Characterization of Lubricant Degeneration and Component Deterioration on Diesel Engine Fueling with Straight Plant Oil

Straight Plant Oils (SPOs) are promising alternatives to diesel fuel in some particular applications, e.g. electrification in remote areas and sustainable modernization of artisan fishing vessels. Moderate commercialization of SPOs is yet to be realized due to lack of critical information on engine durability, lubricant degeneration, and effective methods to offset the adverse effect of directly using SPOs on diesel engines. In this paper, the experimental study evaluates the long term impacts of crude Jatropha oil (JO) on a small diesel engine generator through 300 hour durability tests. The testing results demonstrate the evolution of gaseous emissions, the trace metal element variations in lubricant, and the carbon deposit formation on engine components. The associated fuel spray experiments in the controlled environment further reveal JO atomization patterns and provide important evidence to interpret why JO has greater influence on engine durability than diesel.