An Investigation Of Emission Characteristics Of A Turbocharged Common Rail Direct Injection (CRDI) Diesel Engine Fuelled With Diesel-Butanol Blends

This paper investigate and compare the impacts of biodiesel/n-butanol blends on the engine exhaust gas emissions in a turbocharged CRDI in-line 4 cylinder, 4-stroke diesel engine. B5 biodiesel, nB5 (5% biodiesel, 95% diesel) was used as the base fuel and blended with nBU10 (10% n-butanol, 90% B5 biodiesel) by volume respectively. The properties of this blended fuel was reviewed based on calorific value, viscosity, density, latent heat value and the advantages and disadvantages of blended fuel was determined. Exhaust gas emissions were measured in terms of CO, O2, NOx and CO2 by using Kane Gas Analyzer. The test results shows CO emission levels were observed to be reduced at higher loads for the blended fuel due to complete combustion which increase the amount of O2 to the combustion process. At low loads, high presence of O2 were observed due to lean fuel mixture or not enough fuel in combustion chamber. NOx emission with nBU10 and nB5 were found to be comparable at low loads due to lower calorific value and slightly increased at high load with increased butanol percentage in the blend compared to nB5. Lower CO2 emission were found with increased in engine loads due to complete combustion and lower presence of O2 in combustion chamber. However, using an alcohol as an additive to neat diesel fuel is a great approach for automotive industry which can produce less emission pollutants but total costs for biodiesel alcohol blends is higher than conventional fossil fuels.

Keywords: n-butanol, biodiesel, Diesel engine, Engine loads, NOx