• 한국안전학회지
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• 제28권2호
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• pp.49-54
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• 2013

The autoignition temperature(AIT) is important index for the safe handling of flammable liquids which constitute the solvent mixtures. This study measured the AITs and ignition delay time for n-Decane and Acetic acid system by using ASTM E659 apparatus. The AITs of n-Decane and Acetic acid which constituted binary system were $212^{\circ}C$ and $512^{\circ}C$, respectively. The experimental AITs of n-Decane and Acetic acid system were a good agreement with the calculated AITs by the proposed equations with a few A.A.D.(average absolute deviation). And n-Decane and Acetic acid system was shown the minimum autoignition temperature behavior(MAITB).

• 한국분무공학회지
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• 제26권3호
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• pp.142-148
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• 2021

The objective of this study is to analyze the basic flame behavior characteristics using the single fuel droplet combustion of diesel, palm-based biodiesel, and canola-based biodiesel. The results were compared and analyzed through the post processed image, which was applied the threshold level for removing noise in the raw image. The raw image was taken by a high-speed camera during the entire combustion process. At the same time, the maximum flame length, which was measured by the application code of the MATLAB program, the ignition delay, and the combustion period were compared and analyzed.

• 한국연소학회지
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• 제4권1호
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• pp.17-26
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• 1999

Vaporization, ignition and combustion of fuel droplets in tandem array are theoretically investigated to understand the droplet interactions in combustors. Including the effects of density variation in gas-phase, internal circulation and transient liquid heating, a numerical studies are performed by changing parameters such as initial droplet temperatures, initial droplet spacings, initial Reynolds numbers, surrounding gas temperatures, and activation energies of fuel vapors. Combustion regime maps classify the droplet combustion phenomena according to the configuration and location of the flame with respect to injection Reynolds numbers and surrounding gas temperatures. In addition, it is shown that the dynamic histories of droplets and ignition delay times are dependent on droplet size ratios and initial spacings of tandem droplets.

• 한국안전학회지
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• 제30권2호
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• pp.21-26
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• 2015

For the safe handling of o-cresol, this study was investigated the explosion limits of o-cresol in the reference data. The flash points and AITs(auto-ignition temperatures) by ignition delay time were experimented. The lower flash points of o-cresol by using closed-cup tester were experimented in $77^{\circ}C$ and $80^{\circ}C$. The lower flash points of o-cresol by using open cup tester were experimented in $86^{\circ}C$ and $87^{\circ}C$. This study measured relationship between the AITs and the ignition delay times by using ASTM E659 tester for o-cresol. The AIT of o-cresol was experimented as $495^{\circ}C$. The lower explosion limit(LEL) by the measured the lower flash point for o-cresol was calculated as 1.27 Vol%.

• 한국자동차공학회논문집
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• 제6권1호
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• pp.205-212
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• 1998

In this study, the effects of water vapor in inlet air on combustion efficiency, general performance, knock characteristics and emission gas concentration were investig- ated through the experiments of combustion and vibration analyses, emission gas analysis by changing water vapor quantity in inlet air with temperature and humidity auto control unit. With partial vapor pressure increase, the brake torque at wide open throttle status decreased and the average ignition delay angle increased, IMEP (indicated mean effective pressured using the integral and 3rd derivatives of filtered cylinder pressure as knock intensity, which matched well with the method of frequency power spectrum of block vibration signal. Water vapor in intake air had influence on the spark knock sensitivity. With the increase of water vapor content in intake air NOx emission was decreased and HC emission was increased.

• 한국안전학회지
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• 제26권2호
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• pp.36-41
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• 2011

For the safe handling of n-hexane, the explosion limit at $25^{\circ}C$, the temperature dependence of the explosion limits and the lower flash point were investigated. And AITs(auto-ignition temperatures) by ignition delay time for n-hexane were experimented. By using the literatures data, the lower and upper explosion limits of n-hexane recommended 1.0 Vol% and 8.0 Vol%, respectively. In this study, the lower flash points of n-hexane recommended $-23^{\circ}C$. This study measured relationship between the AITs and the ignition delay times by using ASTM E659-78 apparatus for n-hexane, and the experimental AIT of n-hexane was $240^{\circ}C$. The new equations for predicting the temperature dependence of the explosion limits of n-hexane is proposed. The values calculated by the proposed equations were a good agreement with the literature data.

• 한국안전학회지
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• 제27권3호
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• pp.83-88
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• 2012

For the safe handling of n-tridecane, the lower flash points and AITs(auto-ignition temperatures) by ignition delay time were experimented. Also lower explosion limits by the lower flash points were calculated. The lower flash points of n-tridecane by using closed-cup tester were experimented $92^{\circ}C$ and $96^{\circ}C$. The lower flash points and fire point of n-tridecane by using open cup tester were experimented 100 oC and 103 oC, respectively. This study measured relationship between the AITs and the ignition delay times by using ASTM E659 apparatus for n-tridecane. The experimental AIT of n-tridecane was 223 oC. The calculated lower explosion limit by using measured lower flash point 92 oC for n-tridecane was 0.6 Vol.%.

• 한국안전학회지
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• 제29권4호
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• pp.85-90
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• 2014

For the safe handling of acetic anhydride, this study was investigated the explosion limits of acetic anhydride in the reference data. And the lower flash points, upper flash points, and AITs(auto-ignition temperatures) by ignition delay time were experimented. The lower and upper explosion limits of acetic anhydride by the investigation of the literatures recommended 2.9 Vol% and 10.3 Vol.%, respectively. The lower flash point of acetic anhydride by using Setaflash closed-cup tester was experimented $49^{\circ}C$. The lower flash point acetic anhydride by using Tag and Cleveland open cup tester were experimented $55^{\circ}C$and $62^{\circ}C$, respectively. Also, this study measured relationship between the AITs and the ignition delay times by using ASTM E659 tester for acetic anhydride. The experimental AIT of acetic anhydride was $350^{\circ}C$.

• 대한기계학회논문집B
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• 제41권11호
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• pp.749-757
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• 2017

본 연구는 대체연료 개발 및 국제환경규제에 대응하기 위하여, 노말데케인과 에탄올 혼합연료의 조성 및 온도 변화가 자착화 특성에 미치는 영향을 수치적으로 해석하였다. 해석용 프로그램으로는 CHEMKIN-PRO를 사용하였고, 반응모델은 LLNL모델을 이용하였다. 수치해석 결과를 통해 저온 연소 반응이 일어나는 1000K 이하에서는 에탄올의 몰 비율이 증가함에 따라 점화지연 시간이 증가하는 현상을 확인하였다. 에탄올의 높은 옥탄가로 인해 에탄올의 높은 비율은 점화를 일으키는 OH라디칼의 농도 증가를 지연시키기 때문이다. 배기가스 재순환을 적용하기 위해 혼합연료에 산소농도를 변화하여 수치해석을 하였다. 산소농도가 감소함에 따라 전체 점화지연시간은 증가하게 되고, 이는 질소가스가 연소실 내에 열부하로 작용하기 때문이다.

• 대한기계학회논문집
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• 제17권7호
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• pp.1823-1832
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• 1993

CWS(coal-water slurry) is used for application in power plants, boilers, industrial furnaces. A single coal-water slurry droplet ignition has been examined to reveal the basic nature of their evaporation, volatilization and heating processes. The interior droplet temperature distribution has been considered. The effect of coal thermal conductivity, droplet size, water fraction in the slurry, gas temperature and velocity and radiation on the ignition phenomena were also studied. Either increasing the velocity and gas temperature or decreasing the droplet size and water fraction in the slurry may reduce the time for evaporation and ignition delay time.