• 한국전산유체공학회지
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• 제6권1호
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• pp.14-20
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• 2001

The CFD analysis of the three-dimensional turbulent flow in the impeller and diffuser of an axial flow pump was performed. Not only the design point but also the off-design points were computed. The results were compared with available experimental data in terms of head generated. At the design point, the analysis accurately predicted the experimental head value. In the range of the higher flow rates, the results were also in very good agreement with the experimental data, not only in absolute value but also in term of slope. Although experimental data to be compared were not available in the range of the lower flow rates, the results well described the S-shape performance curve of the axial pump characteristic.

• International Journal of Fluid Machinery and Systems
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• 제9권4호
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• pp.370-381
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• 2016

As a single-channel pump is used for wastewater treatment, this particular pump type can prevent performance reduction or damage caused by foreign substances. However, the design methods for single-channel pumps are different and more difficult than those for general pumps. In this study, a design optimization method to improve the hydrodynamic performance of a single-channel pump impeller is implemented. Numerical analysis was carried out by solving three-dimensional steady-state incompressible Reynolds-averaged Navier-Stokes equations using the shear stress transport turbulence model. As a state-of-the-art impeller design method, two design variables related to controlling the internal cross-sectional flow area of a single-channel pump impeller were selected for optimization. Efficiency was used as the objective function and was numerically assessed at twelve design points selected by Latin hypercube sampling in the design space. An optimization process based on a radial basis neural network model was conducted systematically, and the performance of the optimum model was finally evaluated through an experimental test. Consequently, the optimum model showed improved performance compared with the base model, and the unstable flow components previously observed in the base model were suppressed remarkably well.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2018년도 추계학술발표대회
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• pp.339-342
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• 2018

The resent work is about the design and installation of the 60 URT heat pump according to the need. This design is eco-friendly, easily available, reduces maintenance and electricity cost. The dimensions of heat pump is $1500mm{\times}500mm{\times}1940mm$ (i.e length 1500 mm, width 500 mm and height 1940 mm) is installed on site. It can be operated with automation (PID) and controlled by sensors. The performance of and heat pump is evaluated experimentally by the monitoring system.

• 한국유체기계학회 논문집
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• 제10권6호
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• pp.24-31
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• 2007

In the present study, the effects of the design factors and operating conditions on flow characteristics of a vane pump for the automotive power steering system has been analyzed numerically. An unsteady moving mesh technique with cell expansion/contraction method is used to simulate the rotation of vanes with respect to stationary inlet and outlet. As a result, the flow characteristics of the flow rate and pressure rise across the vane pump were obtained. The numerical analyses for the various design factors such as number of vanes and thickness between the rotor and camring and for various operating conditions such as rotational speed and pressure difference between inlet and outlet were extensively performed. And the results were discussed in the paper.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 1999년도 유체기계 연구개발 발표회 논문집
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• pp.333-337
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• 1999

The biggest challenge facing today manufacturing industry is better quality and high productivity. From an economic point of view, productivity is the most important parameter, as high productivity will reduce the cost. However, the customers of day are not only cost concerned, but also quality conscious. So high accuracy levels should also be achieved in the manufacturing process. This paper reports the development of a automatic design system based on AutoCAD program. 1'his work is composed of three section that are design of top down menu, impeller and casing for pump programed by AutoLISP language and runned Windows system. The developed system ultimately generates the design for a pump through AutoCAD program. In the design of the pump, it needs about 23 hours with an expert, but this system can be only 80 seconds without an expert.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2002년도 춘계학술대회논문집
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• pp.89-94
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• 2002

A commercial CFD code is used to calculate the 3-D viscous flow field within the centrifugal pump impeller. Design conditions are changed by impeller inlet(9.3mm, 12.2mm) and outlet breadth(6.65mm, 6.85mm). Numerical calculation was performed by changing flow rate from 8 to 26m$^{3}$/hr. Computation results shows that total head is increased at the larger inlet and outlet breadth than the others. And when the flow rate is increasing, the total head was decreased. The maximum efficiency of pump is shown at the design flow rate(16m$^{3}$/hr). In this study shows that the calculated results are good agreements with analysis results of design condition.

• 한국유체기계학회 논문집
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• 제14권1호
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• pp.18-23
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• 2011

The hydraulic part in reactor coolant pump consists of suction nozzle, impeller, diffuser, and discharge nozzle. Among them, impeller is required to be designed to satisfy performance requirements such as head, NPSHR, and head curve slope at design point. Present study is intended to suggest the preliminary design method sizing the impeller size to satisfy the design requirement particularly including head curve slope at design point. On a basis of preliminary design result, hydraulic components have been designed in detail by CFD and then manufactured in a reduced scale. Experiment in parallel with computational analysis has been executed in order to confirm the hydraulic performance. Comparison results show good agreement with design result, confirming the validity of design method suggested in this study.

• 한국유체기계학회 논문집
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• 제5권1호
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• pp.33-41
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• 2002

Low NPSH and high pressure pumps we widely used for turbopump systems, which have an inducer and operate at high rotating speeds. In this paper, a meanline method has been established for the preliminary design and performance prediction of pumps having an inducer for cavitating or non-cavitating conditions at design or off-design points. The method was applied for the performance prediction of a fuel pump. Predicted performances by the method are shown to be in good agreement with experimental results for cavitating and non-cavitating conditions. The established meanline method can be used for the performance prediction and preliminary design of high speed pumps which have a inducer, impeller and volute.

• 센서학회지
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• 제12권1호
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• pp.51-56
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• 2003

We describe a charge pump circuit using VCO (voltage controlled oscillator) for storing information into local memories in neural networks. The VCO is used for adjusting the output voltage of the charge pump to the reference voltage and for reducing the fluctuation generated by the clocking scheme. The charge pump circuit is simulated by using Hynix 0.35um CMOS process parameters. The proposed charge pump operates properly regardless to the temperature and the supply voltage variation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.789-791
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• 2001

이전에 개발된 Magnetic Fluid Linear Pump는 자기 회로가 솔레노이드 형식으로 자기회로의 대부분이 공극이기 때문에 자기저항이 크다. 이런 문제로 인해서 Linear Pump의 자성유체에 영향을 주는 자기장이 크지 않고 펌핑 압력은 높지 않다. 따라서 본 논문에서는 Permalloy Yoke를 이용하여 Linear Pump를 소형화하고 자기 저항을 최소화함으로써 펌핑 압력을 향상시켰다. 또한 Linear Pump의 3D해석을 통하여 Yoke의 폭, 두께, 간격에 대한 최적 크기를 계산하였다.