Experimental Investigation of SI Engine Performance Using Oxygenated Fuel

Abstract

The current experimental study aims to examine the effects of using oxygenates as a replacement of lead additives in gasoline on performance of a typical SI engine. The tested oxygenates are MTBE, methanol, and ethanol. These oxygenates were blended with a base unleaded fuel in three ratios (10, 15, and 20 vol.%). The engine maximum output and thermal efficiency were evaluated at a variety of engine operating conditions using an engine dynamometer set-up. The results of the oxygenated blends were compared to those of the base fuel and of a leaded fuel prepared by adding TEL to the base. When compared to the base and leaded fuels, the oxygenated blends improved the engine brake thermal efficiency. The leaded fuel performed better than the oxygenated blends in terms of the maximum output of the engine except in the case of 20 vol.% methanol and 15 vol.% ethanol blends. Overall, the methanol blends performed better than the other oxygenated blends in terms of engine output and thermal efficiency.

Effects of ethanol, ethyl-tert-butyl ether and dimethyl-carbonate blends with gasoline on SI engine

“…The results showed that blending unleaded gasoline with ethanol increased the brake power, torque, volumetric and brake thermal efficiencies and fuel consumption, while it decreased the brake specific fuel consumption and equivalence air-fuel ratio. Al-Farayedhi et al [46] showed that MTBE blends up to 20% volume in gasoline having a significant increase in brake thermal efficiency with respect to the base fuel at low speeds. This improvement was attributed to a considerable increase in the advanced maximum brake torque (MBT) attributed also to the improvement in anti-knock behavior, which allows more advanced MBT timing and thus higher output.…”

Characterisation of flame development with ethanol, butanol, iso-octane, gasoline and methane in a direct-injection spark-ignition engine

“…Combustion studies with ethanol in SI engines have been carried out by [2][3][4][5][6][7], focusing on performance characteristics, while others [8][9][10][11] have concentrated on engine emission measurements; most of these were done on Port Fuel Injection (PFI) engines. Very few studies have been conducted in latest technology Direct Injection Spark-Ignition (DISI) engines that are typically very sensitive to fuel properties; more to the point, in some of those studies, certain trends illustrate great diversity.…”

An Analysis of the Combustion Behavior of Ethanol, Butanol,Iso-Octane, Gasoline, and Methane in a Direct-Injection Spark-Ignition Research Engine

“…For example the studies of Brinkman (1981), , Davis and Heil (2000), Al-Farayedhi et al (2004), Nakata et al (2006), andTopgül et al (2006) focused on performance characteristics, while the works of Guerrieri et al (1995), , Sandiquist et al (2001), and Martinez and Ganji (2006) on exhaust emission measurements. Similarly, the combustion of butanol=gasoline blends with PFI was investigated by Alasfour (1997) and Swaja and Naber (2010) in single-cylinder research engines.…”