Iraqi gasoline performance at low engine speeds

Abstract

Four grades of gasoline fuel – obtained from Iraqi oil refineries – are used in this research to investigate their performance in spark-ignition (SI) engines. These grades are RON 77, RON 82, RON 87, and RON 93. We used a four-stroke, four-cylinder SI engine laboratory rig to conduct the experiments and calculate the engine performance for each gasoline grade. We compared the experimental results with the predicted numerical simulations carried out using a well-known commercial software called Lotus Engine Simulation (LES). The numerical results obtained using LES show good agreement with experimental findings. A higher gasoline grade shows better engine performance than lower grades owing to its superior quality and purity, better combustion characteristics and performance, and lower amount of gasoline inclusions. Gasoline fuel RON 93 provided the best engine performance in comparison to the remaining grades. The variation between the numerical and experimental results in all tested conditions was below 3%.

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