Influence of Blade Wrap Angle on the Hydrodynamic Radial Force of Single Blade Centrifugal Pump

To investigate the effect of blade wrap angle on the hydrodynamic radial force of a single blade centrifugal pump, numerical simulation is conducted on the pumps with different blade wrap angles. The effect of the wrap angle on the external characteristics and the radial force of a single blade centrifugal pump was analyzed according to the simulation result. It is found that, with the increase of the blade wrap angle, the head and efficiency of the single blade centrifugal pump are improved, the H-Q curve becomes steeper, and the efficiency also increased gradually, while the high-efficiency area is narrowed. The blade wrap angle has a great effect on the radial force of the single blade centrifugal pump. When the blade wrap angle is less than 360°, the horizontal component of the radial force is negative and the value is reduced with the increase of the wrap angle of the blade. When the wrap angle is larger than 360°, the horizontal component of the radial force is positive and the value increases with the increase of the wrap angle. Under part-loading conditions, the radial force of the single blade pump is significantly reduced with the increase of the blade wrap angle. When the wrap angle is smaller than 360°, the radial force decreases with the flow rate increase. In the condition that the wrap angle is larger than 360°, the radial force increases with the flow rate increase.

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Research on effects of blade wrap angle on the centrifugal pump performance

Advances in Energy Equipment Science and Engineering ◽

10.1201/b19126-423 ◽

2015 ◽

pp. 2197-2200

Author(s):

Shuting Ge ◽

Wenwu Song

Keyword(s):

Centrifugal Pump ◽

Pump Performance ◽

Wrap Angle ◽

Blade Wrap Angle

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Numerical Investigation of an Open-Design Vortex Pump with Different Blade Wrap Angles of Impeller

Processes ◽

10.3390/pr8121601 ◽

2020 ◽

Vol 8 (12) ◽

pp. 1601

Author(s):

Xiongfa Gao ◽

Ting Zhao ◽

Weidong Shi ◽

Desheng Zhang ◽

Ya Shi ◽

...

Keyword(s):

Flow Rate ◽

Front Face ◽

Structural Parameter ◽

Pump Efficiency ◽

Impeller Blade ◽

Open Design ◽

Vortex Pump ◽

Lateral Cavity ◽

Wrap Angle ◽

Blade Wrap Angle

The blade wrap angle of impeller is an important structural parameter in the hydraulic design of open-design vortex pump. In this paper, taking a vortex pump with a cylindrical blade structure as the research object, two kinds of different blade wrap angle of vortex pump impellers are designed. The experiment and numerical simulation research is carried out, and the results of external characteristics and internal flow field are obtained under different flow rate. The results show that when ensuring that other main structural parameters remain unchanged, the efficiency and head of open-design vortex pump increase with the blade wrap angle decreases. In the case of blade wrap angle increasing, the length of rotating reflux back from lateral cavity to inlet is longer. For the same type of vortex pump, the length of rotating reflux to inlet decreases with the increase of flow rate. At the inlet area of impeller front face, there is an area where liquid flows back to the lateral cavity. The volute section shows that after passing through the impeller and lateral cavity, the liquid is discharged to the pump outlet with strong spiral strength. It is found that the blade wrap angle decreases and the shaft power increases, while the pump efficiency increases. The impeller blade wrap angle of vortex pump can be considered to select a smaller value.

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Clocking effect in a centrifugal pump with a vaned diffuser

Modern Physics Letters B ◽

10.1142/s0217984920502863 ◽

2020 ◽

Vol 34 (26) ◽

pp. 2050286

Author(s):

Fen Lai ◽

Xiangyuan Zhu ◽

Yongqiang Duan ◽

Guojun Li

Keyword(s):

Centrifugal Pump ◽

Flow Rate ◽

Pressure Loss ◽

Total Pressure ◽

Radial Force ◽

Design Flow ◽

Total Pressure Loss ◽

Inlet Section ◽

Centrifugal Pumps ◽

Installation Angle

The performance and service life of centrifugal pumps can be influenced by the clocking effect. In this study, 3D numerical calculations based on the k-omega shear stress transport model are conducted to investigate the clocking effect in a centrifugal pump. Time-averaged behavior and transient behavior are analyzed. Results show that the optimum diffuser installation angle in the centrifugal pump is [Formula: see text] due to the minimum total pressure loss and radial force acting on the impeller. Total pressure loss, particularly in the volute, is considerably influenced by the clocking effect. The difference in total pressure loss in the volute at different clocking positions is 2.75 m under the design flow rate. The large total pressure loss in the volute is primarily caused by the large total pressure gradient within the vicinity of the volute tongue. The radial force acting on the impeller is also considerably affected by the clocking effect. When the diffuser installation angle is [Formula: see text], flow rate fluctuations in the volute and impeller passage are minimal, and flow rate distribution in the diffuser passage is more uniform than those in other diffuser installation angles. Moreover, static pressure fluctuations in the impeller midsection and the diffuser inlet section are at the minimum value. These phenomena explain the minimum radial force acting on the impeller. The findings of this study can provide a useful reference for the design of centrifugal pumps.

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Efficiency improvement and evaluation of a centrifugal pump with vaned diffuser

Advances in Mechanical Engineering ◽

10.1177/1687814019825904 ◽

2019 ◽

Vol 11 (3) ◽

pp. 168781401982590 ◽

Cited By ~ 2

Author(s):

Kai Wang ◽

Yu-cheng Jing ◽

Xiang-hui He ◽

Hou-lin Liu

Keyword(s):

Centrifugal Pump ◽

Axial Force ◽

Flow Rate ◽

Pressure Pulsation ◽

Energy Performance ◽

Radial Force ◽

Design Flow ◽

Vaned Diffuser ◽

Original Scheme ◽

Design Flow Rate

In order to enhance the efficiency of centrifugal pump, the structure of a centrifugal pump with vaned diffuser, whose specific speed is 190, was numerically improved by trimming back-blades of impeller and smoothing sharp corner in annular chamber. The energy performance, the internal flow field, the axial force, the radial force, and the pressure pulsation of the pump were analyzed. Results show that efficiency of the improving scheme 1 under the design flow rate is 77.47%, which can balance 69.82% of the axial force, while efficiency of the improving scheme 2 under the design flow rate is the maximum, which could still balance 62.74% of the axial force. The pressure pulsations of the improving scheme 2 at the typical monitoring points are less than that of the improving scheme 1 and the original scheme. The difference of the radial force peak between the improving scheme 1 and the improving scheme 2 is very small. The vector distributions of the radial force of the improving scheme 1 and the improving scheme 2 are more uniform than that of the original scheme. Considering the efficiency, pressure pulsation, and axial force, experiment measurements on the improving scheme 2 were carried out to verify the effectiveness of the improvement result. Results of energy performance experiment show that efficiency of the improving scheme 2 under the design flow rate is 76.48%, which is 5.26 percentage points higher than that of the original scheme.

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Numerical study on instantaneous radial force of a centrifugal pump for different working conditions

Engineering Computations ◽

10.1108/ec-04-2019-0147 ◽

2019 ◽

Vol 37 (2) ◽

pp. 458-480

Author(s):

Xiaoqi Jia ◽

Sheng Yuan ◽

Zuchao Zhu ◽

Baoling Cui

Keyword(s):

Numerical Simulation ◽

Unsteady Flow ◽

Centrifugal Pump ◽

Working Conditions ◽

Flow Rate ◽

Pressure Pulsation ◽

Radial Force ◽

Leakage Rate ◽

Content Type ◽

Three Components

Purpose Instantaneous radial force induced from unsteady flow will intensify vibration noise of the centrifugal pump, especially under off-design working conditions, which will affect safety reliability of pump operation in severe cases. This paper aims to conduct unsteady numerical computation on one centrifugal pump; thus, unsteady fluid radial force upon the impeller and volute is obtained, so as to study the evolution law of instantaneous radial force, the internal relationship between radial force and pressure pulsation, the relationship among each composition of radial force that the impeller received and the influence of leakage rate of front and back chamber on radial force. Design/methodology/approach The unsteady numerical simulation with SST k-ω turbulence model was carried out for a low specific-speed centrifugal pump using computational fluid dynamics codes FLUENT. The performance tests and pressure tests were conducted by a closed loop system. The performance curves and the pressure distribution from numerical simulation agree with that of the experiment conducted. The unsteady pressure distributions and the instantaneous radial forces induced from unsteady flow were analyzed under different flow rates. Contribution degrees of three components of the radial force on the impeller and the relation between the radial force and leakage rate were analyzed. Findings Radial force on the volute and pressure pulsation on the volute wall have the same distribution tendency, but in contrast to the distribution trend of the radial force on the impeller. In the component of radial force that the impeller received, radial force on the blade accounts for the main position. With the decrease of flow rate, ratio of the radial force on front and back casings will be increased; under large flow rate, vortex and flow blockage at volute section will enhance the pressure and radial force fluctuation greatly, and the pulsation degree may be much more intense than that of a smaller flow rate. Originality/value This paper revealed the relation of the radial force and the pressure pulsation. Meanwhile, contribution degrees of three components of the radial force on the impeller under different working conditions as well as the relation between the radial force and leakage rate of front and rear chambers were analyzed.

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Pressure Fluctuation of the Low Specific Speed Centrifugal Pump

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.152-154.935 ◽

2012 ◽

Vol 152-154 ◽

pp. 935-939 ◽

Cited By ~ 2

Author(s):

Qiang Fu ◽

Shou Qi Yuan ◽

Rong Sheng Zhu

Keyword(s):

Centrifugal Pump ◽

Flow Rate ◽

Pressure Fluctuation ◽

High Frequency ◽

Pressure Fluctuations ◽

Radial Force ◽

Design Flow ◽

Rate Condition ◽

Low Specific Speed ◽

Specific Speed

In order to study the rules of pressure fluctuation and the radial force under different positions in a centrifugal pump with low specific speed, and to find the relationship between each other, the three-dimensional ,unsteady Reynolds-averaged Navier-stokes equations with shear stress transport turbulent models were solved. The pressure fluctuation was obtained. The results showed that the pressure fluctuations were visible. The pressure fluctuations in the volute were relatively low at the design flow rate condition. The blade passing frequency dominates the pressure fluctuations, high frequency contents were found on the outlet of impeller but no high frequency information occured in casing. The radial force on the impeller was unsteady especially at the small flow rate.

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