• The KSFM Journal of Fluid Machinery
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• v.14 no.5
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• pp.12-17
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• 2011

The seawater lift pump system is responsible for maintaining the open canal level to provide the suction flow of circulating water pump at the set point. The objective of this paper is to design a 2-stage mixed flow pump (for seawater lifting) by inverse design method and to evaluate the overall performance and the local flow fields of the pump by using a commercial CFD code. Rotating speed of the impeller is 1,750 rpm with the flow rate of 2,700 $m^3$/h. Finite volume method with structured mesh and realized k-${\varepsilon}$ turbulent model is used to guaranty more accurate prediction of turbulent flow in the pump impeller. The numerical results such as static head, brake horse power and efficiency of the mixed flow pump are compared with the design data. The simulated results are good agreement with the design data less 3% error.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.6
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• pp.242-247
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• 2016

This study analyzed the energy consumption of a building pump system that was originally equipped with a primary-secondary zone pump system. Using the HYSYS program the energy consumption of the primary pump system was compared with the primary-secondary zone pump system. The primary-secondary zone pump system consumes less energy than the originally designed primary pump system. When the distance between the machine room and each building is assumed to be equal, the primary pump system can be more efficient than the primary-secondary zone pump system with decreasing the distance. When the distance is 120 m, the primary system consumes less total annual energy than the primary-secondary zone pump system and saves 2,773 kWh. The suggested energy evaluation program can be useful if the designer seeks a more efficient pump system.

• International Journal of Fluid Machinery and Systems
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• v.4 no.1
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• pp.133-139
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• 2011

In this paper, Based on Two-dimensional Flow Theory, adopting quasi-orthogonal method and point-by-point integration method to design the impeller of the low specific speed centrifugal pump by code, and using RANS (Reynolds Averaged N-S) Equation with a standard k-${\varepsilon}$ two-equation turbulence model and log-law wall function to solve 3D turbulent flow field in the impeller of the low specific speed pump. An analysis of the influences of the blade profile on velocity distributions, pressure distributions and pump performance and the investigation of the flow regulation pattern in the impeller of the centrifugal pump are presented. And the result shows that this method can be used as a new way in low speed centrifugal pump impeller design.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.335-338
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• 2006

A Numerical study of the cavitation within a centrifugal pump is carried out using CFD commercial code, FLUENT. The objective of this study is to predict the onset of cavitation within the pump blade and the degradation in the pressure rise due to the generation and transport of vapor. A pump designed for the study is a six bladed, one-circular arc impeller design suggested by A.J. Stepanoff et al. The Steady-state calculations are performed for a wide range of flow rate without the cavitation to investigate the pump performance. The design head and efficiency show a very good agreement with the numerical results at the design flow rate. After the validation with the numerical results, the pump performance and the onset of cavitation within the blade is predicted by changing NPSH at the design flow rate.

• The KSFM Journal of Fluid Machinery
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• v.15 no.3
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• pp.39-45
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• 2012

In this study, optimization of the impeller and design of volute were carried out in order to improve the performance of a centrifugal pump. Design parameters from vane plane development for impeller design were selected, and effect of the design parameters on the performance of the pump was analyzed by using Response Surface Methodology(RSM) to optimized impeller. In addition, total pump design method was suggested by designing volute which was suitable for the optimized impeller through volute design where Stepanoff theory was applied and numerical analysis.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.556-560
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• 2011

The seawater lift pump system is responsible for maintaining the open canal level to provide the suction flow of circulating water pump at the set point. The objective of this paper is to design a 2-stage mixed flow pump(for seawater lifting) by inverse design and to evaluate the overall performance and the local flow fields of the pump by using a commercial CFD code. Rotating speed of the impeller is 1,750 rpm with the flow rate of 2,700 $m^3/h$. Finite volume method with structured mesh and Realizable ${\kappa}-{\varepsilon}$ turbulent model is used to guaranty more accurate prediction of turbulent flow in the pump impeller. The numerical results such as static head brake horse power and efficiency of the mixed flow pump are compared with the reference data. Also, the periodic condition calculation method for the mixed flow pump was carried out in order to investigate the pump performance characteristics with the modification of impeller geometry.

• Journal of Mechanical Science and Technology
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• v.20 no.10
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• pp.1626-1637
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• 2006

The pressure pulsation due to the gear geometry of the gerotor (generalized rotor) pump mainly occurs in an instant that the chamber of the gerotor enters the delivery port and leaves the suction one. Such a pressure pulsation may result in undesirable vibration and noise of pump components as well as cavitation in hydraulic system. Therefore, it is very important to examine the pressure characteristic of the gerotor pump at its design and analysis stages. In this paper, in order to reduce the pressure pulsation in the gerotor pump, the port plate with the relief grooves is designed by referring to as notch of vane pump and relief groove of piston pump. A series of the theoretical analyses on the pressure pulsation is performed in consideration of various design parameters of the port plate, including the installation positions of the port inlet/outlet and the groove width, and the operating conditions such as rotational velocity and delivery pressure.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.2 s.179
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• pp.88-96
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• 2006

A gerotor pump is suitable for oil hydraulics of machine tools, automotive engines, compressors, constructions and other various applications. Especially the pump is an essential machine element of an automotive engine to feed lubricant oil. The subject of this paper is the theoretical analysis of the internal lobe pump which is a particular type of positive displacement pump. The main components of the pump are rotors; usually the outer rotor profile is characterized by lobes with circular shape, while the inner rotor profile is determined as conjugate as the outer rotor profile. For this reason the topic presented here is the definition of the geometry of the rotors starting from the design parameters. The choice of these parameters is subject to some limitations in order to avoid cusp and loop between rotors. And the integrated system which is composed of three main modules has been developed through AutoLISP & Visual Basic and CAD considering various design parameters. It generates automatically an designed model for a general type of a gerotor pump and allows us to calculate two performances indexes commonly used for the study of positive displacement pumps: the flow rate and flow rate irregularity. Results obtained using the system enable the designer and manufacturer of oil pump to be more efficient in this field.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.6
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• pp.428-434
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• 2015

The objective of the present study is to analyze the results of the trial-test for the full-scale driving pump, which is arranged in the LCT (Large Cavitation Tunnel). Firstly, the reasons of selecting the final design pump are introduced in terms of the performance analysis in model tests. The trial-test items for the full-scale driving pump are measurements of output current/voltage at the inverter of the main motor and the flow velocity in the LCT test section. The test results show the increase in flow rate of about 10.7% and the decrease in pump head of about 26%, compared with those of final design-pump specification. The motor power has the margin of about 22%. The performance analysis for the full-scale pump is conducted using the commercial code (CFX-10). The delivered power calculated with CFX-10 shows good agreement with that extracted from the full-scale pump test. It is found that CFX-10 is useful to analyze a full-scale pump.

• International Journal of Fluid Machinery and Systems
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• v.8 no.1
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• pp.46-54
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• 2015

Thrust-ring-pump is a kind of extreme-low specific speed centrifugal pump with special structure as numerous restrictions from thrust bearing and operation conditions of hydro-generator units. Because the oil circulatory and cooling system with thrust-ring-pump has a lot of advantages in maintenance and compactness in structure, it has widely been used in large and medium-sized hydro-generator units. Since the diameter and the speed of the thrust ring is limited by the generator set, the matching relationship between the flow passage inside the thrust ring (equivalent to impeller) and oil bath (equivalent to volute) has great influence on hydrodynamic performance of thrust-ring-pump. On another hand, the head and flow rate are varying with the operation conditions of hydro-generator units and the oil circulatory and cooling system. As so far, the empirical calculation method is employed during the actual engineering design, in order to guarantee the operating performance of the oil circulatory and cooling system with thrust-ring-pump at different conditions, a collaborative hydrodynamic design and optimization is purposed in this paper. Firstly, the head and flow rate at different conditions are decided by 1D flow numerical simulation of the oil circulatory and cooling system. Secondly, the flow passages of thrust-ring-pump are empirically designed under the restrictions of diameter and the speed of the thrust ring according to the head and flow rate from the simulation. Thirdly, the flow passage geometry matching optimization between thrust ring and oil bath is implemented by means of 3D flow simulation and performance prediction. Then, the pumps and the oil circulatory and cooling system are collaborative hydrodynamic optimized with predicted head-flow rate curve and the efficiency-flow rate curve of thrust-ring-pump. The presented methodology has been adopted by DFEM in design process of thrust-ring-pump and it shown can effectively improve the performance of whole system.