Numerical Investigation on the Effects of LPG-biogas blends on Engine Combustion and Emission

摘要

A quasi-dimensional spark ignition (SI) engine cycle model is used to predict the combustion and exhaust emissions of a gas engine driven generator for the cases of using biogas and liquefied petroleum gas (LPG)-biogas blends. Two different thermodynamic regions consisting of unburned gases and burned gases that are separated by the flame front are considered. Liquefied petroleum gas (0%, 5% and 15%) was added to the biogas and was simulated as the fuel of SI engine. The results suggest that: There is an increase in cylinder pressure and temperature with the addition of LPG in biogas. Comparisons show that if LPG fueled SI engines are operated at the same conditions with those of biogas fueled SI engine, the mole fractions of CO and NO predicted for LPG-biogas blends are higher than those for biogas and the effects on the engine structural elements are not promising.