• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.125-130
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• 2003

본 논문에서는 액체로켓엔진에서 터보펌프의 160kW급 터빈을 구동하고, 액체산소와 케로신을 추진제로 사용하는 가스발생기의 설계점 연소성능시험 결과에 대해 논의하였다. 충돌형 F-O-F 인젝터, 물냉각 채널을 가진 연소실, torch ignitor, turbulence ring 그리고 측정 링을 갖는 가스발생기에 대해 기술하였고, 점화, 연소, 종료 등의 시험 cyclogram에 대해 언급하였다. 설계점에서의 연소시험 및 turbulence ring 장착여부, 연소실 길이 변화에 따른 연소시험의 결과들에 대해 기술하였다. 연소시험 결과 가스발생기는 설계점에서 안정된 작동성을 보여주었고, 연소압력 및 온도 등의 성능이 예측치에 근접하는 결과를 보여 주었다. Turbulence ring은 출구에서의 가스온도를 균일하게 분포시켜 효과적인 혼합 장치임을 보여 주었고, 4-6msec 정도에서의 잔류시간에서는 연소효율의 차이가 크지 않음을 알 수 있었다. 가스발생기 출구에서의 온도는 공급되는 추진제의 O/F ratio에 따라 매우 민감하게 반응함을 알 수 있었다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.3
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• pp.114-119
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• 2004

An oxyge generator, which is applied to a particular space such as automobile, must consider compactness and lightweight as well as problems caused by noise, vibration and heat dissipation. For these matters, a BLDC motor was adopted to reduce heat while a bed using synthetic zeolite NaX made it possible to generate high-density oxygen with relatively small size. Moreover, owing to the characteristic of synthetic zeolite Nax, a two-head vacuum pump was designed to desorb nitrogen without additional pump unit.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.1
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• pp.68-76
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• 2022

Upper stage of the Korea Space Launch Vehicle-II(KSLV-II) uses a 7-tons class liquid rocket engine and is an open gas generator cycle with a turbopump supply method that uses kerosene/liquid oxygen as the propellant combination. This study first provided a brief overview of the design and development process of the upper stage engine. In addition, it introduced the solutions and results applied to some of the problems that occurred during the development process of the upper stage engine.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.356-359
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• 2003

선박이 배출하는 안정수(ballast water)는 외부로부터 유해 생물들이 유입되어 전파해 오는 주요경로로써, 해양환경 변화를 초래하는 매우 중요하고 위험한 일중의 하나이다. 그러나 이에 대한 효과적인 처리방법은 아직까지도 미흡한 상태이다. 선박 안정수에 포함되어 타 지역으로부터 옮겨지는 외래침입생물 처리 방안의 하나로, 강 전리방전 기술을 적용하여 고 밀집 산소와 물분자로부터 고농도 수산자유기(OH: hydroxyl radical)를 전리, 발생시켜서 활성입자를 신속히 확산시켜 비교적 낮은 수산기농도 하에서 유해성침입생물을 소멸 처리하는 환경 친화적 녹색 청정처리방법을 제안하였다. 제안된 기술은 대상물의 처리 후 부수적으로 발생할 수 있는 처리잔류물이 전혀 발생하지 않으며, 인공적 화학성분의 약제를 사용하지 않는 저렴한 처리방법이므로 대ㆍ소형 원양선박의 안정수에 들어있는 외래침입생물의 타 지역 해양확산을 안전하게 처리할 수 있는 자연치유적 신기술이다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.79-82
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• 2011

An afterburning device was developed to safely treat unburnt gases of fuel-rich condition discharged by a gas generator. Hot-firing tests for a subscale gas generator were carried out to investigate operation and safety of the afterburning device. When supplying additional liquid oxygen, the length of the afterburning flame was significantly reduced.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.196-200
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• 2006

This paper describes the current development status of the major subsystems, turbopump and gas generator, for a turbopump-fed liquid oxygen-kerosene rocket engine system. As a secondary stage of the liquid rocket engine development test, turbopump-gas generator powerpack tests are planned. The schematics of the test hardware and the test facility for the TP+GG coupled test are presented. The results of a preliminary analysis for operating regimes of the TP+GG coupled test are also presented.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.150-153
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• 2006

Gas generator should be adopted either fuel rich or oxidizer rich combustion because of the temperature restriction to avoid any possible thermal damages to turbine blade. This study focuses to model the non-equilibrium chemical reaction of kerosene/LOx with detailed kinetics developed by Dagaut using Perfectly stirred reactor(PSR) assumption. To predict more reliable species fraction and other gas properties, Frenklach's soot model was added to Dagaut's detailed kinetics.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.119-122
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• 2007

The present study employs experimental approach to identify combustion stability characteristics of fuel-rich gas generators. The gas generator of interest, fueled by LOx and Jet A-1, experienced combustion instability coupled to a longitudinal resonant mode of the combustion chamber at about 1200 Hz. The occurrence of instability is strongly associated with acoustic boundary condition at the exit .and axial location of maximum heat release. As a result, stretching heat release zone in the axial direction by increase of the fuel nozzle diameter has dramatically stabilized combustion.

• Development and Reproduction
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• v.4 no.2
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• pp.203-213
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• 2000

To investigate the effects of reactive oxygen species (ROS) on capacitation, acrosome reaction in human spermatozoa. Human spermatozoa were incubated with xanthine-xanthine oxidase (X-XO), $H_2O$$_2$, sodium nitroprusside (SNP) or lymphocyte. Otherwise, spermatozoa were incubated under low $O_2$ (5 ％) condition. Chlortetracycline (CTC) staining was conducted to assess capacitation and acrosome reaction. Analysis of lipid peroxidation was done by spectrophotometric determination of malondialdehyde (MDA) production in spermatozoa. $H_2O$$_2$, X-XO, SNP and lymphocyte treatment significantly increased capacitated spermatozoa within 1 h of incubation. There was no significant difference in capacitation between low- and high $O_2$ groups. In the presence of low concentration of $H_2O$$_2$, lipid peroxidation decreased significantly. However, under the high concentration of $H_2O$$_2$, lipid peroxidation significantly increased at the end of incubation compared to control. In the presence of high concentration of lymphocytes, lipid peroxidation significantly increased compared to control at 1hr of incubation. There was no significant difference in lipid peroxidation according to $O_2$ concentration examined. Acrosome reaction (AR) was evaluated by CTC staining after the progesterone challenge. In all ROS groups, AR increased compared to control. The X(100 $\mu$M) - XO (100mIU) system was the most potent to induce AR. Taken together, it suggested positive control of AR by ROS and the positive relationship between the lipid peroxidation and AR. The early onset of capacitation in the presence of ROS suggest that ROS might be a positive regulator of sperm capacitation and hyperactivation.

• 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.