THE EFFECT OF METHANOL BLENDED WITH GASOLINE ON THE PERFORMANCE AND VIBRATION OF SPARK IGNITION ENGINE

Abstract

This study is an experimental investigation of the effects of methanol addition to gasoline on the performance (brake power, brake specific fuel consumption), and emissions (carbon monoxide CO, hydrocarbons HC) of a spark ignition engine, engine vibration was also measured (Acceleration). The tests were carried out at constant throttle variable speed condition operating with standard and advanced spark timing (10˚ and 11˚ BTDC respectively) over the range of speed from 1500 to 2250 rpm and compression ratios CR=8 and 9 using various blends of methanol/gasoline 0% (M0), 5% (M5), 10% (M10), 15% (M15) and 20% (M20) methanol by volume. The experimental results showed that for standard spark timing, maximum power was obtained at M10 CR9 by increase of (18.29%) from M0. While for advanced spark timing, maximum power was obtained at M20 CR9 by an increase (18.27%) from M0. Advancing spark timing resulted in power increase by (13.4%) from standard spark timing. Optimum compression ratio for gasoline fuel was 8 while for methanol-gasoline blends was 9. Emissions of CO and HC were decreased significantly by using methanol as fuel additive and increasing methanol content in the fuel. M0 exhibited the lowest and most stable acceleration level at higher engine speed at CR8 (2000-2250 rpm). While for CR9, M5 generally showed the lowest acceleration values for lower and higher engine speeds. M15 fuel blend, showed maximum acceleration level compared to other fuel blends.