Impact of Various Exhaust Gas Recirculation  Ratio and Engine Operating Conditions on Emissions Characteristics and Engine Performance in Diesel Engine Fuelled by Diesel-Ethanol Blends

IJEP 43(6): 531-537 : Vol. 43 Issue. 6 (June 2023)

Mohammed A. Fayad1, Ahmed Q. Salam2, Louay A. Mahdi1, Sanaa A. Hafad1 and Miqdam T. Chaichan1*

1. University of Technology, Energy and Renewable Energies Technology Center, Baghdad, Iraq
2. University of Technology, Environment Research Centre, Baghdad, Iraq


Lower exhaust emissions and better engine performance can be reached by using exhaust gas recirculation (EGR) and alternative fuels. In this study, the effects of various conditions of injection timings (IT) and engine speeds with EGR on engine performance and NOx concentration fueling with alcohol fuels were investigated. According to the results of IT, it is clear that the brake power increased by 14, 9.23 and 5.6% with advanced IT for E10 and diesel fuel and different EGR ratios 10, 20 and 30%, respectively. In addition, the E10 blend produces high brake power in comparison with diesel for different EGR ratios. The BSFC decreased with advanced injection timings, while increased by 15.6%, 18.6% and 26.4% with increasing EGR ratios. The NOx concentration increased with advanced IT, meanwhile decreased with high ratio of EGR (10.2%, 21.3% and 29.7%). In case of engine speeds, the results showed that the brake power increased with engine speed between 1500 to 2250 rpm, especially with E10 blend compared with diesel. The same trend of brake power was found for various EGR ratios. The BSFC increased from the effects of various engine speeds and EGR ratios. The NOx emissions decreased from the combined effects of engine speeds and EGR for E10 and diesel.


Brake power, Ethanol, Diesel engine, Exhaust gas recirculation, NOx emissions, Engine speed


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