Solar 2011: Applied tribology studies of an ethanol fueled otto engine for lawn mower application

The present project investigates the tribology and frictional losses of the contact surfaces on the reciprocating components in an ethanol fueled internal combustion engine while lubricated with mineral oil that has been contaminated with various percentages of ethanol. This paper outlines the process for measuring these frictional power losses. During start-up and cold run, bio-fuels condense on the cold cylinder walls and they are scrapped by the piston rings diluting the lubricating oil. As oil is degraded with fuel its viscosity decreases and the oil can no longer form a continuous lubricating film on the components of the valve train. This inherently increases the frictional forces on the valve train thus decreasing the engines efficiency. With proper instrumentation the instantaneous frictional forces can be mapped against the crank angle position at the different levels of oil contamination.