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Lean ethanol-water/air mixtures have potential for reducing NOx and CO emissions in internal combustion engines. Igniting such mixtures is not possible with conventional ignition sources. An improved catalytic ignition source is being developed to aid in the combustion of aqueous ethanol. The operating principle is homogeneous charge compression ignition in a catalytic pre-chamber, followed by torch ignition of the main chamber. In this system, ignition timing can be adjusted by changing the length of the catalytic core element, the length of the pre-chamber, the diameter of the pre-chamber, and the electrical power supplied to the catalytic core element. A multi-zone energy balance model has been developed to understand ignition timing of ethanol-water mixtures. Model predictions agree with pressure versus crank angle data obtained from a 15 kW Yanmar diesel engine converted for catalytic operation on ethanol-water fuel.

Practical solar powered aircraft require an efficient energy storage system to store energy during the day for use at night. Hydrogen and oxygen, generated by electrolyzing water during the day and recombined at night to generate electricity, has a theoretical energy density of 3.73 kWh/kg. Harnessing this potential has been approached with a combination of a lightweight PEM electrolyzer and a lightweight PEM fuel cell with a new stack structure utilizing metallurgical bonding to assemble thin metal gas barriers with lightweight metal flow fields. This design minimizes size, weight, electrical resistance, and part count. This technology has been demonstrated to produce efficient and effective stacks.