초기 직경 변화가 Toluene 액적의 Soot 생성에 미치는 영향

임영찬 ( Young Chan Lim ),서현규 ( Hyun Kyu Suh ) 한국분무공학회 2015 한국액체미립화학회지 Vol.20 No.4

The main purpose of this study is to provide the information of soot generation of toluene fuel droplet. To achieve this, this paper provides the experimental results on the different initial diameter of toluene droplet combustion characteristics conducted under equivalent ambient pressure (Pamb) and oxygen concentration (O2) conditions. Visualization of single fuel droplet was performed with high resolution CCD camera and visualization system. At the same time, ambient pressure (Pamb) and oxygen concentration (O2) were maintained by ambient condition control system. Soot volume fraction ( fv) was analyzed and compared on the basis of intensity ratio (I/I0) of background image. The result of soot generation was almost the same regardless of initial droplet diameter since thermophoretic flux is not much changed under the same ambient conditions. Soot standoff ratio (SSR) of 2 mm diameter showed unstable variation characteristics due to the short available measuring time.

n-heptane 연료 혼합비에 따른 n-butanol 연료의 연소 성능에 관한 해석적 연구

임영찬(Young Chan Lim),서현규(Hyun Kyu Suh) 한국연소학회 2015 KOSCOSYMPOSIUM논문집 Vol.2015 No.5

나노유체 : 초기 직경 변화에 따른 Toluene 액적의 연소 특성

임영찬 ( Young Chan Lim ),서현규 ( Hyun Kyu Suh ) 한국액체미립화학회 2015 한국액체미립화학회 학술강연회 논문집 Vol.2015 No.-

The main purpose of this study is to provide the information of soot generation of toluene fuel droplet. To achieve this, this paper provides the experimental results on the different initial diameter of toluene droplet combustion characteristics conducted under equivalent ambient pressure(P(amb)) and oxygen concentration(O2) conditions. Visualization of single fuel droplet was performed with high resolution CCD camera and visualization system. At the same time, ambient pressure(P(amb)) and oxygen concentration(O2) was maintained by ambient condition control system. Soot volume fraction(f(v)) was analyzed and compared on the basis of intensity ratio(I/I0) of background image. The result of soot generation was almost the same regardless of initial droplet diameter since thermophoretic flux is not much changed under the same ambient conditions. Soot standoff ratio(SSR) of 2mm diameter showed unstable variation characteristics due to the short available measuring time.

알케인계 단일 연료 액적의 Soot 생성 특성에 관한 실험적 연구

임영찬 ( Young Chan Lim ),서현규 ( Hyun Kyu Suh ) 한국액체미립화학회 2017 한국액체미립화학회지 Vol.22 No.2

The soot formation characteristics of various alkane-based single fuel droplets were studied in this work. Also, This study was performed to provide the database of the soot behavior and formation of alkane-based single fuel droplet. The experi-mental conditions were set to 1.0 atm of ambient pressure (P_amb), 21% of oxygen concentration (O₂) and 79% of nitrogen concentration (N₂). Combustion and soot formation of single fuel droplet was visualized by visualization system with high speed camera. At the same time, ambient pressure, oxygen concentration and nitrogen concentration were maintained by ambient condition control system. Soot formation characteristics was analyzed and compared on the basis of intensity ratio (I/I₀) of background image. The results of toluene fuel droplet showed the largest soot generation. Soot volume fraction (f_v) was almost the same under the identical fuel types regardless of various initial droplet diameter (d₀) since thermophoretic flux was not much changed under the same ambient conditions.

분위기 조건이 Decane 액적의 Soot 생성에 미치는 영향

임영찬 ( Young Chan Lim ),서현규 ( Hyun Kyu Suh ) 한국분무공학회 2014 한국액체미립화학회지 Vol.19 No.4

The main purpose of this study is to provide basic information of droplet soot generation of decane fuel. To achieve this, this paper presents the experimental results on the decane droplet combustion conducted under various ambient pressure(Pamb), and oxygen concentration(O2) conditions. At the same time, the experimental study was conducted in terms of soot volume fraction(fv) and its maximum value. Also, visualization of single fuel droplet was conducted by high resolution CCD camera and ambient pressure(Pamb) and oxygen concentration(O2) was changed by control system. It was revealed that higher ambient pressure(Pamb), and oxygen concentration(O2) enhanced the soot generation and improved the maximum soot volume fraction(fv).

단파장 필터링을 통한 단일 액적 화염 내 CH₂O, CH, C₂ 화학종 분석 및 액적 연소 특성

임영찬(Young Chan Lim),서현규(Hyun Kyu Suh) 한국연소학회 2021 한국연소학회지 Vol.26 No.3

This paper was performed to observe the flame behavior of the biodiesel, diesel, and n-heptane single fuel droplets and analyze the CH₂O, CH, and C₂ species in a single droplet flame included combustion characteristics experimentally. In order to visualize the combustion process of test fuel droplets, droplet combustion visualization and analysis were conducted using a high-speed camera and a CCD camera coupled with a short wavelength filter. A single fuel droplet was formed on the stainless wire using a syringe and ignited by a heat source provided from the power supply equipment. It was shown that the ignition delay of an n-heptane fuel droplet was shorter than those of biodiesel and diesel fuel droplets due to a higher evaporation rate in the liquid phase. A longer flame extinction and the flame life-time were also observed in the biodiesel and diesel fuel droplets than most n-heptane fuel droplets. In the case of the diesel fuel droplet, it was found that the flame life-time was slightly increased than the biodiesel fuel droplet. The C₂ species produced in the flame during combustion of all fuel droplets were distributed throughout the flame, while the CH and CH₂O chemical species tended to be located in the flame front and center area. As a result of combustion analysis, the biodiesel, diesel, and n-heptane fuels were shown the changes of the CH₂O mole fraction according to the two-stage combustion characteristics, and the mole fraction of CH species was decreased by CH + O₂ and CH + H₂O chemical reactions.

당량비 변화에 따른 바이오디젤 연소 및 CO, NO<SUB>X</SUB> 생성 특성 예측

임영찬(Young Chan Lim),서현규(Hyun Kyu Suh) 한국연소학회 2016 한국연소학회지 Vol.21 No.1

This study was performed to provide the basic information of the combustion, CO and NOX characteristics of biodiesel in accordance with equivalence ratio. The closed homogeneous reactor model used for the analysis. The analysis conditions were set to 900 K of the initial temperature, 20 atm of initial pressure and equivalence ratio was changes from 0.6 to 1.4. The results of analysis were predicted and compared in terms of combustion temperature, combustion pressure, CO and NOX emissions. The results of combustion characteristics showed that ignition delay was decreased and the combustion temperature and combustion pressure was increased in accordance with equivalence ratio. CO emission was decreased in lean condition(Φ< 1.0), however, CO emission was increased in rich condition(Φ> 1.0) because oxygen supply insufficient. NOX emission showed the largest amount in condition 0.8 of equivalence ratio because the oxygen concentration was sufficient.

단파장 필터링을 통한 연료 액적의 화염 거동 특성 분석

임영찬 ( Young Chan Lim ),정준우 ( Jun Woo Jung ),서현규 ( Hyun Kyu Suh ) 한국액체미립화학회 2018 한국액체미립화학회 학술강연회 논문집 Vol.2018 No.-

This experimental study was investigated to observe the flame behavior of biodiesel, diesel, and n-heptane fuel droplets in normal gravity condition. It will expect to provide basic information on the ignition delay, and flame propagation speed of these fuel droplets. In order to visualize the combustion process of test fuels, droplet combustion visualization and analysis were conducted using a high speed camera and the CCD camera. Single fuel droplet was formed on stainless wire using a syringe pump and was combusted using the power supply equipment. The ignition delay of n-heptane fuel droplet became shorter than those of biodiesel and diesel fuel droplets due to the lowest boiling point and volatility characteristics. In addition, the flame propagation speed was similar regardless of the initial droplet diameter(d0). However, the flame propagation speed of biodiesel droplet increased in the range from 1.428 mm to 1.542 mm of initial droplet diameter.

고온, 고압의 분위기 변화가 n-butanol 및 n-heptane 연료의 연소 특성에 미치는 영향

임영찬 ( Young Chan Lim ),서현규 ( Hyun Kyu Suh ) 한국분무공학회 2016 한국액체미립화학회지 Vol.21 No.1

The effect of high ambient temperature and pressure conditions on the combustion performance of n-butanol, n-heptane and its mixing fuel (BH 20) were studied in this work. To reveal this, the closed homogeneous reactor model applied and 1000-1200 K of the initial temperature, 20-30 atm of initial pressure and 1.0 of equivalence ratio were set to numerical analysis. It was found that the results of combustion temperature was increased and the ignition delay was decreased when the ambient conditions were elevated since the combustion reactivity increased at the high ambient conditions. On the contrary, under the low combustion temperature condition, the combustion pressure was more influenced by the ambient temperature in the same ambient conditions. In addition, the total mass and the mass density of tested fuels were influenced by the ambient pressure and temperature. Also, soot generation of mixing fuel was decreased than n-heptane fuel due to the oxygen content of n-butanol fuel.

정적 연소 조건에서 Octane 단일 연료 액적의 매연 생성 거동에 관한 연구

임영찬(Young Chan Lim),서현규(Hyun Kyu Suh) 대한기계학회 2017 大韓機械學會論文集B Vol.41 No.6

본 연구는 정적 연소 조건에서 Octane 단일 연료 액적의 매연 생성 거동에 관한 정보를 제공하기 위해 수행하였다. 이를 위해 동일한 분위기 압력(Pamb) 1.0 atm과 산소 농도(O2) 21%, 질소 농도(N2) 79% 조건에서 초기 액적 직경(d0) 변화에 따른 Octane 액적의 매연 생성 특성 실험 결과를 제시하였다. Octane 액적 연소 가시화는 초고속 카메라를 사용하여 촬영하였고, 분위기 조건은 제어 시스템에 의해 동일한 조건을 유지하였다. Octane 액적 연소 결과, 매연 생성량은 동일한 분위기 조건에서 초기 액적 직경 변화의 영향이 크게 나타나지 않았다. 또한, 매연 체적 분율 최댓값(fvmax)은 135°~315° 측정 방향에서 높은 결과를 보였다. 이는 액적 점화 이후 Igniter의 이동 과정에서 생성된 Soot-tail로 인해 매연 체적분율 결과가 증가된 것으로 나타났다. This study was performed to provide the information of the soot formation behavior of octane single fuel droplet under the identical combustion conditions. To achieve this, this experimental study provide the results of the soot formation characteristics of octane droplet in accordance with different initial droplet diameter(d0), at the same time, experiment was conducted under the same combustion conditions which are 1.0atm of ambient pressure(Pamb), 21% of oxygen concentration(O2) and 79% of nitrogen concentration(N2). Visualization of octane droplet combustion was performed by visualization system with high speed camera. The results of maximum soot volume fraction(fvmax) was almost the same under the equivalent ambient conditions regardless of initial droplet diameter. Furthermore, maximum soot volume fraction was showed the higher value in the measuring direction between 135° and 315° since the soot-tail is generated during two opposing igniters movement process.