Experimental comparative study on combustion, performance and emissions characteristics of ethanol-gasoline blends in a two stroke uniflow gasoline engine

Ethanol, an alternative fuels based on alcohol for spark ignition engines, can be used by mixing with gasoline at the proper ratios, and which reducing exhaust emissions by an increase in oxygen content. Although there are many studies conducted on the use of ethanol in internal combustion engines, no studies have been conducted on the use of ethanol in two-stroke uniflow gasoline engines so far. In this experimental study, performance, emission and combustion characteristics of ethanol/gasoline blends (range of ethanol 10% v-50% v) were examined in a two-stroke uniflow gasoline engine at 1800 1/min and full load. In cylinder pressures, heat release rates, mass fraction burnt, engine torque, break specific fuel consumptions, delivery ratio, scavenging efficiency, carbon monoxide (CO), hydrocarbon (HC), carbon dioxide (CO2) and nitrogen oxides (NOx) emissions were investigated. The combustion phasing was advanced after adding ethanol due to the higher burning velocity. Delivery ratio and scavenging efficiency have increased due to the faster evaporation of ethanol than gasoline. Break thermal efficiency (BTE) decreased because of the decreased net work, and break specific fuel consumption (BSFC) increased because ethanol had lower heating value (LHV) than gasoline. CO, HC, CO2 and NOx emissions decreased with the increase in the ethanol content in gasoline.

Automated summary

This experimental study investigated the performance, emission, and combustion characteristics of ethanol/gasoline blends in a two-stroke uniflow gasoline engine. The results showed that the addition of ethanol increased the burning velocity, delivery ratio, and scavenging efficiency, but decreased the break thermal efficiency and increased the break specific fuel consumption. The emissions of CO, HC, CO2, and NOx decreased with the increase in ethanol content.