Dept. of Mechanical Engineering, Syiah Kuala University, Aceh, 23111, Indonesia

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Abstract: Cerbera odollam is a plant species commonly found in coastal areas, especially in Aceh, Indonesia. Based on traditional processes, carbera odollam seeds are potentially capable of producing oil. The objective of this research is to examine the effects of specific fuel consumption, power generation and the thermal efficiency on diesel engine performance based on different ratios of diesel and Cerbera odollam seeds oil blends (B-0, B-10, B-20 and B-30) under high speed rotation of the diesel engine. The result showed that, at relatively low rotational speeds of the engine (2000 rpm to 2500 rpm), there are no significant effects on fuel consumption (for each type of fuel). In addition, the experimental results revealed that, when the rotational speed exceeds 2500 rpm, the specific fuel consumption significantly increases. The power generation increases when the engine rotation increases. It was found that the diesel and Cerbera odollam seeds oil blends are superior at relatively lower rotational speed, while the pure diesel fuel excels at a rotational speed of 3500 rpm. In addition, the thermal efficiency of diesel and blended diesel decreases when the engine rotation increases.

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