• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.4
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• pp.50-60
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• 2014

Many countries are paying efforts to the research and development of water-breathing ramjet propulsion for submersible vehicle with the super-cavitation which makes traveling at high speed in underwater possible. In this study, a conceptual design of an underwater vehicle with water-breathing ramjet was carried out. Mission profiles and operating conditions are determined by examining the operation environment. Drag is estimated based on the theories of super-cavitation and fluid mechanics. The sizing and performance analysis of the components were performed using thrust required, thrust and specific impulse of designed engine were verified.

• Aerospace Engineering and Technology
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• v.2 no.2
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• pp.157-166
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• 2003

IPPT(Integrated Propulsion Performance Test)s were carried out as a final stage of KSR-III(Korea Sounding Rocket-III) propulsion system development three kinds of engine with different injector faceplate were tested, therefore a engine with composite baffle was certified for a KSR-III launcher. Though a engine with STS baffle which was designed for verification of combustion instability suppression ability was not final design, due to the combustion tests with this engine, it can be described that baffle has capability to suppress combustion instability at ignition and at mainstage in the case of KSR-III combustor.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.555-560
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• 1996

막대한 연구재원이 소요되는 원자력 개발분야에서 세계 초일류수준을 유지하고 있는 선진 원자력 연구개발사업기관들은 하나같이 종래에 도입한 "원자력 품질보증체제"를 확대시켜 "품질 무한경쟁시대"에 부응하는 "종합적 품질경영체제"를 도입하고 있다. 본 연구에서는 효율적인 연구소 경쟁력제고 방안도출을 위한 노력의 일환으로 현재 Total Quality Management(TQM) 체제를 도입하고 있는 해외의 ORNL(Oak Ridge National Laboratory), AECL(Atomic Energy of Canada Limited), ABB CE(Asea Brown Boveri Combustion Engineering), DNA(Defense Nuclear Agency)등을 방문한 결과를 토대로 연구소적 TQM체제 성공과 실패의 원인을 분석하여 도입당시의 추진조직, 추진전략, 추진효과에 대해 체계적으로 비교 분석하여 한국정서에 부합된 연구소적 성공 TQM체제 모델을 도출코져 시도하였다. 분석결과 이들 기관들은 TQM 추진을 위하여 먼저 단계별로 단기, 중기, 장기 계획을 수립하고, TQM 실무위원회를 구성하여, 최고경영자가 직접지휘하는 Top-down 방식의 TQM 추진으로 품질문제를 사전에 예방하고 있었다. TQM 도입 초기 실무부서로 부터의 적잖은 저항과 애로사항이 도출되어 많은 시행착오를 거쳤으며 지금은 TQM 정착단계에 있었다. 이러한 과정에서 원자력 선진기관들은 전사적인 TQM 교육을 통해 철저한 TQM 마인드를 고취시켰고 전 부서의 업무가 전사적 TQM 차원에서 수행되었다. 우리나라 원자력기관에서의 바람직한 TQM 도입 모델로서 첫째, 전직원 대상 TQM 교육실시를 통한 TQM 인식고취, 둘째, TQM 성공체제로서 "경영품질"에 초점을 맞춘 관리시스템 확보, 셋째, 동서문화 차이를 고려한 Bottom-up '||'&'||' Top-down 혼합방식을 제시하였다.ottom-up & Top-down 혼합방식을 제시하였다.

• Journal of the Korean Society of Propulsion Engineers
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• v.27 no.1
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• pp.49-57
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• 2023

The autogenous pressurization has been widely adopted for propulsion systems of next-generation reusable rockets due to its low cost and high reliability. The autogenous pressurization has a simple structure, but an understanding of the heat and mass transfer occurring inside the tank is essential. For this reason, a simulation test of the autogenous pressurization was conceived. The experiment equipment was constructed based on overseas pressurization test facilities cases and expert advice. Unlike the actual autogenous pressurization system, the propellant tank was insulated to exclude external influences. The pressurized gas supply line and the propellant pipe were separated. Using the manufactured autogenous pressure experiment equipment, it is possible to evaluate the condensation phenomenon of pressurants in cryogenic propellants, comparison of the efficiency of pressurization using helium and evaporated gas and the pressurization capacity according to the temperature of pressurant.

• Journal of the Korean Society of Propulsion Engineers
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• v.4 no.3
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• pp.19-28
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• 2000

In general the data such as thrust, pressure, temperature and combustion time are measured in developing the propulsion system of solid rocket motor through static firing test. But in the case of personal surface to air missile there are required a severe safety specifications in order to eliminate gunner hazard from the exhaust plume of motors. The safety requirements lead to the design of separation device and safety igniter device. The dynamic firing test for the designed two devices should be conducted under the flight environmental conditions to verify the requirements compliance. In this study the technique for dynamic firing test of propulsion system of personal surface to air missile is proposed and the method to design the dynamic test bench is also studied.

• Journal of the Korean Society of Propulsion Engineers
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• v.6 no.4
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• pp.47-58
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• 2002

The pressure regulator has been developed as a pressure-control device of propellant tank in KSR-III. The pressurization system of KSR-III is a basic pressurization system composed of pressurant, He tank and propellant tank. The pressure-control regulator is the most important part of gas-pressurized feed system along with He tank, pyrovalve and He fill valve. The first model of the regulator is tested to satisfy in leakage, strength and basic performance. The second model is tested in the overall test of the KSR-III propulsion system using water. From the test result of the second model, we conclude that the capacity of valve(Cv) must be increased in real system. The third model is modified and tested in the overall test of KSR-III propulsion system using propellant. Finally, the pressure-control regulator is qualified from firing test.

• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.5
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• pp.61-70
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• 2017

Robust thrust distribution method of solid DACS is researched. For the case of the system which has higher number of actuation nozzles than the degree of freedom of thrust to be controlled, the robust thrust allocation law which accommodate the abnormal operation is suggested. Assuming the situation that some nozzles are uncontrollable, the error between nozzle throat area command and response can be calculated. The error is used for realtime reshaping of weighting matrix. From the weighting effect, the nozzle which operated abnormally has low responsibility for the command then, the thrust error is reduced. The suggested algorithm is verified by the simulation of abnormal operation condition of DCS and ACS nozzle respectively.

• The Journal of the Korea Contents Association
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• v.9 no.7
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• pp.315-324
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• 2009

Public institutions guaranteed exclusive position of core business are likely to be inefficient in management. Past governments made various efforts to innovate public institutions. Participatory government drove innovation of public institutions through Ministry of Planning and Budget, and this innovation policy had problems as followings: shortage of common sense of innovation, lack of understanding of innovation, gradual execution of innovation instead of system innovation for business innovation, lack of consideration of characteristics of various public innovation, overlapping of evaluation system, and nonobjective design of evaluation indicator. MB government has diverse assignments for improvement of these problems as followings: transformation of business mind, voluntary participation of employee, improvement of management system of public institutions, reform of business evaluation system, promotion of internal competition, and construction of performance based business system. What is the most important point for successful reform of public institution is to achieve the support of general public with effective action plan and substantial programs.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.4
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• pp.1-10
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• 2006

In this paper, a calculation method of the thermodynamic parameters of cryogenic propellant is proposed when a cryogenic propellant tank is pressurized by gaseous helium(GHe) bubbling. Temperature of cryogenic propellant and mass of dissolved GHe into propellant were analyzed at the various operation of pressurization of tile liquid oxygen(LOX) and hydrogen($LH_2$) tank using helium bubbling. It was evaluated how the GHe bubbling influences to the thermodynamic parameters of LOX and $LH_2$ with results of the analysis. With the proposed calculation method, It will be able to confirm the feasibility of GHe bubbling as a pressurization system of cryogenic propellant tank and to optimize the pressurization system using GHe bubbling.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.676-677
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• 2010

In Naro Space Center, Naro launch vehicle launched 2 times. Launch pad for Naro launch vehicle in Naro space center equipped propellant feeding facility for operating launch process. This paper studied development process and operating method for liquid oxygen filling system of cryogenic propellant systems in launch pad propellant feeding facility.