• International Journal of Fluid Machinery and Systems
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• v.4 no.3
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• pp.317-323
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• 2011

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.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.533-534
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• 2006

In this paper we propose a new model of a mini-pump with peristaltic motion and present the results of the finite element analysis of an electromagnetic micro actuator. The mini-pump consists of three diaphrams made of PDMS, three permanent magnets in cylinders, printed copper coils on glass substrates, and input and output port. The size of the mini-pump is $14\;{\times}\;40\;{\times}\;5.4$ mm3 and the permanent magnet diameter 6.2 mm $\times$ thickness 2 mm. The electromagnetic force applied on the magnet was about 0.84 N when the current of coils was 1 A, then the maximum displacement of the PDMS diaphram was about 2mm.

• International Journal of Fluid Machinery and Systems
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• v.6 no.1
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• pp.11-17
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• 2013

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.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3134-3138
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• 2007

The objective of this paper is to elucidate the characteristic performance of the mini-vacuum pump with various heights of eccentric shaft. The mini-diaphragm pump is composed of DC motor, eccentric shaft and diaphragm and it is operated by PCB panel. The height of eccentric shaft is changed that controls the quantities of air flow to improve the performance of vacuum pressure. This device is manufactured in order to embody the vacuum pressure with 200 mmHg. The heights of eccentric shaft which is used in present experiment are located in the range from 3 mm to 5.5 mm. The vacuum pressure distributions with each height of eccentric shaft was measured and the results were graphically depicted.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.54-60
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• 2002

A mini turbo-pump having 44mm diameter impeller for hydraulic power control have been tested to evaluate hydraulic performance and losses. The characteristics of the losses such as mechanical, friction, balancing rib losses were investigated. The investigation revealed that the friction loss is relatively large but the balancing rib loss small. It was found that the hydraulic efficiency of the pump at design point is very low($27\%$) due to low specific speed and large friction losses. A computational fluid dynamics(CFD) method also has been utilized for performance prediction of the mini turbo-pump to compare the computed results with the test data.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.775-780
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• 2008

This paper reports on the internal flow of a centrifugal mini pump working at the low flow rate operating conditions. The RNG $\kappa-\varepsilon$ turbulence model was employed to simulate the three-dimensional turbulent flow in the pump. To examine and certify the simulation results, a transparent acrylic centrifugal mini pump model which is suitable for PIV measurement has been developed. The tongue region and the passages region between blades were investigated using PIV. In order to eliminate the effect of refraction on the area closed to the wall and increase the measurement accuracy, the fluorescent particles were scatted into the working fluid with the tracing particles. It is found from the calculation and PIV measurement results that there is a large area of recirculation flow near the tongue at low flow rate operating conditions. The computationally predicted water head using the $\kappa-\varepsilon$ turbulence model at low flow rate operating conditions are in very good agreement with the experimentally measured water head and the mean velocity distributions at investigation area obtained by PIV and calculation showed a satisfactory agreement as well. Meanwhile, the results of PIV measurements show that the flow status in one passage is different to another. And for capturing the internal flow detail information, the $\kappa-\varepsilon$ turbulence model is not very suitable.

• Parasites, Hosts and Diseases
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• v.22 no.2
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• pp.203-208
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• 1984

This experiment shows cellular and humoral immune responses induced by soluble egg antigen of Schistosoma manscni, that is, change of the number of peripheral blood eosinophil, delayed hypersensitivity measured by the degree of ear swelling, granulomatous change of liver tissue and elevation of serum antibody titer by ELISA. SEA was given continuously by the insertion of a minipump into peritoneal cavity of mouse. In control group, same pump with HGG was inserted. New pump was eachansed once In two weeks and followed the result until 9 weeks after mini-pump insertion. 1. Highest peripheral blood eosinophil level was recorded at 2∼3 weeks after SEA punp insertion, 2. MaRirnum ear swelling was observed at 2 weeks arid then decreased gradually. 3. In liver tissue, several granulomas without egg were formed at 4 weeks. 4. Serum antibody titer was eleyated from 4 weeks after SEA pump insertion.

• Nuclear Engineering and Technology
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• v.20 no.1
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• pp.47-53
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• 1988

The objective of this study is to evaluate the reliability of the High Head Safety Injection System (HHIS) of KNU 5, 6, 7 and 8 following the removal of safety injection signal (s-signal) from the mini-flow bypass line valves of charging/safety injection pumps. The unavailability of HHSIS and the rupture probability of a charging/safety injection pump have been computed for two different cases; with s-signal on and removed. The results show that when the s-signal is removed from the mini-flow bypass line valves, the unavailability of HHSIS slightly increases while the rupture probability of a charging/safety injection pump is significantly reduced. Hence, based upon the results of this study we conclude that it is more reasonable to remove the s-signal from the mini-flow bypass line valves of KNU 5, 6, 7 and 8 in the normal plant operation. And to improve the availability of HHSIS, the modification of operational procedures and the emphasis on operator training are recommended.

• International Journal of Fluid Machinery and Systems
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• v.2 no.2
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• pp.121-126
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• 2009

The internal flow field in a centrifugal pump working at the several flow conditions has been measured by using the particle image velocimetry (PIV) technique with the laser induced fluorescence (LIF) particles and the refractive index matched (RIM) facilities. The impeller of the centrifugal pump has an outlet diameter in 100mm, and consists of six two-dimensional curvature backward swept blades of constant thickness. Measured results give reliable flow patterns in the pump. It is obvious that application of LIF particle and RIM are the key methods to obtain the right PIV measured results in pump internal flow.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.1167-1171
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• 1993

A highly efficient hydropneumatic water supply system type BGY is designed and built in accordance with ISO standard. The technical features of BYG type pump unit can be summarized as follows: - reduce hydropneumatic tank capacity at the ratio of 1/10 - 1/30 compared with conventional method. - ISO standard pumps can be used. - the development of highly efficient water supply system type BYG is based on long-term experiences with the proven constant pressure water supply technique which minimize pressure fluctuation, rapid pilsation, etc. The text contains the operation principle of BYG type water supply system, introduction of closed cycle control process focused on Mini PC and experimental results of type BYG-IVS-90x45.