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Emmanuel Wornyoh — 2005-06 Fellow

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Fuel cell technology offers a clean and sustainable energy alternative to conventional petroleum-based technology, which could avert an international energy crisis. However, existing technologies needed to enable working mobile fuel cell systems cannot meet the stringent operational requirements that are necessary for successful large-scale implementation. For example, fuel cell air compressor/expander systems must operate under extreme-speeds (~75 m/s) and their efficiency and reliability will depend on effective lubrication of critical mating components. Moreover, conventional oil lubricants cannot be used without the danger of contaminating mobile fuel cell stacks. They would also not be lubricious in stationary high-temperature fuel cell applications. Fortunately, the excellent high-temperature tribological characteristics of solid/powder lubricants can be tapped, for lubricating critical mating components. Applied in the appropriate manner, these powders have demonstrated self-replenishing and self-repairing lubrication capabilities.

At the Particulate Flow and Tribology Laboratory (PFTL) at Carnegie Mellon University, a control volume fractional coverage (CVFC) model has been developed to predict the tribological behavior in a specially built, extreme speed and load in-house tribometer. These tools will be used to: (1) develop and evaluate low-friction and wear-resistant powder films on tribosurfaces used in air compressor/expanders for fuel cells; (2) develop the self-repairing, self-replenishing lubrication mechanism for ultra-high-speed tribosystem; and (3) test an environmentally benign lubricant for petroleum-free, energy conserving solid/powder lubrication. A filter system will also be researched to prevent the contamination of fuel cell stacks by foreign particles.