• Journal of Advanced Marine Engineering and Technology
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• 제26권1호
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• pp.132-137
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• 2002

Recently, impinging spray is used for atomization of diesel engine, but it bring on adhesion of fuel. Therefore, we studied about droplet behavior on high temperature plate changing the size of droplet, surface temperatures, and surface roughness of plate. In this study, We studied to confirm experimentally about mechanism of evaporation and ignition process of single fuel droplet. We observed evaporation time, evaporation appearance and ignition delay time by the photopraphs of 8mm video camera. Experimental results are summarized as follows: 1. The boiling point of fuel affect a evaporation and ignition process. 2. The surface roughness affect a evaporation time. 3. The ignition delay time relate to evaporation characteristic.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제25회 KOSCI SYMPOSIUM 논문집
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• pp.25-31
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• 2002

For the better understanding of the stability of turbulent combustion, more researches on extinction and re-ignition are needed. Flame interactions in non-premixed flame have also not been greatly researched. We made a hybrid twin jet flame, the combinations of diffusion flame and partially-premixed diffusion flame, in a twin jet counterflow configuration. The extinction limits of a crossed twin jet counterflow have been extended in comparison with those of a one-dimensional counterflow because of flame interactions through heat transfer and joint ownership of various radicals. Besides, we have obtain ignition $Damk\"{o}hler$ number by experimental method without external ignition source using the extinction characteristic in a crossed twin jet counterflow flame. From results, we can identify the hysteresis between extinction and ignition $Damk\"{o}hler$ number in S-curve.

• 한국자동차공학회논문집
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• 제12권3호
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• pp.75-82
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• 2004

The allowable exhaust standard has been intensified as a part of the countermeasure to decrease air pollution in the world. As the cars with an alternative fuel starts to get into the spotlight, the cars with low emission has been introduced and exhaust gas regulation forced in this country. These days, LPG vehicles, which infrastructure of fuel was already built up, and CNG vehicles are recognized for alternative fuel cars in this country. In this study, the constant volume combustion chamber was manufactured and used for experiments to obtain the ignition characteristics of LPG fuel and the optimal ignition energy. The experiment measured the combustion characteristics, in regard to the change of combustion variable, and the change of ignition energy. During the combustion of fuel, the maximum temperature inside the combustion chamber is higher when the initial pressure is higher. The burning velocity also seems to have the same characteristic as the temperature. However, the heat flux did not change much with the theoretical correct mixture but the various initial temperature of the combustion chamber. The heat flux got faster and ignition energy bigger as the dwell time of the ignition system expanded. When the dwell time get longer, the ignition energy also increased then fixed. The ignition energy increased as the initial pressure inside the combustion chamber higher. The heat flux got faster as the dwell time expanded.

• 오토저널
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• 제10권3호
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• pp.60-65
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• 1988

The ignition characteristics of repetitive electric sparks into a quiescent acetylene-air premixture and LPG-argon-air premixture was investigated by using a home-made Repetitive-Spark-Generator(RSG) to elucidate the effect of fuel burning velocity to ignition ability of RSG. Results show that the optimum spark delay time interval is strongly related with fuel burning velocity, or implicitly with characteristic reaction time scale of each fuel.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 제33회 추계학술대회논문집
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• pp.130-133
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• 2009

액체 로켓 엔진의 경우 작동초기인 점화와 마지막의 소염시의 추진제 공급 순서는 안정적으로 시스템을 운영하는데 많은 영향을 끼친다. 안정적인 엔진의 작동확인을 위해 점화할 때 공급순서와 소염할 때 추진제의 공급 순서를 바꾸어 가면서 연소 실험을 수행 하였다. 본 연구에 사용된 분사기는 과산화수소와 케로신을 추진제로 사용하는 동축 스월형이며, 점화 방식은 촉매 점화를 방식을 사용하였다. 본 실험을 통해서 액체로켓엔진의 연소 시험을 안정적으로 수행하기 위해 점화와 소염할 때의 최적의 시퀀스를 찾아내었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 제33회 추계학술대회논문집
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• pp.74-77
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• 2009

본 연구에서는 과산화수소/케로신 촉매 점화기의 최적 설계를 위하여 점화기 설계와 운용 조건에 따른 점화 특성을 확인하였다. 그 결과 촉매대의 출구 면적은 분해된 가스가 쵸킹이 발생하지 않도록 충분하여야 하며, 케로신은 촉매대 중앙에서 미립화가 잘되도록 분무하여야 함을 확인하였다. 또한 점화기를 운용하는데 있어 예열이 없을 경우 과산화수소를 약 3초 정도 리드해야 하며, 퍼지는 케로신 공급과 같거나 늦게 공급하는 것이 바람직함을 확인하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.2088-2093
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• 2004

Harmful elements from the exhaust gases are caused by incomplete combustion of mixture inside the engine cylinder and this abnormal combustion like misfire or partial burning is the direct cause of the air pollution and engine performance degradation. In this study, I obtain the shapes of spark, voltage and current generated when changing the experimental parameters such as grounded electrode shapes, electrode gap and the material of center electrodes. After that, I produce ignition energy by using the voltage and current and classify ignition energy into capacitive discharge energy and inductive discharge energy.

• 대한기계학회논문집
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• 제13권4호
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• pp.703-707
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• 1989

본 연구에서는 반무한체에 대하여 활성화 에너지가 매우 큰 경우의 점근법을 적용하여 이 두 변수의 시간에 따른 변화가 점화지연시간에 미치는 영향을 해석적으로 알아보고 참고문헌(1)의 실험치와 비교하고자 한다.

• 한국군사과학기술학회지
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• 제14권1호
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• pp.22-29
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• 2011

Using the numerical code for the interior ballistics, the performance of the interior ballistics with the characteristic of the ignition-gas injections has been investigated. The ignition gas has been assumed to be injected into the chamber with 3 cases. As the results of analysis, when the ignition-gas has been injected into all chamber area, the pressure distributions of the chamber of the interior ballistics have been uniform and the differential pressure has been stable. The ignition-gas has been injected into the partial area of the chamber, however, the pressure distributions and the differential pressure have been unstable. The case using the longer ignition injector, therefore, seems to be more suitable to improve the stability of the interior ballistics.

• 한국추진공학회지
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• 제23권2호
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• pp.13-20
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• 2019

본 연구에서는 석유계항공유와 혼합하여 사용이 가능한 바이오항공유의 혼합 비율에 따른 점화지연 특성의 변화를 확인하기 위하여, 두 항공유를 일정한 비율로 혼합한 시료의 점화지연시간을 측정하여 분석하였다. 측정한 모든 온도 조건에서 Bio-6308의 점화지연시간이 Jet A-1의 점화지연시간보다 짧게 나타났으며, 두 항공유를 일정한 비율로 혼합한 경우에도 Bio-6308의 함량이 증가할수록 점화지연시간은 짧아지는 경향을 보였는데, 이는 Jet A-1을 구성하는 방향족 화합물의 영향 때문임을 n-heptane/Toluene의 점화지연시간 측정을 통해 확인하였다.