Thesis Archive
Engine Performance and Exhaust Gas Emission of Stable Blends of Diesel- Coconut Oil Biodiesel- Ethanol (2013-2014)
Cindy Y. Cheng
Clairene N. Dy
Sarah Jane T. Ilano
Abstract:
-“Coconut methyl ester (CME) was used as an emulsifier for the diesel-ethanol blend to prevent phase separation. The stable blends of diesel-ethanol-CME were determined by Ardiyati (2012) and the engine performance and exhaust emission were already tested in an idle engine. This study which is a continuation of the work done by Ardiyati involved the determination of engine performance and exhaust emission of the stable blends at various engine loads. The effect of varying proportions of diesel, ethanol and coco methyl ester in the blends were determined and compared with the commercially available diesel. The electrical loads applied were 500W, 1000, and 1500W respectively. There was an overall improvement in the engine performance such as electrical fuel consumption, and electrical thermal efficiency using the blends as fuel at various loads as compared to the commercially available diesel. The improvement is due to the addition of CME, a cetane enhancer which compensated the loss in cetane number of the blend due to the addition of ethanol. The lower heating values of ethanol and CME than diesel caused the reduction of electrical specific fuel consumption (ESFC) of the blends. Ethanol and CME acted as an oxygenator to make the combustion more efficient. The exhaust emission in terms of CO, CO2, free O2, unburned hydrocarbon (HC) and smoke density of the blends as fuel were improved compared to the commercially available diesel, especially during high engine loads in which the air-fuel ratio is higher. There was a reduction in CO emission for the blends with lower diesel content and higher ethanol content. There was no significant change in nitrous oxide (NOx) emission during idle condition but it increased at higher engine loads. The presence of sulfur oxides (SOx) was also reduced. The improvement in engine performance and exhaust emission of the blends showed that these fuels could be used as substitutes for the conventional diesel fuel.”
Adviser:
Dr. Nathaniel P. Dugos
Dr. Susan A. Roces