바이오디젤-가솔린-에탄올 저탄소 혼합연료가 탄소배출 저감에 미치는 영향 = Effects of biodiesel-gasoline-ethanol Low Carbon Blended Fuels on Carbon Emission Reduction

다국어 초록 (Multilingual Abstract)

The increasing urgency of global climate change and the tightening of emission regulations have accelerated the search for alternative fuels capable of reducing dependence on fossil diesel while achieving significant reductions in carbon emissions and pollutant formation. Biodiesel has emerged as one of the most promising renewable fuels due to its oxygenated molecular structure, low sulfur content, and biodegradability. However, its relatively high viscosity, lower volatility, and reduced heating value can hinder atomization and combustion efficiency, especially at low engine loads. To overcome these limitations, recent research has explored multi-component fuel blending strategies incorporating gasoline and ethanol, which offer high volatility and additional oxygen content that may enhance mixture formation, promote cleaner combustion, and contribute to carbon reduction. In this context, biodiesel–gasoline–ethanol blends represent a new class of low-carbon, high-oxygen multi-component fuels with the potential to improve combustion quality and simultaneously reduce CO2 and particulate emissions. However, the combined effects of these fuels on diesel engine combustion, energy efficiency, and regulated emissions, especially under varying engine loads, are not yet fully understood. Furthermore, exhaust gas recirculation (EGR), a widely applied NOx reduction technology, interacts strongly with fuel
oxygen content and ignition characteristics, and its effectiveness within these blended fuel systems requires detailed investigation.

The present study investigates the combustion characteristics and carbon emission reduction potential of biodiesel–gasoline–ethanol blends (B90G5E5,
B80G10E10, B70G15E15) in comparison with baseline diesel (B0) and pure biodiesel (B100). Experiments were conducted using a four-cylinder diesel engine at three load conditions (30, 60, 90 Nm) to evaluate in-cylinder pressure, heat release rate, brake specific fuel consumption (BSFC), and brake thermal efficiency (BTE). Regulated emissions including CO, CO2, HC, NOx, and PM were analyzed comprehensively. In addition, the influence of 10% EGR on combustion performance and emission behavior was examined for both B100 and high-ethanol blend B70G15E15 to elucidate the interaction between EGR dilution effects and oxygenated fuel characteristics. Through an integrated evaluation of combustion stability, engine performance, and emission outcomes, this study aims to identify the optimal blending strategy for achieving high efficiency and low carbon emissions in diesel engines. The findings provide important insights into the applicability of multi-component fuel blends as next-generation low-carbon fuels and the role of EGR in enhancing their environmental and combustion performance

목차 (Table of Contents)

• 제 1 장 서 론 1
• 1.1 연구배경 1
• 1.1.1 탄소중립의 개볌 및 필요성 1
• 1.1.2 저탄소 연료 개발의 필요성 3
• 1.2 주요 저탄소 연료의 비교 4
• 1.2.1 바이오디젤(Biodiesel) 4
• 1.2.2 메탄올(Methane) 6
• 1.2.3 에탄올(Ethanol) 8
• 1.3 연구목적 및 연구내용 10
• 1.3.1 연구목적 10
• 1.3.2 연구내용 11
• 제 2 장 이론적 배경 13
• 2.1 연소특성의 기초 이론 13
• 2.1.1 실린더 내 연소압력 (In-cylinder Combustion Pressure) 13
• 2.1.2 열발생율(Heat Release Rate) 14
• 2.2 기관성능의 기초 이론 17
• 2.2.1 제동연료소비율(Brake Specific Fuel Consumption, BSFC) 17
• 2.2.2 제동열효율(Brake Thermal Efficiency, BTE) 18
• 2.3 배기특성의 기초 이론 19
• 2.3.1 일산화탄소(Carbon Monoxide, CO) 19
• 2.3.2 이산화탄소(Carbon Dioxide, CO2) 20
• 2.3.3 탄화수소(hydrocarbons, HC) 21
• 2.3.4 질소산화물(Nitrogen Oxides, NOx) 22
• 2.3.5 입자상물질(Particulate Matter, PM) 24
• 제 3 장 실험장치 및 방법 25
• 3.1 실험장치 25
• 3.1.1 시험 엔진 구성 27
• 3.1.2 동력계 측정 시스템 28
• 3.1.3 연소특성 해석 시스템 30
• 3.1.4 배기가스 분석기 36
• 3.1.5 매연측정기 38
• 3.1.6 연료 소모량 측정기 40
• 3.2 실험방법 42
• 3.2.1 실험조건 42
• 3.2.2 실험 연료 구성 42
• 제 4 장 실험 결과 및 고찰 44
• 4.1 혼합연료 혼합비율에 따른 연소 및 배기특성 44
• 4.1.1 실린더 내 압력 45
• 4.1.2 최대 연소 압력 50
• 4.1.3 열발생률 52
• 4.1.4 최대 열발생률 56
• 4.1.5 제동연료소비율 58
• 4.1.6 제동열효율 60
• 4.1.7 CO 62
• 4.1.8 CO2 65
• 4.1.9 HC 67
• 4.1.10 NOx 68
• 4.1.11 PM 70
• 4.2 EGR 적용에 따른 연소 및 배기특성 72
• 4.2.1 실린더 내 압력 74
• 4.2.2 최대 연소 압력 77
• 4.2.3 열발생률 79
• 4.2.4 최대 열발생률 81
• 4.2.5 제동연료소비율 83
• 4.2.6 제동열효율 84
• 4.2.7 CO 86
• 4.2.8 CO2 87
• 4.2.9 HC 88
• 4.2.10 NOx 90
• 4.2.11 PM 91
• 제 5 장 결론 93
• 5.1 혼합연료 혼합비율에 따른 연소 및 배기특성 평가 93
• 5.1.1 연소특성 93
• 5.1.2 기관특성 93
• 5.1.3 배기특성 94
• 5.2 EGR 적용에 따른 연소 및 배기특성 평가 94
• 5.2.1 연소특성 94
• 5.2.2 기관특성 95
• 5.2.3 배기특성 95
• 참고문헌 96
• 감사의 글 102