Performance Analysis of Iranian National Heavy-Duty Diesel Engine under RCCI Combustion Fueled with Landfill Gas and Diesel Fuel

Landfill gas is one of the most important constituents in greenhouse gas production, but, it could be easily eliminated by using it in an engine as an alternative to conventional fuels. Because, there are several concerns about the use of LFG as fuel, therefore, the present study seeks to analyze the performance of the Iranian heavy-duty diesel engine (D87) under RCCI combustion fueled with diesel fuel and LFG. The main objectives of this study are to overcome the limitations of using LFG in the D87 engine as an alternative fuel, improve the D87 engine combustion characteristics, and reduce engine emissions. For this purpose, the effects of four major influential input parameters on the D87 engine performance were evaluated, namely, the IVC temperature and pressure, the diesel fuel SOI timing, and the LFG/diesel fuel mass ratio. The DOE concept-Factorial method was employed to predict the appropriate ranges of the selected four crucial parameters that lead to the desired performance. The simulation results show that the desirable engine performance would be achieved for the IVC temperature between 350 and 400K, for the IVC pressure between 2.6 and 2.9 bar, for the diesel fuel SOI timing between -75 and -30o ATDC, and the LFG/diesel fuel mass ratio between 70/30 and 85/15. Although, the hydrocarbon fuel consumption can be reduced by more than 80% byG, the downfall is that the EURO VI level for NOx, CO, and UHC and also the EPA 2007 level for Formaldehyde cannot be met.