Special gear was needed to form and ignite the droplet, then scientists had to figure out how best to observe the fireball so they could extract meaningful data that could be applied here on Earth. N.J. The work started with Dr. S. Kumagai of the University of Tokyo in the 1950s. In a prelude to drop towers now used by NASA for various experiments, Kumagai built an apparatus that could form a droplet that would burn during a 2-second fall. But it rarely worked because of the difficulty of timing the release, and because the droplet often was disturbed by the act of releasing it from the injection needle. So much effort is being expended in studying droplet combustion because society is placing much greater demands on itself in transportation.
More vehicles means more fuel is needed, and more emissions are produced.
And that demands higher efficiency as well as reduced emissions from each vehicle. In the 1940s, it was easier to squeeze a 4 percent improvement out of automobile combustion, explained Dr. Fred Dryer, a DCE co-investigator at Princeton University. Extra efficiency is harder to squeeze out of today's advanced engines, and the designer must also cope with laws that limit or ban emissions of nitrogen oxides, hydrocarbons, particles, and other exhaust products. The complexity of that problem is just incredible. Therefore, we need sophisticated computer tools to help guide engineering development.