The combustion characteristics of single-cylinder spark-ignition (SI) engines with bioethanol blended fuels have been investigated experimentally. It is known that bioethanol (alcohol-based fuel) offers a range of advantages to be considered as a fuel for SI engines. This advantage range from its renewability to comparable fuel properties to conventional hydrocarbon fuels. Moreover, bioethanol can be produced from agricultural and municipal waste. The environmental benefits of bioethanol include its low contamination of atmosphere and reducing the dependency on conventional (eg, gasoline) fuel for the automotive sector. Analyses have been carried out to show the influence of bioethanol blended fuels (from 10% by vol. to 80% by vol.) on combustion and engine performance characteristics. Furthermore, the investigation is carried out for different blends and across different engine speeds including cycle-to-cycle variation analysis. Here pure gasoline (which already contains 10% by vol. ethanol) has been taken as a reference case. The apparent heat release rate has been computed using in-cylinder pressure. There is a significant increase in heat combustion with the increase in bioethanol contained in the fuel and maximum heat combustion is observed with a 60% bioethanol blend at higher engine speed. The fuel consumption increases with the increase in bioethanol percentage when compared with the reference case. Bioethanol addition to gasoline increases the in-cylinder peak pressure during combustion and overall volumetric efficiency. The results suggest that the E20 case shows a favorable choice and can be used over the E10 case for the studied engine without making any adjustments to the engine parameters (or engine control unit).

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生物乙醇混合燃料 SI 发动机的燃烧和性能特征

已经通过实验研究了使用生物乙醇混合燃料的单缸火花点火 (SI) 发动机的燃烧特性。众所周知，生物乙醇（酒精基燃料）具有一系列优势，被视为 SI 发动机的燃料。这种优势范围从其可再生性到与传统碳氢化合物燃料相当的燃料特性。此外，生物乙醇可以从农业和城市废物中生产。生物乙醇的环境效益包括其对大气的低污染和减少汽车行业对传统（例如汽油）燃料的依赖。已进行分析以显示生物乙醇混合燃料（从 10% 到 80% 体积）对燃烧和发动机性能特征的影响。此外，调查是针对不同的混合物和不同的发动机速度进行的，包括周期到周期的变化分析。这里以纯汽油（按体积计已经含有 10% 的乙醇）作为参考案例。已使用缸内压力计算表观热释放率。随着燃料中所含生物乙醇的增加，热燃烧显着增加，并且在较高发动机转速下观察到 60% 生物乙醇混合物的最大热燃烧。与参考案例相比，燃料消耗随着生物乙醇百分比的增加而增加。在汽油中添加生物乙醇会增加燃烧过程中的缸内峰值压力和整体容积效率。