• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 B
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• pp.706-708
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• 1998

Recently, it was very difficult for hydraulic governor to regulate the speed of high power engine with long stroke at low speed and low load, because of the jiggling phenomena by rough fluctuation of rotating torque and the hunting phenomena by long dead time occurred in fuel combustion process in the engine cylinder. In this paper, the influence of engine dead time is investigated by Nickels chart, and hybrid controller selected advantages of PID and fuzzy logic controller is provided to improve the performance of speed control of a low speed and long stroke diesel engine.

• 한국분무공학회지
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• 제3권1호
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• pp.10-18
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• 1998

To investigate the in-cylinder phenomena in a SI engine with 3 valves and pent-roof type combustion chamber, flow fields, fuel distributions, and flame propagations were measured in a single c!'tinder visualized engine. Flow fields were visualized by PTV system during the intake and compression process. Fuel distributions were measured by PLIF at the various engine conditions including the cold and hot engine conditions and the effect of air-shrouded injector on the fuel distribution was investigated also. In addition, flame propagation patterns were characterized.

• 한국분무공학회지
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• 제23권2호
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• pp.90-95
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• 2018

The goal of this study is to experimentally observe the autoignition phenomena of a diesel/1-butanol mixture droplet in ambient pressure and $700^{\circ}C$ condition. A volume ratio of 1-butanol in the fuel was set to 25, 50 and 75%. A single droplet was installed at the tip of fine thermocouple, and the electric furnace dropped down to make elevated temperature condition. Droplet behavior during the experiment could be divided into 3 stages including droplet heating, puffing and autoignition/combustion. Puffing process intensively observed for the case of 1-butanol volume ratio of 25 and 50%, but did not occur at 75%. Increase of 1-butanol volume ratio hindered rise of the droplet temperature and delayed ignition. In addition, puffing process also affected on autoignition, so the ignition delay of 1-butanol volume ratio of 50% was became longer than that of 75% case.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.247-248
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• 2015

Korea rapidly arranged urbanization and overpopulation with high growth of economy and all kinds of decrepit facilities are scattered all over the downtown. If there is a strong wind in fire, fire is rapidly increased by various fire spread factors. And Korea cannot build prediction model of urban fire combustion phenomena because there is no studies that physically explains the suitable flame phenomena for its real state. In this study, for development of Korean Urban fire Simulation on Attenuation of Radiant Heat Flux from Water Screen.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2001년도 춘계학술대회 논문집
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• pp.75-90
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• 2001

For the purpose of helping development of a GDI(Gasoline Direct Injection) engine, the in-cylinder phenomena, such as the spray behaviors and fuel distributions, unburned fuel, and flame characteristics were investigated in a single cylinder GDI engine. The GDI engine was equipped with a swirl type electronic injector and SCV(Swirl Control Valve). PLIF(Planar Laser Induced Fluorescence) system with KrF Excimer laser was used for the measurements of the fuel distributions. The effects of the injector specifications, such as the spray cone angle and the offset angle on the fuel distributions and combustion characteristics were investigated. As a result, it was found that the injected fuel spray collided with the bottom of the bowl and moved upward along the exhaust side wall of the piston bowl. This fuel vapor played a important role in the instance of spark ignition. The injector specifications has a great influence on the flame characteristics.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.226-227
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• 2013

Korea rapidly arranged urbanization and overpopulation with high growth of economy and all kinds of decrepit facilities are scattered all over the downtown. If there is a strong wind in fire, fire is rapidly increased by various fire spread factors. And Korea cannot build prediction model of urban fire combustion phenomena because there is no studies that physically explains the suitable flame phenomena for its real state. In this study, based on the Japanese Urban fire simulation to target the building congested Area and suitability of fire risk assessment were reviewed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.87-88
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• 2013

Korea rapidly arranged urbanization and overpopulation with high growth of economy and all kinds of decrepit facilities are scattered all over the downtown. If there is a strong wind in fire, fire is rapidly increased by various fire spread factors. And Korea cannot build prediction model of urban fire combustion phenomena because there is no studies that physically explains the suitable flame phenomena for its real state. In this study, based on the Japanese Urban fire simulation to target the wooden building congested Area and suitability of fire risk assessment were reviewed.

• 한국자동차공학회논문집
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• 제20권3호
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• pp.106-112
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• 2012

Since air pollution problem by emissions from automotive vehicles has become social issues, lean-burn gasoline direct injection (GDI) engine is focused as an alternative to meet the requirement of reinforced emission regulation and improved fuel consumption. Spray-guided type DI combustion is promising technology, which characterized by the centrally mounted injector and closely positioned spark plug, since stable lean combustion can be realized even at ultra-lean mixture condition. In the present study, the effect of multi-ignition with developed charge coil on combustion and emission characteristics was investigated in optical accessible single cylinder engine. In order to fully understand the in-cylinder phenomena and the mechanisms of emission production, optical diagnostics, such as flame visualization was also carried out at frequently using operating condition. Multi-ignition is effective to improve fuel economy but increase NOx emission at flammability limit.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.595-598
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• 2011

이중 연소 램제트(DCR) 엔진의 주 연소기에서 초음속 연소 현상을 수치해석을 동하여 연구하였다. 초음속 연소 유동은 유동의 압축성 효과에 연소 안정성이 크게 영향 받으므로, 일정 단면적 부분의 길이 및 확산 각에 대한 영향을 살펴보았다. 동일한 입구 조건에서의 해석의 결과 이중 연소 램제트 엔진 연소기의 연소 유동은 기본적으로 난류 부상 화염의 특징을 가짐을 알 수 있었으며, 부상 화염의 높이는 초음속 확산각이 작고 일정 단면적 부분이 긴 경우, 분사기 가까이 유지되만, 확산각의 변화에 심하게 영향 받아 작은 변화에도 부상화염의 높이가 크게 증가하거나 연소기 밖으로 blow-out 되므로, DCR 연소기의 설계에는 화염의 안정성이 충분히 고려되어야 함을 알 수 있었다.

• 한국화재소방학회논문지
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• 제24권6호
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• pp.145-152
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• 2010

실규모 ISO 9705 표준 화재실에서 환기부족 화재를 대상으로 연소효율 개념에 대한 검토가 수행되었다. 특히 구획 외부에서 측정되는 총괄연소효율과 구획 내부의 고온 상층부에서 측정된 국부연소효율의 개념을 비교.검토하였다. 연료로는 다양한 범위의 연소열과 그을음 생성량을 갖도록 헵탄, 톨루엔 및 이소프로판올이 사용되었다. 주요 결과로서, 총괄연소효율은 총괄당량비 증가에 따라 비교적 선형적으로 감소한다. 반면에 국부연소효율은 총괄당량비 증가에 따라 2차 곡선의 형태로 크게 감소됨을 확인하였다. 위 결과를 통해 국부연소효율에 대한 정보는 구획 내부의 화재현상을 이해하는데 매우 유용한 변수임을 알 수 있었다. 또한 국부연소효율은 구획화재에 대한 상사과정에서 중요한 변수로 사용될 수 있음을 논의하였다.