Combustion and performance characteristics of SI engine with bioethanol blended fuels

Abstract

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).