http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
정적 연소기 내 LNG-Diesel 혼소 특성에 관한 수치해석적 연구
서현욱(Hyunuk Suh),배재옥(Jaeok Bae),최민수(Minsu Choi),전충환(Chunghwan Jeon) 한국자동차공학회 2013 한국자동차공학회 부문종합 학술대회 Vol.2013 No.5
The objective of this numerical study is to investigate the dual-fuel combustion characteristics and emissions including NO, Soot in Diesel with LNG. Simulations are performed in CVCC mesh structure of which initial conditions are including LNG mass fraction. As a result of LNG addition, pressure rises rapidly because of premixed gas combustion of LNG and NO emission production becomes lower due to fast combustion. Soot emission becomes lower until α=0.45, but higher to 170% comparison with diesel combustion over that fraction. CO emission looks likely to follow the soot emission tendency. This may mean that incomplete combustion caused by high LNG fraction accelerates the soot production. COx emission including CO and CO2 gets lower by reason of lower carbon content of LNG as compared that of diesel.
점화 모델에 따른 발전용 디젤 엔진의 연소 특성에 관한 수치적 연구
서현욱(Hyunuk Suh),배재옥(Jaeok Bae),이병화(Byeonghwa Lee),한동식(Dongsik Han),전충환(Chunghwan Jeon) 한국자동차공학회 2013 한국자동차공학회 지부 학술대회 논문집 Vol.2013 No.4
The objective of this numerical study is to evaluate the results of the simulation of which ignition models are diesel and shell. Power generation diesel engine used for this study has bore of 160mm, stroke of 240mm and compression ratio of 15.2. This study contains experimental result and numerical result calculated by STAR-CD and AVL-Fire. Pressure data of AVL-Fire has a 15~20bar maximum error compared with experimental pressure data in peak pressure range. Especially, Shell ignition model has a different shape of pressure and heat release rate curve increased and decreased rapidly. NO and Soot emissions in diesel ignition model are lower than those in shell ignition model which may be due to fast combustion. Finally, replacement of ignition model causes quite different numerical results and diesel ignition model may be appropriate for diesel combustion in AVL-Fire.
서현욱(Hyunuk Suh),배재옥(Jaeok Bae),최민수(Minsu Choi),전충환(Chunghwan Jeon) 한국자동차공학회 2013 한국자동차공학회 지부 학술대회 논문집 Vol.2013 No.11
Diesel engine has a advantage to obtain a high thermal efficiency and high power output, but emissions such as PM has become a problem caused by diffusion flame. In order to solve this problem, dual fuel engine using diesel fuel and gas has been developed, for which research is not enough. Therefore, the objective of this study is to investigate the characteristics of the diesel spray by injecting diesel into the Constant Volume Combustion Chamber of which ambient condition is premixed with methane gas 5%, 10%. As a result, spray tip penetration increase and spray cone angle decrease due to decline of internal gas density according to growth of methane gas fraction.
LNG를 첨가한 대형디젤엔진의 연소 및 배기 특성에 관한 수치해석적 연구
최민수(Minsu Choi),배재옥(Jaeok Bae),서현욱(Hyunuk Suh),한동식(Dongsik Han),전충환(Chunghwan Jeon) 한국자동차공학회 2013 한국자동차공학회 부문종합 학술대회 Vol.2013 No.5
The objective of this numerical investigation is to analyze characteristics of combustion and emission on various LNG percent in LNG-Diesel dual fuel engine by using AVL-FIRE. The diesel engine makes soot but it is available to reduce soot by addition to LNG. This numerical study was implemented under conditions with LNG percents 0%, 15%, 30%, 45%, 60%, 75%. As a result, the higher LNG percent is, the higher peak pressure and temperature is. But ignition delay and combustion duration tend to decrease compared to that of diesel combustion. In emissions, NO, CO are increased and Soot(except for LNG 75%), CO₂ are decreased in the case of high LNG percent. Thus, it is necessary to find proper LNG percent.
후분사를 적용한 대형디젤엔진의 연소 및 배기 특성에 관한 수치해석적 연구
최민수(Minsu Choi),배재옥(Jaeok Bae),서현욱(Hyunuk Suh),이병화(Byunghwa Lee),전충환(Chunghwan Jeon) 한국자동차공학회 2014 한국 자동차공학회논문집 Vol.22 No.1
A numerical study has been carried out to analyze the combustion characteristics in heavy duty diesel engine with post injection for reducing NO emission. For verification of numerical study results, calculated cylinder pressure was matched to experimental data. In this study, post injection timing and amount of post injection were modified as parameters, but the total amount of injection fuel was maintained. As the results, maximum cylinder pressure increases above minimum 2% by post injection and end of pressure curve is decreased rapidly. The more dwell time and amount of post injection fuel are, the more pressure drop occurs. And trade-off relation of NO and soot are appeared. In the results, NO was reduced without deterioration of cylinder pressure under condition of 10° CA dwell time and main 60%, post 40% fuel portion.
후분사시기가 대형디젤엔진의 연소 및 배기에 미치는 영향에 관한 수치해석적 연구
최민수(Minsu Choi),배재옥(Jaeok Bae),서현욱(Hyunuk Suh),이병화(Byunghwa Lee),전충환(Chunghwan Jeon) 한국자동차공학회 2013 한국자동차공학회 지부 학술대회 논문집 Vol.2013 No.11
The objective of this numerical investigation is to analyze characteristics of combustion and emission on various post injection timing in heavy duty diesel engine by using AVL-FIRE. The diesel engine makes NO but it is available to reduce NO by addition to post injection. This numerical study was implemented under conditions with post injection timing 10CA, 20CA. As a result, the longer dwell time is, the higher peak pressure. But end of pressure curve tended to decrease compared to single injection. In emissions, NO was decreased and soot was increased in the case of longer dwell time. Thus, it is available to decrease NO formation.