• 한국추진공학회지
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• 제23권3호
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• pp.1-8
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• 2019

아산화질소($N_2O$) 열분해를 위해 아크 플라즈마를 이용한 점화 실험을 수행하였다. 기존의 점화기들은 신뢰성 및 즉각적인 응답을 얻기 어렵다는 단점을 해결하기 위한 방안으로 플라즈마를 활용하는 방안을 제시하고자 하며, 점화기로써의 가능성을 보기 위해 가스 온도 측정 및 연소 실험을 수행하였다. 1 g/s, 0.7 A 조건에서 가장 안정적인 방전 특성을 보였으며 이때 측정된 벽면 부근의 온도는 약 $960^{\circ}C$이었다. 이를 바탕으로 하이브리드 로켓 연소 실험을 수행하였다. 플라즈마 방전 이후 약 3.1 sec만에 총 유량 10 g/s의 메인 연소가 성공적으로 이루어졌으며 점화에 필요한 플라즈마 발생을 위한 에너지 소모량은 1,780 J이었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2003년도 제21회 추계학술대회 논문집
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• pp.173-178
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• 2003

슬링거 연소기의 연소특성을 파악하기 위한 연구를 수행하였다. 연료는 고속으로 회전하는 축의 연료노즐을 통하여 연소기내로 분사된다. 회전분무시스템의 분무특성을 파악하기 위하여 PDPA를 이용하여 연료노즐의 회전속도 변화에 따른 분무입자의 크기를 측정하였다. 연구결과 분무액적의 크기는 연료노즐의 회전수와 직접적인 상관관계가 있음을 알 수 있었다. 실물크기의 연소기를 제작하여 한국 항공우주연구원의 연소시험설비에서 점화 및 연소시험을 수행하였다. 시험결과 점화성능 및 연소효율은 연료노즐 회전수에 따라 증가하는 경향을 나타내고 있었으며, 연소기출구온도는 매우 균일한 온도분포를 나타내었다.

• 한국추진공학회지
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• 제24권2호
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• pp.43-51
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• 2020

고폭화약을 이용한 격벽형 착화기를 가속노화 후 성능시험을 수행하여 노화특성을 확인하였다. 격벽형 착화기는 마이크로 착화기에서 발생한 충격파가 격벽을 통해 엑셉터 화약과 점화 화약에 전달되어 동작한다. 제품에 대한 수명평가를 위해 수명연한에 따른 가속노화 조건을 설정하고, 매 주기마다 시료에 대한 점화 성능을 10cc 밀폐용기 시험을 통해 작동지연시간과 최대압력을 측정하여 요구규격 만족여부를 확인하였고, 분산분석을 통해 노화여부를 판단하였다.

• 한국화재조사학회지
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• 제11권1호
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• pp.63-73
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• 2007

페놀수지로 몰딩된 바이메탈식 서모스탯의 반복적인 동작에 의한 발화위험성을 검토하기 위하여 발화된 것으로 판정된 사례의 연구와 동작 횟수를 가속시킨 실험을 행하였다. 사례연구 및 실험결과, 페놀수지로 몰딩된 바이메탈식 서모스탯(이하 '바이메탈식 서모스탯'이라 칭함)은 반복적인 동작에 의하여 내측의 고정접점과 가동접점 부분 사이에서 몰딩재료인 페놀수지가 국부적으로 탄화되는 트래킹 현상이 발생되며, 이로 인한 전기적인 발열 및 용융 등에 의하여 내측으로부터 발화될 수 있다는 사실을 입증하였다.

• 대한기계학회논문집B
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• 제26권12호
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• pp.1639-1645
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• 2002

Micro engine that includes Micro scale combustor is fabricated. Design target was focused on the observation of combustion driven actuation in MEMS scale. Combustor design parameters are somewhat less than the size recommended by feasibility test. The engine structure is fabricated by isotropic etching of the photosensitive glass wafers. Electrode formed by electroplating of the Nickel. Photosensitive glass can be etched isotropically with almost vertical angle. Bonding and assembly of structured photosensitive glass wafer form the engine. Combustor size was determined to be 1 mm scale. Movable piston is engraved inside the wafer. Ignition was done by nickel spark plug which was electroplated with thickness of 40 ${\mu}{\textrm}{m}$. The wafers were bonded by epoxy that resists high temperature. In firing test due to the bonding method and design tolerance pressure buildup by reaction was not confirmed. But ignition, flame propagation and actuation of micro structure from the reaction was observed. From the result basement of design and fabrication technology was obtained.

• 수산해양교육연구
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• 제9권1호
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• pp.83-97
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• 1997

Diesel engine is widely used for ship and industry source of power because of its high thermal efficiency and reliability and durability. However it lead to air pollution due to exhaust gas, and it is important to develop diesel engine of lower air-pollution to decrease the hazardous exhaust gas emissions. As one of the ways, the study for practically using the high pressure of fuel injection and variable injection timing system is being processing. The high pressure injection, which is said to be an effective means for reducing both NOx and particulate emissions, and great improvements in combustion characteristics have been reported by many researchers. In this study, electronic-hydraulic fuel injection system and hydraulic fuel injector system have been applied to the D.I. test engine for high pressure injection and variable injection timing. The injection pressure and injection rate depending upon accumulator pressure were measured with strain gage and Bosch injection rate measuring system before fitting the system into test engine, and analyzed the characteristics of the injection system. The combustion characteristics with this injection system has been analyzed with data concerning heat release rate, pressure rising rate, ignition point, ignition delay and maximum pressure value.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.119-120
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• 2014

In this study, we looked into the method to establish fire growth rate by buildings use for growing fire at the beginning of a fire considering the characteristics of the combustibles in a performance-based design. Actual conditions survey and literature review were carried out for the fire load and exposed surface area of combustibles to establish design fire by domestic building use. As a results, a simplified prediction equation of fire growth rate which depends on fire load and weight of combustibles could be derived by calculating the relation between the fire load and the fire growth rate of an initial fire through investigation of combustibles by domestic building use.Also, as a result of analyzing the placement of combustibles and location of the ignition source, it was found that the influence of the materials of the combustibles and the materials of the combustibles adjacent to the ignition source is big. Though 4 different experiments were carried out for the evaluation, the result of comparing the findings with those of FGR model showed that the fire growth rate was similarly derived.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.193-200
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• 1997

Flame spread and heat release properties and incident heat flux of interior materials subject to an igniter heat flux in a compartment are investigated and compared by using computer model. A comer fire ignition source is maintained for 10 minutes at 100 kw and subsequently increased to 300kw. In executing the model, base-line material properties are selected and one is changed for each run. Also 4 different igniter heat flux conditions and examined. Results are compared for the 12 different materials tested by the ISO Room Comer Test (9705). The time for total energy release rate to reach 1MW is examined. The parameters considered include flame heat flux and thermal inertia, lateral flame spread parameter, heat of combustion and effective heat of gasfication. The model can show the importance of each property in causing fire growth on interior Hnish materials in a compartment. The effect of ignitor heat flux and material property effects were demonstrated by using dimensionless parameters a, b and Tb. Results show that for b greater than about zero, flashover time in the ISO Room-Corner test is principally proportional to ignition time and nothing more.

• 방재기술
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• 통권14호
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• pp.13-17
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• 1993

We intended to apprehend the ignitability of the wood, using the ISO test for the ignitability accessment. So we first conducted the ISO test on eight kings of the wood as sample, which came from domestic for-est, and discovered the tendency of the ignitability for the wood in the condition of external factors(its density and the rate of water content, humidity). Finally it was found that the ignition time of the wood was effected by its density and, the rate of water content, the humidity in the atmosphere.

• International Journal of Automotive Technology
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• 제4권1호
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• pp.47-55
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• 2003

The Center for Transportation Research at the Argonne National Laboratory (ANL) supports the DOE by evaluating advanced automotive technologies in a systems context. ha has developed a unique set of compatible simulation tools and test equipment to perform an integrated systems analysis project from modeling through hardware testing and validation. This project utilized these capabilities to demonstrate the trade-off in fuel economy and Oxides of Nitrogen (NOx) emissions in a so-called ‘pre-transmission’ parallel hybrid powertrain. The powertrain configuration (in simulation and on the dynamometer) consists of a Compression Ignition Direct Ignition (CIDI) engine, a Continuously Variable Transmission (CVT) and an electric drive motor coupled to the CVT input shaft. The trade-off is studied in a simulated environment using PSAT with different controllers (fuzzy logic and rule based) and engine models (neural network and steady state models developed from ANL data).