• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.10a
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• pp.27-35
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• 2004

In this paper a method for finding solution of acoustic, vortex and entropy wave-equations in a cylindrical tube with variable section area was suggested under the consideration of that the high frequency instability in a rocket engine combustion chamber is an acoustic phenomena, which is coupled with combustion reaction, and that a combustion chamber and exhaust nozzle are usually shaped cylindrically. As a consequence of that some method, which enable the quantitative analysis of the influence of entropy and vortex waves to acoustic wave, was suggested.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.288-293
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• 2006

The combustion performances and characteristics of the subscale liquid rocket combustion chamber are discussed in this paper. Subscale combustion chamber is composed of mixing head, ablative cooling cylinder, and water cooling nozzle. The mixing head has eighteen coaxial swirl injectors and one center coaxial swirl injector for ignition. The mixing heads employing the injectors of low different recess length are considered in this paper. The results of the firing test, comparison of performance, and characteristics of static and dynamic pressures of the four different mixing heads are described. The characteristics of combustion at design and of design points are also discussed.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.3
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• pp.60-66
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• 2006

Notable are the burning rate characteristics of solid propellant burning at extremely high pressure(10000-20000 psia). The burning rate test using closed bomb shows the discontinuous increment around 4000 psia so that the exponent of burning rate(n) is almost double, from 0.4 to 0.8. The pressure-increasing rate of the test motor is about 300 times as high as that of the motor operating at the conventional pressure, less than 2000 psia, is, therefor the burning rate is augmented about 5-50 times. The performance prediction reflecting the pressure-change-rate effect are fairly comparable with the test data at various test conditions.

• Journal of the KSME
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• v.28 no.5
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• pp.469-475
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• 1988

연료소비율의 향상은 점차 감소되어 가는 경향에 있다. 그 원인은 3원촉매변환기 채용에 의한 이론공기연료비의 사용, 기관의 연소개선이 발전하여 고압축비화에 의한 연료소비율 향상이 더 이상 어렵게 되었다는 점을 들 수 있다. 한편, 고압축비화의 역효과로는 연소실내 최고압력이 증가하여 각부의 강도나 기관 소음의 문제가 대두된다. 이들 역효과를 타파하여 충분한 연료 소비 향상을 얻을 수 있는 수단이 단기적인 과제가 될 것이다. 전자제어, 희박연소, 마찰저감 등 통상의 엔진의 개량에 대한 노력이 계속될 것이다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2004.10a
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• pp.241-245
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• 2004

• 보일러설비
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• s.2
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• pp.72-79
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• 1988

저온수 난방방식인 연탄용 온수온돌이 지난 `60년후반 민간연구가들에 의해 개발된 이래 실사용 열효율이 40$\%$ 미만인 점을 감안, 필자는 현장조사연구, 현장실험, 온수온돌 시공법 강의, 연탄연소기기에 관한 한국공업규격 등의 심의 과정에서 얻은 지식을 토대로 연탄연소의 기초이론, 연탄용 온수온돌의 시공방법, 온수온돌의 하자발생 원인 분석 및 그 대책을 제시하고자 한다.

• 보일러설비
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• s.3
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• pp.68-74
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• 1988

저온수 난방방식인 연탄용 온수온돌이 지난 `60년후반 민간연구가들에 의해 개발된 이래 실사용 열효율이 40$\%$ 미만인 점을 감안, 필자는 현장조사연구, 현장실험, 온수온돌 시공법 강의, 연탄연소기기에 관한 한국공업규격 등의 심의 과정에서 얻은 지식을 토대로 연탄연소의 기초이론, 연탄용 온수온돌의 시공방법, 온수온돌의 하자발생 원인 분석 및 그 대책을 제시하고자 한다.

• 전기의세계
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• v.39 no.11
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• pp.45-51
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• 1990

원자력발전이 화석연료를 연소하는 화력발전에 비하여 유리한 점은 연료비가 저렴하며, 핵연료 주기를 국산화함으로서 에너지 해외 의존도를 줄일 수 있다는 점이므로 국가 차원의 체계적인 핵연료 주기 기술자립계획의 수립과 적극적인 추진이 요구된다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.137-142
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• 2008

Ignition characteristics of combustion chamber with LOx lead cyclogram for liquid rocket engine were described. The combustion chamber has chamber pressure of 60 bar, propellant mass flow rate of 89 kg/s, and nozzle expansion of 12. Cold flow test to determine the filling time of propellant for cyclogram with LOx lead supply, ignition test to check the ability to ignite starting fuel from the ignitor, low pressure combustion test to check the propagation of flame into main fuel-oxidizer mixture from starting fuel and the main combustion stage, and design point combustion test to check the combustion performance were performed. Ignition and combustion tests with LOx lead supply were successfully performed and the stable cyclogram of start sequence for combustion chamber was developed.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.2
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• pp.1-8
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• 2013

This study presents relations between the time lag and interaction index of the impinging-jet injectors using the time lag model in a model chamber. The response of the flame is analyzed to artificial perturbation with 5% amplitude of oxidizer speed at a resonance frequency. At the mixing point of fuel and oxidizer, which determines the characteristic length, the relationship between velocity perturbation and heat release rate is quantified by combustion parameters of interaction index and time lag. In this method, time lag or delay is calculated by the characteristic length and the average velocity obtained from numerical results. The tendency that the time delay decreases with axial jet velocity has been observed.