistant design of dense fine particle impeller.

scholarly journals Numerical Simulation of Gas–Liquid Two-Phase Flow Characteristics of Centrifugal Pump Based on the CFD–PBM

Mathematics ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 769 ◽  
Author(s):  
Fan Zhang ◽  
Lufeng Zhu ◽  
Ke Chen ◽  
Weicheng Yan ◽  
Desmond Appiah ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Average Diameter ◽  
Balance Model ◽  
Phase Flow ◽  
Centrifugal Pumps ◽  
Two Phase ◽  
Coalescence Rate ◽  
Breakage Rate

This work seeks to apply the computational fluid dynamics–population balance model (CFD–PBM) to investigate the gas distribution and flow mechanism in the gas–liquid two-phase flow of a centrifugal pump. The findings show that the numerical simulation accurately captures the bubble distribution characteristics in the process of coalescence and breakage evolution. In addition, comparing the CFD–PBM with the Double Euler, the hydraulic head of the pump are similar, but the efficiency using the Double Euler is much higher—even close to single-phase. This is in contrast to previous experimental research. Then, the unsteady flow usually led to the formation of bubbles with larger diameters especially where vortices existed. In addition, the rotor–stator interaction was a main reason for bubble formation. Generally, it was observed that the coalescence rate was greater than the breakage rate; thus, the coalescence rate decreased until it equaled the breakage rate. Thereafter, the average diameter of the bubble in each part tended to be stable during the process of bubble evolution. Finally, the average diameter of bubbles seemed to increase from inlet to outlet. The results of this study may not only enhance the gas–liquid two-phase internal flow theory of centrifugal pumps, but also can serve as a benchmark for optimizations of reliable operation of hydraulic pumps under gas–liquid two-phase flow conditions.

scholarly journals Study on the Effects of the Wear-Rings Clearance on the Solid-Liquid Two-Phase Flow Characteristics of Centrifugal Pumps

Symmetry ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2003
Author(s):  
Chaoshou Yan ◽  
Jianfei Liu ◽  
Shuihua Zheng ◽  
Bin Huang ◽  
Jiacheng Dai
Keyword(s):  
Numerical Simulation ◽  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Centrifugal Pumps ◽  
Suction Surface ◽  
Two Phase ◽  
Wear Area ◽  
Fluid Medium ◽  
Solid Liquid

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.

Numerical Simulation of Two-Phase Flow in Severely Damaged Core Geometries

2006 ◽  
Author(s):  
Phongsan Meekunnasombat ◽  
Florian Fichot ◽  
Michel Quintard
Keyword(s):  
Numerical Simulation ◽  
Porous Medium ◽  
Two Phase Flow ◽  
Immiscible Fluids ◽  
Macroscopic Model ◽  
Phase Flow ◽  
Two Phase ◽  
Fuel Rods ◽  
The Core ◽  
The Impact

In the event of a severe accident in a nuclear reactor, the oxidation, dissolution and collapse of fuel rods is likely to change dramatically the geometry of the core. A large part of the core would be damaged and would look like porous medium made of randomly distributed pellet fragments, broken claddings and relocated melts. Such a complex medium must be cooled in order to stop the accident progression. IRSN investigates the effectiveness of the water re-flooding mechanism in cooling this medium where complex two-phase flows are likely to exist. A macroscopic model for the prediction of the cooling sequence was developed for the ICARE/CATHARE code (IRSN mechanistic code for severe accidents). It still needs to be improved and assessed. It appears that a better understanding of the flow at the pore scale is necessary. As a result, a direct numerical simulation (DNS) code was developed to investigate the local features of a two-phase flow in complex geometries. In this paper, the Cahn-Hilliard model is used to simulate flows of two immiscible fluids in geometries representing a damaged core. These geometries are synthesized from experimental tomography images (PHEBUS-FP project) in order to study the effects of each degradation feature, such as displacement and fragmentation of the fuel rods and claddings, on the two-phase flow. For example, the presence of fragmented fuel claddings is likely to enhance the trapping of the residual phase (either steam or water) within the medium which leads to less flow fluctuations in the other phase. Such features are clearly shown by DNS calculations. From a series of calculations where the geometry of the porous medium is changed, conclusions are drawn for the impact of rods damage level on the characteristics of two-phase flow in the core.

Numerical simulation and analysis of solid-liquid two-phase flow in centrifugal pump

2013 ◽  
Vol 26 (1) ◽  
pp. 53-60 ◽  
Author(s):  
Yuliang Zhang ◽  
Yi Li ◽  
Baoling Cui ◽  
Zuchao Zhu ◽  
Huashu Dou
Keyword(s):  
Numerical Simulation ◽  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Two Phase ◽  
Solid Liquid

Combined experimental and computational investigation of the effect of coating on operation characteristics of solid–liquid two-phase flow centrifugal pump

2020 ◽  
pp. 2150062
Author(s):  
Yong Wang ◽  
Jie Chen ◽  
Lei Xie ◽  
Hou-Lin Liu ◽  
Kai-Kai Luo
Keyword(s):  
Centrifugal Pump ◽  
Coating Thickness ◽  
Pressure Fluctuation ◽  
Two Phase Flow ◽  
Internal Flow ◽  
Radial Force ◽  
Phase Flow ◽  
Two Phase ◽  
Solid Liquid ◽  
Operation Characteristics

The objective of this paper is to apply combined experimental and computational modeling to investigate the influence of different coating thickness on the operation characteristics of solid–liquid two-phase flow centrifugal pump. According to the characteristics of sediment flow in the Yellow River Basin, the effects of polyurethane coating thickness on the energy performance and pressure fluctuation are analyzed under the condition of solid–liquid two-phase flow and clean water. Meanwhile, the internal flow characteristics and radial force of the coated pump under the condition of solid–liquid two-phase flow are studied. The results show that the blade inlet and outlet of impeller are easy to wear, and the pressure fluctuation at the outlet of the model pump can be reduced by spraying proper coating thickness. The model pump with coating increases the low-speed zone of internal flow, which is mainly due to the increase of the viscous bottom layer area. The variation amplitude of radial force in sediment-laden water decreases with the increase of coating thickness.

scholarly journals Startup Characteristics of a Centrifugal Pump Delivering Gas-Liquid Two-Phase Flow

2014 ◽  
Vol 6 ◽  
pp. 782619 ◽  
Author(s):  
Yu-Liang Zhang ◽  
Jun-Jian Xiao ◽  
Jian-Ping Yu ◽  
Ying-Yu Ji
Keyword(s):  
Centrifugal Pump ◽  
Two Phase Flow ◽  
Pure Water ◽  
Internal Flow ◽  
Phase Flow ◽  
Centrifugal Pumps ◽  
Two Phase ◽  
Transient Flows ◽  
The Difference ◽  
Startup Period

The transient performance of centrifugal pumps during the startup period has drawn more and more attention in recent years due to urgent engineering needs. In order to make certain the transient startup characteristics of a high specific-speed prototype centrifugal pump delivering the gas-liquid two-phase flow, the transient flows inside the pump are numerically simulated during the startup period using the dynamic slip region method in this paper. The results show that the difference in heads mainly focuses on the later stage of the startup period when the pump is used to transmit the pure water and the gas-liquid two-phase flow, respectively. The existence of the gas phase makes the head less than that of delivering pure water. The nondimensional head coefficient is very high at the very beginning of the startup period and then quickly drops to a stable value. The continuous variation of the attack angle at the leading edges of blades is the main reason for evolution of the internal flow field during the startup period.

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