Influence of Higher Alcohols on the Combustion Pressure of Diesel Engine Operated with Rape Seed Oil

To replace diesel fuel in IC engines, one of the most used alternatives is rape seed oil. In this research rape seed oil has been blended with higher alcohols as the 1-butanol and 2-propanol in 10 or 20 vol% to reduce viscosity. We present our results investigating the effect of these blends on the combustion process and on the emission. We describe the measurement system and the calculation methods applied for evaluation. Results show that both blends have significant effect on the pollutant emission, but the concrete effect may differ from blend to blend. The smoke emission significantly decreases, but there is an increment in the CO and THC emissions. NOx emission slightly decreases in case of butanol, but increases in case of 2-propanol. Considering the combustion process, alcohol blends increase the intensity of the kinetic combustion, and decrease the length of the diffuse phase.