Chidambaranathan Bibin, Kumarasami Devan Ponnusamy, Raghavan Sheeja, Sundaram Madhu
Department of Mechanical Engineering, R.M.K. College of Engineering and Technology, Chennai, India.
Department of Computer Science and Engineering, Easwari Engineering College, Chennai, India.
Environ Sci Pollut Res Int. 2023 May;30(22):61190-61203. doi: 10.1007/s11356-022-20463-z. Epub 2022 May 3.
Major energy production all over the world depends on fossil fuels. Recent research on alternative energy sources has raised major concerns about environmental impacts, future availability, and cost. Pollution from diesel engines also affects the environment negatively. As a result, there is a worldwide concern about reducing the pollutants emitted by diesel engines. In comparison to diesel fuel, biodiesel combustion produces reduced carbon monoxide (CO) and unburned hydrocarbon (UHC) emissions but higher nitrogen oxide (NO) emissions. The current study aims to investigate the thermal and chemical effects of exhaust gas recirculation (EGR) on the features of a diesel engine for environmental sustainability. The punnai oil was produced from kernels of punnai seeds and transesterified in two phases using alcohol with the existence of a catalyst. The higher viscosity of punnai oil biodiesel is diluted by mixing it with diesel fuel. Our previous investigation indicated that neat punnai oil biodiesel is a potential fuel; however, the findings showed that the addition of diesel is necessary to obtain acceptable engine performance. In this study, punnai oil biodiesel was mixed at a rate of 20% with diesel (B20) and run in a diesel engine with varied EGR rates under five different engine loads. This combined impact enhanced the maximum heat release rate (HRR) and maximum combustion pressure, according to the findings. The premixed burning fractions were commonly higher at all engine loads, whereas the diffusion combustion fractions were lower. When the centre of the HRR changed toward the top dead centre (TDC), combustion durations remained rather constant. The experimental results revealed the B20 blend at a 10% EGR flow rate produced 6.57% lower BTE, 37.04% higher BSEC, 2.47% higher EGT, 5.13% lower CO, 31.11% higher CO, 3.13% higher UHC, 8.36% lower NO, and 4% higher smoke opacity when compared with diesel in a standard diesel engine.
全世界的主要能源生产都依赖化石燃料。近期对替代能源的研究引发了人们对环境影响、未来供应及成本的重大担忧。柴油发动机产生的污染也对环境有负面影响。因此，全球都在关注减少柴油发动机排放的污染物。与柴油相比，生物柴油燃烧产生的一氧化碳（CO）和未燃烧碳氢化合物（UHC）排放量减少，但氮氧化物（NO）排放量更高。当前的研究旨在探究废气再循环（EGR）对柴油发动机特性的热效应和化学效应，以实现环境可持续性。番奈油由番奈种子的果仁制成，并在催化剂存在的情况下分两个阶段与酒精进行酯交换反应。番奈油生物柴油较高的粘度通过与柴油混合来稀释。我们之前的研究表明，纯番奈油生物柴油是一种有潜力的燃料；然而，研究结果显示，添加柴油对于获得可接受的发动机性能是必要的。在本研究中，番奈油生物柴油以20%的比例与柴油混合（B20），并在一台柴油发动机中运行，在五种不同的发动机负荷下采用不同的EGR率。研究结果表明，这种综合影响提高了最大热释放率（HRR）和最大燃烧压力。在所有发动机负荷下，预混燃烧分数通常更高，而扩散燃烧分数更低。当HRR的中心朝着上止点（TDC）变化时，燃烧持续时间保持相当稳定。实验结果显示，在一台标准柴油发动机中，与柴油相比，EGR流量为10%时的B20混合燃料产生的制动热效率（BTE）低6.57%，制动比油耗（BSEC）高37.04%，排气温度（EGT）高2.47%，CO低5.13%，CO₂高31.11%，UHC高3.13%，NO低8.36%，烟度高4%。
