• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.5
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• pp.60-67
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• 2015

The compressor is used for many fields not only in the industrial sector, but also as a general household product. The energy consumption required for the compressor operation is very large. The reciprocation compressor is widely used as an air compressor. Regarding the reciprocating air compressor, the discharge of the gas compacted by the method of compressing the gas by using the oscillation of the piston is generated by the piston reciprocation 1 church 1 number. When compressing after compressing the air by the oscillation of the piston, the marine reciprocating air compressor is the vibration generated in the compressor and surrounding structure due to the energy of the generated inertia. If the effect of these harmful elements can be reduced, it supports the service of the vessel. In addition, accidents generated by the noise of the vibration can be prevented. Therefore, in this research, firstly, the structural analysis of the piston part was performed, the safety factor in all results was drawn based upon this, and the reliability of the interpretation was examined in order to create the optimal design for the air compressor.

• Transactions of the Korean Society of Mechanical Engineers
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• v.9 no.6
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• pp.810-820
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• 1985

배기 decoupling chamber룰 갖고 있는 맥동 연소 급수가열기에 대한 수학적인 모델링과 관련된 컴퓨터 시뮬레이션을 하였고, 이 때 계에 대한 맥동 현상과 관련된 열적 및 동적 특성을 고려 였다. 시뮬레이션결과 시동기간에 대한 계의 각 부분에서 일어나는 열전달, 압력 및 온도를 구 였고 또한 해석의 제한성과 개선의 필요성을 논의하였다. 이 연구에서 얻어진 결과는 도관에서 맥동에 의한 대류열전달을 예측하기 위한 모델을 세우는데 활용될 수 있다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.339-343
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• 2006

Model SCRamjet Engine intake is designed for Ground test. The designed Intake provides hot and slow flow with the combustor. Flow separation is controlled by the shock wave segregation based on the Korekegi criteria. With Kantrowitz limit analysis, side wall cut out region is also set for the self start.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.662-667
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• 2000

A simulation procedure for a full transient analysis of the start-up of heavy-duty gas turbines for power generation is constructed. Compressor stages are grouped into three categories (front, mid, rear) and three different stage characteristic curves are applied to consider the different low-speed operating characteristics. Start-up behavior of a typical single-shaft gas turbine for power generation is simulated. The predicted transient behavior shows a good agreement with the field data. Special attention is paid to the effects of the modulation of VIGV on start-up characteristics, which play a key role in the stable operation of gas turbines.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.268-271
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• 2010

Hypersonic engine test facility with ejector system was tested. Ejector system was designed by revised EJSIMP code. The performance of the ejector system was predicted by numerical analysis. As a result, ejector system satisfied the facility design requirement. Based on the pressure level, the facility was successfully started at Mach 3.5 and 20km altitude condition.

• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.1
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• pp.56-64
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• 2010

A system design has been conducted of the liquid rocket engine for Korean launch vehicle (KSLV-II, Korea Space Launch Vehicle II). The present turbopump-fed liquid rocket engine of vacuum thrust 76 ton and vacuum specific impulse 297 sec adopts gas generator cycle. The combustion pressure of the regeneratively cooled combustor is 60 bar. The propellant is LOx/kerosene. The engine is started by pyrostarter and the combustor is ignited by TEA (TriEthylAluminium). The engine system performance and the subsystems performance requirements are given through energy balance analysis. The combustion pressure, specific impulse and the engine mass are analyzed to be reasonable comparing with the published data. The startup analysis method which will be used in the future has been validated against the turbopump-gas generator coupled test. The tuning method for performance variation of the engine which is not actively controled has been prepared by mode analysis and performance deviation analysis.

• Aerospace Engineering and Technology
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• v.13 no.1
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• pp.70-75
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• 2014

Programs of energy balance, mode analysis and transient analysis for a liquid rocket engine have been introduced. The analysis methods have been verified through comparison between the present results, and the results of the other program and experimental data. An energy balance analysis is used for engine system design at the early development phase. A mode analysis is used for decision of engine operation conditions and test conditions, and studying deviation of an engine performance. A transient analysis can predict a propellant flow rate, thrust, impulse at transient phase. It is essential to establish a startup/shut down sequence. The analysis programs will be used to develop the engines of KSLV-II.

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.4
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• pp.48-55
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• 2008

In this paper, numerical analysis of the surface gas temperature on turbine blades has been performed to investigate the temperature profiles characteristics of a partial admission supersonic turbine driven by high temperature and pressure gas of pyro-starter with two different types of turbine blade edge shape. In order to examine the surface gas temperature on turbine blades at initial starting, computations tlave been carried out at several turbine rotational speeds in the range of $0{\sim}10,000$ rpm for each type of turbine edge shape. "Sharp" edge and "Round" edge types were taken as the turbine edge shape factor. As turbine rotational speed increased, the average temperature of turbine blades was further decreased. It was also found that the surface temperature of turbine blades with a sharp edge was lower than round-type edge turbine blades.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.115-118
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• 2001

본 논문에서는 역률 개선용 제어 IC를 사용하여 고압나트륨램프의 역률을 개선시킨 전자석 안정기를 제안하였다. 또한 인버터 회로를 설계하여 시동전압의 과도특성을 해석하였으며, 전원측에 EMI 필터를 설계하여 전자식 안정기 시스템을 보호하였다. 자기식 안정기와 전자식 안정기에 대한 역률, THD 및 광속 등의 전기적 특성을 비교 측정하였다. 제안된 고압나트륨램프용 전자식 안정기의 출력을 측정한 결과 역률은 99.9[%], THD는 4.51[%]로 나타났다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.631-645
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• 2002

●정의 정척레일을 연속 용접하여 1개의 레일길이를 200m 이상으로 부설한 레일 ●장대레일화 - 차량 시동/제동하중에 의한 교축방향 수평력 작용 - 기존 : 수평력 배분을 위해 단순교로 시공(레일 이음매) - 현재 : 장대레일화 ● 장점 -유지보수비 절감 -승차감 향상(충격/소음 저감) -고속화 및 운행 안전성 향상 ●단점 -큰 레일 축력(파단/좌굴) -교량부, 급곡선부, 분기부 - 장대레일 종하중(하부구조) (중략)