To Study the Performance and Emissions Characteristics of Butanol Blended Gasoline Fuel Single Cylinder Spark Ignition Engine

Abstract

As our country has vast resources including molasses, bagasse, rice husk and wheat husk for production of butanol, utilization of butanol in spark ignition engine will enhance sustainability of energy sector. Butanol is a carbon neutral fuel and octane booster of gasoline. This study is aimed at study of performance and emission characteristics of a spark ignition engine for different butanol-gasoline blends. In the first phase, experimental work was conducted on the spark ignition engine with butanol which volume in gasoline was varied from 10% to 30%. The compression ratio of the engine was maintained as 6.5:1. CO and HC emissions decreased with increase the butanol content in gasoline. This is due to increase in oxygen %age in the fuel. However, NOx emission increased with higher percentage of butanol in gasoline blend. It is observed from this experimental study that latent heat of vaporization of butanol dominates the NOx at lower load resulting to lower NOx where as high temperature due to oxygen content of butanol influences at higher load that results in higher NOx emission. In the second phase, in order to improve the performance and emission reduction of the engine, its compression ratio was increased from 6.5:1 to 8.7:1 by modification of the engine cylinder head. The results indicate the beneficial of the higher compression ratio in terms of performance and all emissions except NOx emission. HC emissions decreased drastically from 115 ppm with B0 to 74 ppm with B20 and CO decreases from 7.62% for B0 to 4.4% for B20.NOx emission is lesser at lower load and conversely it is higher at higher load. It is vary from 107 ppm with zero load to 1013 ppm with B30 at 1500W load. The optimum value of butanol percentage in gasoline is chosen as based on NOx emission.