Effect of Variation of Compression Ratio and Injection Pressure on Performance and Emission Characteristics of Ci Engine Using Various Alternative Fuels: a Review

Compression Ignition (CI) engines are widely used for transportation, agriculture, power generation and industrial applications. The conventional fuel for CI engine is petro diesel. Among the countries in the world, India is one of the largest consumers of petro diesel fuel. Indian economy is very much dependant on the consumption of petro diesel. Brake thermal efficiency, brake specific fuel consumption, emissions of CO, HC, CO2, NOx and smoke opacity are the major considerations with the performance and emission characteristics of CI engine. Injection pressure, compression ratio, injection timing, and fuel quality are parameters which affect the engine performance and emissions. For optimizing the consumption of diesel, use of blends of alternative fuels with diesel has been promoted and study of engine parameters with the use of these fuels have been presented by many researchers across the world. In this review paper, effect of variation of compression ratio and injection pressure on the performance and emission characteristics of CI engine using different alternative fuels has been studied and compared with the diesel fuel. Alternative fuels under study were ethanol, methanol, Jatropha Methyl Ester, Mahua Methyl Ester and Pangomia Methyl Ester in 20% blending with diesel fuel. In this study, compression ratios 16.5, 17.5, 18.5 and injection pressures 200, 225, 250 bar have been considered for review. Review reveals that performance characteristics have been improved for all test fuels with increasing compression ratio and injection pressure at full load conditions. On the other hand emission characteristics of engines have been affected as NOx increase and HC and CO decrease with increase in compression ratio and injection pressure for all test fuels.