Effect of Surfactant Additives on Centrifugal Pump Performance

2005 ◽  
Vol 128 (4) ◽  
pp. 794-798 ◽  
Author(s):  
Satoshi Ogata ◽  
Asano Kimura ◽  
Keizo Watanabe

Performance of a centrifugal pump when handling surfactant solutions was measured experimentally. It was clarified that the pump efficiency with surfactant solutions was higher than that with tap water and increased with an increase in surfactant concentration. The value of maximum flow rate also increased. The total pump head increased with an increase in concentration, and the shaft power decreased with a decrease in the impeller rotating speed. There was an optimal temperature, which maximizes the efficiency. By combining the data for the piping section and for the pump efficiency, it is possible to accurately predict the energy savings of the pumping power in the pipeline system.

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.


Author(s):  
Katsumi Chiba ◽  
Yukio Ito ◽  
Kazunori Kobayashi ◽  
Atsushi Kawamorita

In many manufacture fields, such as foods, medical supplies, cosmetics, lubricants and paints of present in used, a Shear pump successively takes advantage of such cavitation effects as a large amount of cavitation bubbles and the associated impulsive high shock pressures, to the mixing, to the stirring and to the emulsion. In this study, to estimate the behavior of the cavitation effects in the shear pump, we precisely evaluate the performance. Although the performance of the shear pump, that is the total head Hp, the shaft power Ps, the pump efficiency η — the flow rate Q curves, is very similar to those of the centrifugal pump tested in tap water, they are much different from that in higher viscosity solutions of 500 cP.


2021 ◽  
Vol 5 (1) ◽  
pp. 80-88
Author(s):  
Nur Hanna Khairul Anuar ◽  
Mohd Nizar Mhd Razali ◽  
Mohamad Rusydi Mohamad Yasin ◽  
Musfirah Abdul Hadi ◽  
Abdul Nasir Abd. Ghaffar

Viscosity is one of the factors affecting the performance of the centrifugal pump. A centrifugal pump is a device that used driven motor called impeller to move fluid by rotational energy. This thesis is about the analysis of the performance of the centrifugal pump when transferring viscous liquids. For this project, the objective is to design and fabricate a device that can pump liquid with various viscosity using centrifugal pump. The liquids used in the experiment are comprised of a mixture of detergent and water with different ratio to alter the viscosity. The viscosity is being identified by the usage of Zahn Cup Method with the temperature kept constant at 26 °C throughout the experiment. The performance of the centrifugal pump is being investigated by four parameters which is the flowrate, Total Dynamic Head (TDH), power and efficiency. The performance of the centrifugal pump can be accessed by altering the pump shaft speed in order to get various reading for the flow rate. In order to alter the pump shaft speed, the usage of motor with Variable Frequency Drive (VFD) is implemented. The values for the flowrate and pump shaft power are measured by flowmeter and Variable Frequency Drive (VFD). The Total Dynamic Head (TDH), hydraulic power and pump efficiency is calculated based on the reading of the flowmeter and pump shaft power displayed at Variable Frequency Drive (VFD). At the end of this project, the pump performance while pumping different viscous liquids at different flowrates is being identified.


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.


2018 ◽  
Vol 140 (11) ◽  
Author(s):  
Wang Jian ◽  
Wang Yong ◽  
Liu Houlin ◽  
Si Qiaorui ◽  
Matevž Dular

Cavitation has bothered the hydraulic machinery for centuries, especially in pumps. It is essential to establish a solid way to predict the unsteady cavitation evolution with considerable accuracy. A novel cavitation model was proposed, considering the rotating motion characteristic of centrifugal pump. Comparisons were made with three other cavitation models and validated by experiments. Considerable agreements can be noticed between simulations and tests. All cavitation models employed have similar performance on predicting the pump head drop curve with proper empirical coefficients, and also the unsteady cavitation evolution was well solved. The proposed rotating corrected-based cavitation model (rotating based Zwart-Gerber-Belamri (RZGB)) obtained identical triangle cavity structure with the experiment visualizations, while the others also got triangle structure but with opposite direction. The maximum flow velocity in the impeller passage appears near the shroud, contributing to the typical triangle cavity structure. A preprocessed method for instant rotating images was carried out for evaluating the erosion risk area in centrifugal pump, based on the standard deviation of gray level. The results imply that the unsteady rear part of the attached cavity is vulnerable to be damaged, where the re-entrant flow was noticed. This work presented a suitable cavitation model and reliable numerical simulation approach for predicting cavitating flows in centrifugal pump.


2018 ◽  
Vol 1 (2) ◽  
pp. 24-39
Author(s):  
A. Farid ◽  
A. Abou El-Azm Aly ◽  
H. Abdallah

Cavitation in pumps is the most severe condition that centrifugal pumps can work in and is leading to a loss in their performance.  Herein, the effect of semi-open centrifugal pump side clearance on the inception of pump cavitation has been investigated.  The input pump pressure has been changed from 80 to 16 kPa and the pump side clearance has been changed from 1 mm to 3 mm at a rotation speed of 1500 rpm. It has been shown that as the total input pressure decreased; the static pressure inside the impeller is reduced while the total pressure in streamwise direction has been reduced, also the pump head is constant with the reduction of the total input pressure until the cavitation is reached. Head is reduced due to cavitation inception; the head is reduced in the case of a closed impeller with a percent of 1.5% while it is reduced with a percent of 0.5% for pump side clearance of 1mm, both are at a pressure of 20 kPa.   Results also showed that the cavitation inception in the pump had been affected and delayed with the increase of the pump side clearance; the cavitation has been noticed to occur at approximate pressures of 20 kPa for side clearance of 1mm, 18 kPa for side clearances of 2mm and 16 kPa for 3mm.


Machines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 60
Author(s):  
Khaled Alawadhi ◽  
Bashar Alzuwayer ◽  
Tareq Ali Mohammad ◽  
Mohammad H. Buhemdi

Since centrifugal pumps consume a mammoth amount of energy in various industrial applications, their design and optimization are highly relevant to saving maximum energy and increasing the system’s efficiency. In the current investigation, a centrifugal pump has been designed and optimized. The study has been carried out for the specific application of transportation of slurry at a flow rate of 120 m3/hr to a head of 20 m. For the optimization process, a multi-objective genetic algorithm (MOGA) and response surface methodology (RSM) have been employed. The process is based on the mean line design of the pump. It utilizes six geometric parameters as design variables, i.e., number of vanes, inlet beta shroud, exit beta shroud, hub inlet blade draft, Rake angle, and the impeller’s rotational speed. The objective functions employed are pump power, hydraulic efficiency, volumetric efficiency, and pump efficiency. In this reference, five different software packages, i.e., ANSYS Vista, ANSYS DesignModeler, response surface optimization software, and ANSYS CFX, were coupled to achieve the optimized design of the pump geometry. Characteristic maps were generated using simulations conducted for 45 points. Additionally, erosion rate was predicted using 3-D numerical simulations under various conditions. Finally, the transient behavior of the pump, being the highlight of the study, was evaluated. Results suggest that the maximum fluctuation in the local pressure and stresses on the cases correspond to a phase angle of 0°–30° of the casing that in turn corresponds to the maximum erosion rates in the region.


Author(s):  
Ning Zhang ◽  
Bo Gao ◽  
Chao Li ◽  
Dan Ni ◽  
Guoping Li

Effects of the staggered blades on unsteady pressure pulsations of a centrifugal pump with a specific speed ns=147 are investigated by the numerical simulation method. The obtained results are compared with the original blades. To clarify the resulting effects, eight monitoring points are used to extract pressure signals at three typical working conditions, and component at the blade passing frequency fBPF is emphasized. Results show that the pump efficiency and head will be reduced by the staggered blades, and at the nominal flow rate, the reduction is about 1.5% from comparison with the original blades. For all the eight points, the staggered blades contribute to the reduction of pressure amplitudes at fBPF when the pump works at three flow rates. The averaged reduction is 15.5% at the nominal flow rate. However, the negative effect on the second harmonic of fBPF will be caused by the staggered blades, and the corresponding pressure amplitude will increase at 2fBPF. It means that the pressure pulsation energy will be redistributed among the discrete components in pressure spectrum by the staggered blades. From the TKE distribution, it is found that the TKE values on the blade pressure side will be significantly affected by the staggered blades.


2001 ◽  
Author(s):  
Satoshi Ogata ◽  
Keizo Watanabe

Abstract The flow around a circular cylinder in surfactant solution was investigated experimentally by measurement of the pressure and velocity profiles in the Reynolds number range 6000 < Re < 50000. The test surfactant solutions were aqueous solutions of Ethoquad O/12 (Lion Co.) at concentrations of 50, 100 and 200 ppm, and sodium salicylate was added as a counterion. It was clarified that the pressure coefficient of surfactant solutions in the range of 10000 < Re < 50000 at the behind of the separation point was larger than that of tap water, and the separation angle increased with concentration of the surfactant solution. The velocity defect in surfactant solutions behind a circular cylinder was smaller than those in tap water. The drag coefficients of a circular cylinder in surfactant solutions were smaller than those of tap water in the range 10000 < Re < 50000, and no drag reduction occurred at Re = 6000. The drag reduction ratio increased with increasing concentration of surfactant solution. The maximum drag reduction ratio was approximately 35%.


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