Experimental Study on Performance, Emissions and Combustion Characteristics of PFI Spark Ignition Engine Fueled with E30 Equivalent Binary and Ternary GEM Blends

Abstract

This work presents the concept of ternary blends of gasoline, ethanol and methanol (GEM) in which stoichiometric air to fuel ratio is controlled to 13.2, same as that of conventional binary E30 (Gasoline 70% + Ethanol 30% (v/v)) fuel blend. The formulated E30 equivalent ternary blends have approximately the same energy density, lower heating value and octane number as target binary E30 blend such that they can be a drop-in alternative to it. The experimental work was performed to investigate the performance, emission and combustion characteristics of PFI SI engine using E30 equivalent GEM blends. The engine tests were conducted at constant load while varying the engine speed from 1700 to 3300 rpm by varying the throttle position. The performance, emission and combustion results were measured and compared with pure gasoline. The results show that formulated GEM blends have similar brake thermal efficiency, in-cylinder pressure and net heat release as binary E30 blend and are improved when compared to pure gasoline. It is also noted that exhaust emissions such as Carbon monoxide (CO), unburned hydrocarbons (HC) show decreased values and increase in Nitrogen Oxide (NOx) for blended fuels compared to pure gasoline due to oxygenated nature of alcohol fuels.