• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2423-2428
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• 2008

A turbo classifier having a rotating rotor of two stage classification region has been developed to have a cut size of 1 micro meter. Particle number concentrations were counted using Aerosol Particle Sizer (APS, TSI co., USA) at inlet and outlet of the classifier. Partial classification efficiency was obtained at various rotation speeds, total flow rates, and feed rates of powders, and classification characteristic depending on design parameters was discussed. Classification performance was enhanced as rotation speed of rotor increased and total flow rate decreased.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.451-456
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• 2003

In this study, the overall performance and the effect of the tip leakage flow of the centrifugal compressor with the refrigerant HFC-l34a were numerically studied using CFX-TASCflow. To study the effect of a tip leakage flow, the numerical study of the overall performance of HFC-l34a centrifugal compressor with a cascade diffuser was preceded and compared with experimental result. Six different tip clearances were used to consider the influence of a tip clearance on performance. The tip leakage flow was illustrated for qualitative discussion. The results obtained in this study can be applied to the determination of the cold clearance.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.324-329
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• 2003

Asynchronus high speed turbo blower of 100HP class with gas bearing supports is developed. The high speed motor is cooled by air and it's RPM is controlled by high frequency inverter to adjust inlet flow rate. Product family is ranged from 50 to 200HP and covered by three frames. Highly efficient impeller is designed and proved by performance test on system. Overall measured system efficiency is 82% including motor and inverter. The motor efficiency is about 95%. It is designed to guarantee to operate at ambient temperature of 35 Deg.C and max 45 DegC. Gas bearing with high load capacity is developed to support heavy rotor on low rotational speed.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.340-345
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• 2003

Cryogenic turbopump test facility(CTTF) is designed and developed. Hydraulic and cavitation performance of turbopump in cryogenic environment can be measured. Working fluid is liquid nitrogen and operating temperature is $-197^{\circ}C$. Liquid nitrogen run tank, catch tank and pressurizing tank has been built and remote tank pressure control system are installed. Maximum power of turbopump is 320kW and its maximum speed is 32000rpm. Cryogenic fluids and lubricating systems are effectively separated that long test times are acquired. Therefore hydraulic and cavitation performance can be measured accurately and effectively. This facility will contribute greatly to the development of turbopump for KSLV.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.323-323
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• 2003

Many recent development activities suggest the possibility of a high-speed turbo(centrifugal) compressor or blower for the industrial application of compressed air supplying system when used with the most advanced high-speed motor, inverter technology, and advanced bearing for high rotational speed. The problems to be overcome are of reliability, the application of mass production methods, cost effective manufacture and competitive running costs. This presentation is not focused on a specific technology advances but on an overall review of our recent experiences while we have developed the high pressure turbo blower for the commercial purpose.

• 한국유체기계학회 논문집
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• 제14권4호
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• pp.12-18
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• 2011

Volute casings for liquid rocket turbopump are designed and evaluated in a structural point of view. At the design step 3D modeling and finite element analyses are conducted iteratively. During the step various loads such as internal pressure, casing stiffness and mounting forces are considered in the analyses, along with the weight minimization effort. After the design step volute casings are manufactured by metal casting process, and then they are subjected to burst test for structural verification. In the burst test strains at several points are measured and compared with predicted values.

• 한국유체기계학회 논문집
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• 제12권2호
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• pp.52-57
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• 2009

The effects of number of blades on the hydraulic performance of the inducer were studied using a computational method. Inducers with number of blades from 2 to 4 were used for computations and the hydraulic performances of the inducers were compared. The computational results showed that the hydraulic performance decreased due to the increase of the skin friction loss at blade passages as the blade number increased. The results also showed that the strength of the backflow became weak because of the decrease of unfavorable pressure gradient as the blade number increased.

• 한국유체기계학회 논문집
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• 제13권4호
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• pp.5-10
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• 2010

This study is concerned with effects of impeller blade thickness on performance of a turbo blower. This turbo blower is developed as an air supply system in 250 kW MCFC system. The turbo blower consists of an impeller, two vaneless diffusers, a vaned diffuser and a volute. The three dimensional, steady state numerical analysis is simultaneously conducted for the impeller, diffuser and volute to investigate the performance of total system. To consider the non-uniform condition in volute inlet due to volute tongue, full diffuser passages are included in the calculation. The results of numerical analysis are validated with experimental results of thin blade thickness. Total pressure ratio, efficiency, slip factor and blade loading are compared in two cases. The slip factor is different in two cases and the comparison of two cases shows a good performance in thin blade thickness in all aspects.

• 자동차안전학회지
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• 제8권2호
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• pp.24-29
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• 2016

A small-sized turbocharger is generally used in downsizing engine for various vehicles. When a centrifugal compressor, which is one of the crucial units of the turbocharger, is downsized, the compressor has much more possibilities of being damaged because of its high rotating speed, causing insecure structural soundness. Thus, it is of essential to study on the improvement of the structural soundness of a small-sized turbocharger. In this study, numerical analysis on the various blade geometries and mass flow rate of the compressor was performed using the commercial software ANSYS CFX. In addition, the evaluation on the structural soundness of a compressor impeller for respective cases was conducted using ANSYS Mechanical. As a result, it was shown that the compressor had higher efficiency with increasingly secured structural soundness.

• 항공우주기술
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• 제5권2호
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• pp.174-180
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• 2006

액체로켓엔진에서 연료와 산화제를 가압하는 역할을 하는 핵심부품인 터보펌프는 극저온 산화제와 구동 터빈의 고온 환경이 동일 축에 분포하고 있으며 내부 회전부 간극이 매우 작고 회전속도가 높아 기계적으로 대단히 열악한 환경에서 동작한다. 따라서 사고 위험도를 낮추기 위한 구조 해석 및 시험이 필수적인데, 본 연구에서는 특히 터보펌프 케이징의 구조해석 및 응력 측정이 이루어졌다. 기존의 단품 레벨에서의 해석에서 벗어나 연료펌프와 산화제펌프의 케이징 조립체 레벨에서 내압기밀시험 조건에 대한 구조해석이 이루어졌으며 이를 통하여 케이징 간 체결효과 및 실 부분의 접촉 압력을 성공적으로 고려할 수 있었다. 또한, 연료펌프 케이징에 나타나는 높은 수준의 응력 집중 현상을 해석과 측정을 병행함으로써 성공적으로 예측하였다.