Influence of Blade Outlet Angle and Blade Thickness on Performance and Internal Flow Conditions of Mini Centrifugal Pump

Shigemitsu, Toru,Fukutomi, Junichiro,Kaji, Kensuke Korean Society for Fluid machinery 2011 International journal of fluid machinery and syste Vol.4 No.3

Mini centrifugal pumps having a diameter smaller than 100mm are employed in many fields; automobile radiator pump, ventricular assist pump, cooling pump for electric devices and so on. Further, the needs for mini centrifugal pumps would become larger with the increase of the application of it for electrical machines. It is desirable that the mini centrifugal pump design be as simple as possible as precise manufacturing is required. But the design method for the mini centrifugal pump is not established because the internal flow condition for these small-sized fluid machines is not clarified and conventional theory is not suitable for small-sized pumps. Therefore, we started research on the mini centrifugal pump for the purpose of development of high performance mini centrifugal pumps with simple structure. Three types of rotors with different outlet angles are prepared for an experiment. The performance tests are conducted with these rotors in order to investigate the effect of the outlet angle on performance and internal flow condition of mini centrifugal pumps. In addition to that, the blade thickness is changed because blockage effect in the mini centrifugal pump becomes relatively larger than that of conventional pumps. On the other hand, a three dimensional steady numerical flow analysis is conducted with the commercial code (ANSYS-Fluent) to investigate the internal flow condition. It is clarified from the experimental results that head of the mini centrifugal pump increases according to the increase of the blade outlet angle and the decrease of the blade thickness. In the present paper, the performance of the mini centrifugal pump is shown and the internal flow condition is clarified with the results of the experiment and the numerical flow analysis. Furthermore, the effects of the blade outlet angle and the blade thickness on the performance are investigated and the internal flow of each type of rotor is clarified by the numerical analysis results.

Effects of the number of inducer blades on the anti-cavitation characteristics and external performance of a centrifugal pump

XiaoMei Guo,ZuChao Zhu,BaoLing Cui,GaoPing Shi 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.7

Installing an inducer upstream of the main impeller is an effective approach for improving the anti-cavitation performance of a highspeed centrifugal pump. For a high-speed centrifugal pump with an inducer, the number of inducer blades can affect its internal flow and external performance. We studied the manner in which the number of inducer blades can affect the anti-cavitation characteristics and external performance of a centrifugal pump. We first use the Rayleigh-Plesset equation and the mixture model to simulate the vaporliquid flow in a centrifugal pump with an inducer, and then predict its external performance. Finally, we tested the external performance of a centrifugal pump with 2-, 3- and 4-bladed inducers respectively. The results show that the simulations of external performance in a centrifugal pump are in accordance with our experiments. Based on this, we obtained vapor volume fraction distributions for the inducer, the impeller, and in the corresponding whole flow parts. We discovered that the vapor volume fraction of a centrifugal pump with a 3-bladed inducer is less than that of a centrifugal pump with 2- or 4-bladed inducers, which means that a centrifugal pump with a 3-bladed inducer has a better external and anti-cavitation performance.

Design and CFD analysis of screw centrifugal pump model

Ming Guo,Zhenmu Chen,최영도 한국마린엔지니어링학회 2019 한국마린엔지니어링학회지 Vol.43 No.8

As a new kind of sewage pump, the screw centrifugal pump combines the advantages of screw pump and centrifugal pump. Compared with the traditional sewage pump, this new type of screw centrifugal pump demonstrates a better performance, such as less abrasion, damage and higher efficiency. It is prospective to investigate more deeply on the screw centrifugal pump. In the past, the screw centrifugal pump usually was designed by the one-dimensional theory, the hydraulic design process is similar to a normal centrifugal pump. However, because of the long trap angle and blade rotation, it is easy to commit errors in the one-dimensional design process. In this study, the general blade screw lines of hub and shroud are analyzed. The profile equations of blade screw lines were established using polar coordinate. The entire design process was discussed in detail. Moreover, the computational fluid dynamics (CFD) method has been adopted to conduct numerical simulations to investigate the internal flow characteristics of the screw centrifugal pump model and validate the performance of the newly designed screw centrifugal pump model.

Performance Prediction of Vertical Submersible Centrifugal Slurry Pump

Lal Gopal Das,Prasanta Kumar Sen,Timir Kanti Saha,Chanda, Arunabha 한국유체기계학회 2010 International journal of fluid machinery and syste Vol.3 No.2

Performance prediction methodology for centrifugal submersible slurry pump has been presented in this paper. An in-depth study on various energy-head losses occurring through the pump flow in rotating reference frame has been carried out in this research work. Head-flow characteristics of the centrifugal pump have been accomplished in two stages. First performance of the centrifugal pump with clear water has been predicted by analyzing and deducting head losses from the theoretical head. Effects of solid particles size, specific gravity and concentration on pump slurry flow have been investigated. Additional head losses due to solid particles in the slurry have been predicted, analyzed and then deducted from clear water head to establish the performance of centrifugal slurry pump. The performance of centrifugal slurry pump has been predicted at with accuracy of 88 to 90 % for solid concentration of 18 % to 5 % by volume.

배부식 동력분무기용 소형원심펌프 개선

정태상,황광성,김태규,김명규 진주산업대학교 2001 산업과학기술연구소보 Vol.- No.8

The purpose of this study was to improve the water leakage and power efficiency of the pump. The results obtained from this study which was conducted to develop a small pump through theoretical analysis, making a prototype pump and performance tests were as follows. 1. In the pump efficiency of the small pump according to the types of vortex chamber, volute type was higher than cylindrical type. 2. Inner and outer angle of impeller vane being suitable for small pump with high speed DC motor were 20 and 24 degree respectively. 3. Contents of improving the pump were to manufacture the impeller vane preciously, to make a streamline shape of impeller and reduction of the gap between pump case and impeller to reduce the friction from water flow and to prevent water leakage by means of changing the inserting method of O-ring, fitting the copper bush and filling grease into the gap of case, to change a jaw clutch instead of direct shaft connection of impeller and DC motor and to design and make the electric control circuit. 4. Under the condition of domestic test regulations which pumping pressure is 1.2㎏/㎠ and flow rate is 1200㎤/min, the continuous spraying time of newly designed prototype pump was 200 minutes which was delayed the time for 60 minutes comparing with conventional pump. And the pump efficiency of prototype was 34% which was 23% higher than that of conventional pump.

Investigation on the effect of slot pulse jet on centrifugal pump performance

Renhui Zhang,Lichen Yun 한국유체기계학회 2018 International journal of fluid machinery and syste Vol.11 No.2

To improve centrifugal pump cavitation performance, the slot pulse jet pump is proposed. The slot is designed directly on the impeller shroud near the suction side of the blade leading edge. The slots are alternately blocked by the cambered prominence, which is designed at the impeller front side chamber along the circumferential direction. The leakage flow from the front side chamber flows into the slot alternately, and the pulse jet is formed near the blade inlet. Because of the strong shear, the pulse jet is more efficient than steady jet in terms of energy transmission. Based on the numerical simulation, the hydraulic performances of the slot pulse jet pumps with two different pulse frequencies are compared with the slot steady jet pump. The calculation result shows that with the increase of flow rate, the head and efficiency of the three kinds of pumps are basically the same. The cavitation performance of slot pulse jet pump is better than that of slot steady jet pump, especially for slot pulse jet pump Ⅱ. The distribution of pressure difference acted on the slot appears to be jagged, and the pulse frequency is consistent with shaft frequency or its harmonic frequency. The amplitude of the pressure fluctuation on slot jet pump Ⅱ is much higher than that of the slot pulse jet pump Ⅰ. The vapor volume distribution in the middle span of the impeller for slot pulse jet pump is less than that of slot steady jet pump. So, the pulse jet is an effective way to further improve the cavitation performance of slot steady jet pump, and NPSHr is significantly decreased, especially at design condition.

용적형 펌프를 추가한 소방자동차용 소방펌프의 성능 인정기준에 관한 연구

한용택,성기찬,민세홍 한국화재소방학회 2016 한국화재소방학회논문지 Vol.30 No.1

본 연구는 2012년도에 제정된 원심펌프 기준에 바탕을 둔 소방자동차용 소방펌프의 성능 인정 기준에 각종 초고층 건물의 화재 및 대형화재에 대비하기 위한 고압 및 대용량의 방수 능력을 가진 용적형 펌프의 인정기준 추가에 관한 내용이다. 용적형 펌프의 실험을 바탕으로 V-1, 2, 3급의 3가지에 대한 성능에 대하여 인정기준을 제정하였으며 펌프의 효율은 원심펌프형과 동일한 65% 이상의 성능을 요구하는 인정기준이 포함 되었다. 방수압력은 1.5 MPa~2.5MPa 사이의값을 유량은 최소 0.31 m3/min에서 최대 3.0 m3/min의 방수량의 성능을 요구하는 것으로 제정되었다. 또한, 구조적으로체절압력을 조절해야하는 용적형 펌프 특성상 릴리이프 밸브에 대한 부분이 추가되었으며 이물질로 인한 펌프 내부의 파손을 방지하기 위한 스트레이너 설치 및 진공펌프 없이 작동하는 용적형 펌프와 원심펌프와의 차이점을 포함하고 있다. 이와같은 용적형 펌프의 인정기준 부분 추가로 인하여 초고층 빌딩 및 대형화재에서의 화재진압에 있어서 보다 다양한화재 진압용 소방 장비의 선택과 능동적인 대응을 할 수 있을 것으로 기대되며, 이와같은 인정기준은 2016년 1월 제정되었다. Positive displacement pumps with high pressure and water capacity are used large fires in various high-rise buildings. This study provides information for a performance approval standard of fire pumps for fire trucks based on centrifugalpump standards enacted in 2012. An experiment was conducted with a positive displacement pump for three levels of performancefrom the approval standard (V-1, 2, and 3). The efficiency of the pump was included in the reference, whichrequires the approval of 65% performance, the same as a centrifugal pump. The water pressure is between 1.5 and 2.5MPa, and the required flow rate was established as at least 0.31 m3/min and up to 3.0 m3/min. A relief valve was added toadjust the shut-off pressure due to the structural characteristics of the positive displacement pump. A strainer was alsoinstalled to prevent damage to the inside of the pump due to foreign matter. However, the strainer includes a differencefrom the positive displacement pump to operate without a vacuum pump and the centrifugal pump. This is due to theadditional approval standard portion of the positive displacement pump, which is expected to be selected for more varietyof fire-fighting equipment and proactive responses to fire suppression in a high-rise buildings and large fires. In conclusion,this approval standard was enacted in January 2016.

Cavitation Diagnosis Method for Centrifugal Pumps based on Agglomerative Hierarchical Clustering Algorithm

Hai Ming Huang,Yan Liu,Denghao Wu,Yue Zhong Wu,Tian Xin Wu 한국유체기계학회 2023 International journal of fluid machinery and syste Vol.16 No.1

Cavitation in the pump induces vibration and noise, which leads to the degradation of pump performance and damage to the impeller. Therefore, it is of great significance to accurately identify the cavitation state of the centrifugal pump. To determine the cavitation state using the vibration characteristic frequency of the centrifugal pump, it is necessary to accurately identify the characteristic frequency due to the noise's effect. Therefore, a cavitation fault diagnosis method of centrifugal pump based on a cohesive hierarchy algorithm was proposed. Firstly, Singular Value Decomposition (SVD) is used to de-noise the vibration signal. Then the root means square of the vibration signal after de-noising is obtained as the eigenvalue of the vibration signal. Secondly, the hierarchical clustering algorithm is used to classify the vibration eigenvalues and accurately identify the non-cavitation and cavitation states of centrifugal pumps. Finally, through experimental tests, the method can effectively and quickly identify the cavitation state of the centrifugal pump, with an accuracy of 95%. The study provides a new way for rapidly diagnosing centrifugal pump cavitation

Influence of Blade Number on Performance and Internal Flow Condition of Centrifugal Pump for Low Viscous Fluid Food

Toru Shigemitsu,Eito Nakaishi,Machi Maeda,Yusuke Araki 한국유체기계학회 2021 International journal of fluid machinery and syste Vol.14 No.1

There are many kinds of the fluid food transportation pumps depending on the characteristics of the fluid, i.e. a sanitary pump made from stainless steel, a screw pump and so on. A centrifugal pump was adopted as a fluid food pump in this research because it makes the stable continuous transportation of fluid food and the structure of the pump is simple compared to positive displacement pumps. The purpose of this research is to investigate the influence of the blade number on the pump performance and internal flow to enrich the pump design data for low viscous fluid food. The centrifugal pump with an open impeller was used and six impellers having the different blade number were prepared. Performance test using an experimental apparatus was conducted and the numerical analysis was also carried out. In the numerical analysis, the commercial software ANSYS-CFX16.2 was used. The head, shaft power and efficiency obtained by the numerical analysis, are almost the same with the experimental results. The head and shaft power increase with the increase of the blade number. The shear rate, which is concerned to fluid food quality, is high near the inlet region of the blade-to-blade passage for all types of blades. The shear rate of each type of the blade is discussed based on the numerical analysis results and relations between the blade number and shear rate are clarified.

Performance and Internal Flow Condition of Mini Centrifugal Pump with Splitter Blades

Shigemitsu, Toru,Fukutomi, Junichiro,Kaji, Kensuke,Wada, Takashi Korean Society for Fluid machinery 2013 International journal of fluid machinery and syste Vol.6 No.1

Mini centrifugal pumps having a diameter smaller than 100mm are employed in many fields. But the design method for the mini centrifugal pump is not established because the internal flow condition for these small-sized fluid machines is not clarified and conventional theory is not suitable for small-sized pumps. Therefore, mini centrifugal pumps with simple structure were investigated by this research. Splitter blades were adopted in this research to improve the performance and the internal flow condition of mini centrifugal pump which had large blade outlet angle. The original impeller without the splitter blades and the impeller with the splitter blades were prepared for an experiment. The performance tests are conducted with these rotors in order to investigate the effect of the splitter blades on performance and internal flow condition of mini centrifugal pump. On the other hand, a three dimensional steady numerical flow analysis is conducted with the commercial code (ANSYS-CFX) to investigate the internal flow condition in detail. It is clarified from experimental results that the performance of the mini centrifugal pump is improved by the effect of the splitter blades. Blade-to-blade low velocity regions are suppressed in the case with the splitter blades and total pressure loss regions are decreased. The effects of the splitter blades on the performance and the internal flow condition are discussed in this paper.