Control of Combustion by Hydrogen Flame Jet Ignition in a Closed Chamber : (Heat Flux and NO_x)

Abstract

A hydrogen jet ignition method is proposed to control the combustion of lean mixtures. The hydrogen jet is supplied from the cavity whose volume is less than one percent of main chamber volume through a nozzle. The heat flux at the wall in the main chamber and the NO_x emission are measured. It is shown that the heat flux becomes smaller as the combustion duration is longer. On the contrary, the heat flux of hydrogen jet ignition is smaller than that of conventional ignition when the combustion durations are equal. The NO_x emission of hydrogen jet ignition is bigger than conventional ignition when the equivalence ratios are the same. The NO_x emission of very lean mixture whose combustion duration is reduced less than that of conventional ignition of stoichiometric one is smaller than that of conventional ignition of it. It is shown that the NO_x emission is reduced keeping the fast combustion duration by using hydrogen jet ignition method.