• Journal of Aerospace System Engineering
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• v.11 no.3
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• pp.22-30
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• 2017

This paper examines a survey on recent research regarding health monitoring and management for liquid rocket engines (LRE). For this, we investigated precedent techniques applied to LRE development. Particularly, we focused on open-cycle LRE to apply to KSLV-II (Korea Space Launch Vehicle II). Through this study, we subdivided health monitoring algorithms and analyzed fault detection and diagnosis algorithm developed in China, since China researched open-cycle LRE that have the same cycle as KSLV-II rocket engines. We discuss significant points to be considered regarding development of the KSLV-II.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.5
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• pp.22-30
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• 2015

A gas generator which generates turbine driving gas by burning a part of propellants is used in an open cycle liquid rocket engine and as a main component of an open cycle liquid rocket engine autonomous hot firing tests are required to investigate the combustion performance and characteristics of the gas generator. However, since the combustion gas generated by a gas generator is choked at the turbine nozzle in the turbine manifold, it is necessary to consider the internal volume of turbine manifold as well as that of the gas generator for correct investigation of the combustion performance, characteristics, and acoustic characteristics of the gas generator. Therefore, in the paper hot firing test results of a gas generator with a turbine manifold simulator are described and characteristic prediction using the autonomous test of a gas generator is explained.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.2
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• pp.125-130
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• 2018

The technology development of a high performance upper stage engine for a GEO(GEostationary Orbit) KSLV(Korea Space Launch Vehicle) is undergoing in Korea Aerospace Research Institute. KSLV is composed of an open cycle engine with gas generator, which is for a low orbit launch vehicle. However the future GEO launch vehicle requires a high performance upper stage engine with a high specific impulse. The staged combustion cycle engine is necessary for this mission. In this paper, current progress and future plan for staged combustion cycle engine development is described.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.34-37
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• 2010

One dimensional transient analysis was studied for turbopump-fed liquid propellant rocket engine(LRE) system in starting using AMESim. The effects of timing of gas generator fuel valve opening and gas generator ignition to start-up stability were researched for open cycle type system using LOX/RP-1 to propellants. Result show that the parameters and sequence on start-up should be considered to design optimized turbopump-fed LRE system.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.3
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• pp.295-299
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• 2017

In this study, computer simulation and optimization works have been performed for an open-loop Rankine cycle to generate power using five cases of liquefied natural gas compositions. PRO/II with PROVISION V9.4 from Schneider electric company was used, and the Soave-Redlich-Kwong equation of the state model was utilized for the design of the power generation cycle. It was concluded that more power was obtained from less molecular weight liquefied natural gas since there was more volumetric flow rate with less molecular weight.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.21-24
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• 2010

The cooling channel of the preburner for staged combustion engines was studied. The combustion pressure of the researched preburner is about 210 bar which is very high compared with the engines of the Korean Launch Vechicle and 30 ton class liquid rocket engines developed as a pre-research program. Also, the combustion is an oxygen rich process unlike the gas generators of open cycle kerosene engines. Thus the cooling process is very important to make the preburner stable. Many configurations for the preburner were developed and numerically analyzed. As a result, the pressure loss could be reached below the target.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.3
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• pp.109-118
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• 2018

Korea Aerospace Research Institute has developed a staged combustion cycle rocket (SCCR) engine with high specific impulse to send a 3-ton class satellite into geostationary orbit while conducting a Korean Space Launch Vehicle (KSLV) II project. The SCCR engine is different from the KSLV-II engine, which is an open cycle engine using a gas-generator. The SCCR engine with a closed cycle engine is composed of a pre-burner, a turbo pump, and a main combustor. The technology demonstration model (TDM0) was assembled and tested in the 7ton-class engine combustion test facility of Naro Space Center, and the combustion test was successfully conducted.

• Journal of the Korean Institute of Gas
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• v.20 no.5
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• pp.50-56
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• 2016

In this work, the open-drive oil free air compressor is modified to activate an organic Rankine cycle system as an expanding machine. The shape of the modified scroll expander case is a rectangular parallelepiped and the size of the case is $0.0394m^3$. The scroll expander is operated in an ORC using R245fa as working fluid with various working conditions for the performance test. The test data points are used to calculate the parameters of the scroll expander semi-empirical simulation model. The simulation results are compared with the experimental results to validate the simulation model.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2017.11a
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• pp.1453-1469
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• 2017

우리나라는 후발주자임에도 불구하고 개방형 운영체제의 전격적 채택과 고급 기종 중심의 공격적 제품 라인 확대, 그리고 가치사슬의 수직 통합 체계 구축 등에 힘입어 2011년 세계 스마트폰 시장 점유율 1위를 차지하였다. 그러나 우리나라 스마트폰 산업은 시장 점유율 1위를 달성한지 4년만인 2015년 또 다른 후발주자인 중국에 추격을 허용하였다. 이와 같은 스마트폰 산업 주도권 이전 현상을 논의하기 위해 본 연구는 추격 사이클 이론에 기반하여 중국 스마트폰 산업의 추격과 관련한 기술 수요적 정책 및 제도적 기회의 창을 고찰하고, 이에 대한 중국의 전략적 대응과 우리나라의 실책을 논의하였다. 먼저 기술적 기회의 창으로 스마트폰 아키텍처의 모듈화와 시스템 반도체의 원칩화는 스마트폰 생산에 필요한 기술적 지식의 장벽을 낮추는데 기여하였다. 또한 2013년부터 급성장하기 시작한 저가(190달러 이하) 스마트폰 시장은 기술적 열위인 중국의 시장 개척에 우호적 기회로 작용하였다. 이와 함께 중국 정부의 스마트폰 관련 연구개발 투자 확대는 중국에게 우호적 사업 환경을 제공하는 정책적 기회의 창으로 작용하였다. 이와 같은 기회의 창을 활용하기 위해 중국 스마트폰 산업은 빠른 시장 진입, 원가 절감을 위한 현지 부품 채용, 정부 연구개발 투자를 활용한 기술 역량 축적 등의 전략적 대응을 전개하였다. 반면 우리나라는 고급 기종 생산 고수와 저가 기종 출시 지연, 수직통합 체계의 고착화에 따른 부품 경쟁력 악화에 따라 중국에 추격을 허용하게 되었다. 본 연구는 산업 주도권 이전 현상에 대한 최신 실증을 추가함으로써 추격 사이클 이론의 발전에 기여할 것으로 기대되며, 향후 우리나라 스마트폰 산업 발전 정책 발굴에 중요한 지침으로 활용될 것으로 기대된다.

• Journal of Aerospace System Engineering
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• v.11 no.5
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• pp.6-12
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• 2017

This paper deals with mathematical modeling of a 75-ton open-cycle Liquid Propellant Rocket Engine (LPRE) and the steady state simulation based on a nominal operating point. Each component of open-cycle LPRE may be classified into seven major categories using thermodynamics and dynamics characteristics. To simplify the simulation model of LPRE in this paper, we used four govern equations with assuming no heat transfer process. We confirmed the mathematical model of LPRE by using the error ratio and comparing the experiment data and simulation data in steady state, and checked the stability with the linearized model. Finally, we demonstrated the simulation model as compared to the transient response of experimental data.