• 한국산학기술학회논문지
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• 제13권4호
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• pp.1503-1510
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• 2012

본 연구는 HVAC 시스템의 성능 개선을 위해 원심 임펠러의 블레이드의 중심각, 토출구의 길이와 같은 형상을 변화시켜 수치적으로 해석하였다. 임펠러 내의 속도장, 압력장, 난류 강도, 온도장을 계산하기 위하여 상용 CFD 코드인 FLUENT를 사용하였다. 시스템의 워밍업에 상관없이 히터 파워 레벨이 증가하면 임펠러 내 주위의 온도는 외기 투입시 온도가 증가하였지만 내기 순환 시에는 온도가 오히려 감소하였다. 결과적으로 성능 개선을 통한 $CO_2$ 감소는 블레이드 중심각 및 토출구 길이의 변화를 통한 유속 및 유량의 변화를 통해 이룰 수 있었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1776-1779
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• 2003

This research presents Reverse Engineering of a Impeller. The modeling introduced in this paper adopts polynomial regression that is utilizing approximating technique. The measured data are obtained from measuring with Coordinate Measuring Machine. This paper introduces efficient methods of Reverse Engineering using Polynomial Regression.

• 한국해양환경ㆍ에너지학회지
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• 제13권2호
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• pp.105-111
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• 2010

조류발전용 HAT 임펠러 설계에 대한 성능 비교 연구를 통하여 설계 개선방향에 대하여 고찰해 보았다. 기존의 조류발전용 임펠러는 풍력에서 사용하고 있는 설계 개념을 그대로 사용하는 경향이 있으며 밀도 차이가 크고 풍력과는 다른 조류발전의 특성을 고려하여 새로이 설계된 임펠러와 기존의 임펠러를 비교하였다. 향후 계산에 의한 비교 뿐 아니라 실험 그리고 경사류등과 같은 특수한 경우에 대한 검증을 수행할 계획이다.

• 한국유체기계학회 논문집
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• 제15권3호
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• pp.64-69
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• 2012

Generally the Shrouded type impeller is considered to free from the loss of tip leakage flow, but it is actually not possible to complete sealing between the rotating impeller and the sealing which is stay still. As a result, there is the possibility of flow leaking between impeller exit to entrance, especially with high pressure ratio compressor machine. The Cavity leakage flow is expected to influence negative effect on a machine performance and also inner flow structure. In this study, Impeller with shroud-casing gap leakage flow is simulated by numerical method (Using CFX 12.1). The influence of leakage flow on compressor performance and efficiency will be analysed, also detail flowfield change will posted.

• 한국유체기계학회 논문집
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• 제15권3호
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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.

• 대한기계학회논문집A
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• 제22권1호
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• pp.102-110
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• 1998

The analysis of lateral hydrodynamic forces in the leakage path between a shrouded pump impeller through wear-ring seal and its housing is presented. Governing equations are derived based on Bulk-flow and Hirs' turbulent lubrication model. By using a perturbation analysis and a numerical integration method, governing equations are solved to yield leakage and rotordynamic coefficients of force developed by the impeller shroud and wear-ring seal. The variation of rotordynamic coefficients of pump impeller shroud and wear-ring seal is analyzed as parameters of rotor speed, pressure difference, shroud clearance, wear-ring seal clearance, and circumferential velocity at the entrance of impeller shroud for a typical multi-stage centrifugal pump.

• 한국유체기계학회 논문집
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• 제3권1호
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• pp.10-18
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• 2000

This paper reports the impeller performance of centrifugal pump, modified HES65-250. Developed CFD code uses SIMPLE algorithm, power-law scheme, standard $k-{\espilon}$ turbulence model in curvilinear coordinate system. The calculations are conducted for 5 cases, from 0.6 to 1.4 of flow rate ratio with 0.2 increment. The flow characteristics inside of impeller are analysed. The results show that reversal flows exist at the inlet of impeller which have small rotary stagnation pressure. The obtained results are compared with the experimental data at impeller exit and shows good qualitative agreement.

• 한국기계가공학회지
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• 제10권4호
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• pp.109-114
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• 2011

An impeller is difficult to machine because of severe collision due to the complex shape, overlapping and twisted shape that form impeller blades. So, most CAM software companies have developed CAM module for manufacturing impeller in addition to their CAM software. But it is not still easy for inexperienced users to machine impellers. The purpose of this paper is the development of automatic CAM module for manufacturing impeller(E-ICAM) which is based on visual basic language and it is used CATIA graphical environment in order to be easily machining impellers. Automatic CAM module for manufacturing of impellers generates tool path, and proposes recommended cutting condition according to the material of stock and tool. In addition, it has also included a post processor for 5-axis control machining. Therefore the user can easily machine impellers using this automation module.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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• pp.405-410
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• 2004

2-dimensional impeller's distinctive feature is expected to have an influence on performance and flow characteristics of centrifugal compressor. And new design method is required for 2-dimensional impeller, because the unique geometry cannot be designed using conventional theories. The objective of this study is to advance new design technology for 2-dimensional impeller and to investigate the performance characteristics of designed 2-dimensional centrifugal compressor. The performance test for 2-dimensional impeller is conducted at 35000, 40000 and 45000rpm. Also numerical calculation is applied by using commercial CFD code, FLUENT, and the results are compared with experimental results.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 1999년도 유체기계 연구개발 발표회 논문집
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• pp.170-178
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• 1999

In general, an impeller of centrifugal turbomachinery is designed at isolated condition without considering the presence of a volute, but when the impeller is operating with its volute, the performance of impeller can be different. This is largely caused by the interaction between the impeller and volute flow fields. The magnitude of distortion is increased as the operating point is away from the design point and, as a result, the interaction between the impeller and volute is stronger. In the present calculation, the flow through the impeller is simulated using coarse grids. The flow within the impeller and the volute is naturally unsteady, but the flow is assumed to be steady across the interface between the volute and impeller flow fields. Under the assumption of steady three-dimensional incompressible turbulent flow, the time averaged N-S equations involving standard k-$\epsilon$ turbulent model was solved by the F.V.M. The calculation results are compared with the experimental results obtained for an industrial fan by Sakai etc. and the Hood agreement is demonstrated. And the effects of the impeller-volute interaction are studied.