The rapid consumption of fossil fuels, ever rising energy demand, and rigorous emission norms have been attracting the attention of researchers toward clean renewable fuels such as alcohol-based fuels. Higher chain alcohol fuels are attractive alternative fuels for use in diesel engine. A higher chain alcohol (butanol, pentanol, etc.,) has better blending properties, higher calorific value, and higher cetane number than the lower chain alcohol. Alcohol fuels can be produced from the biomass. Therefore, it is important to examine the fuel, as well as its blends with diesel fuel in diesel engine for the engine characteristics. The present paper aims at studying the performance characteristics of a DI-CI engine using butanol/diesel (B/D) blends with and without exhaust gas recirculation (EGR). Experiments were performed on a single cylinder CI engine with two different B/D blends (20% and 40% by volume of butanol in the mixture—denoted as a Bu20 and Bu40), with different EGR rates (0%–30% in steps of 10%). The experimental results showed that the brake thermal efficiency (BTE) improved by 1.1% and 1.25% for Bu20 and Bu40 blends in comparison with Bu00. Nitrogen oxides (NOx) emissions reduced by 7.9%, 12.9% for Bu20 and Bu40 blends compared Bu00 respectively. Similarly, the soot emission decreased by 18% and 40.9% for Bu20 and Bu40 compared to Bu00. With the use of EGR, the NOx emissions significantly decreased. At 30% of EGR rate, the NOx emission reduced by 53.9%, 60.2%, and 67% for Bu00, Bu20, and Bu40, respectively. The soot emissions increased slightly at lower EGR rates of 0% to 20%. However, the soot emissions increased drastically at higher EGR rates for all the B/D blends. It is concluded that a combination of higher fraction of B/D blends along with a small EGR rate, can achieve lower emissions (soot and NOx) with a small penalty on the engine performance.

中文翻译：

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废气再循环对以丁醇/柴油混合物为燃料的 DI-CI 发动机性能和排放特性的影响

化石燃料的快速消耗、不断增长的能源需求和严格的排放标准已经吸引了研究人员对清洁可再生燃料（如酒精基燃料）的关注。高链醇燃料是用于柴油发动机的有吸引力的替代燃料。与低链醇相比，高链醇（丁醇、戊醇等）具有更好的混合性能、更高的热值和更高的十六烷值。可以从生物质中生产酒精燃料。因此，重要的是检查燃料，以及它与柴油发动机中柴油的混合物，以获得发动机特性。本论文旨在研究使用丁醇/柴油 (B/D) 混合物和无废气再循环 (EGR) 的 DI-CI 发动机的性能特征。在单缸 CI 发动机上进行了实验，该发动机具有两种不同的 B/D 混合物（混合物中丁醇体积的 20% 和 40%，表示为 Bu20 和 Bu40），具有不同的 EGR 率（0%–30% 分步10%）。实验结果表明，与 Bu00 相比，Bu20 和 Bu40 混合物的制动热效率 (BTE) 分别提高了 1.1% 和 1.25%。与 Bu00 相比，Bu20 和 Bu40 混合物的氮氧化物 (NOx) 排放量分别减少了 7.9% 和 12.9%。类似地，与 Bu00 相比，Bu20 和 Bu40 的烟尘排放量减少了 18% 和 40.9%。随着 EGR 的使用，NOx 排放量显着降低。在30%的EGR率下，Bu00、Bu20和Bu40的NOx排放量分别减少了53.9%、60.2%和67%。在 0% 到 20% 的较低 EGR 率下，烟尘排放略有增加。然而，所有 B/D 混合物的烟尘排放量在较高的 EGR 率下急剧增加。得出的结论是，较高比例的 B/D 混合物与较小的 EGR 率相结合，可以实现较低的排放（烟尘和 NOx），同时对发动机性能的影响较小。