Abstract
A jet ignition method by hydrogen flame jet is proposed to control the combustion of lean mixtures. Hydrogen flame jet is supplied from the cavity whose volume is less than one percent of the main chamber volume through the nozzle. It is worried that the heat loss of the jet ignition method becomes bigger than that of conventional ignition, because this method creates strong and high temperature flame jet. Especially at the nozzle, the heat flux might become bigger than other place. So the heat flux at the nozzle were measured and the relation between the jet velocity and heat flux were shown. The faster the flame jet is, the bigger the heat flux at the nozzle is. And the heat flux increases with the temperature of the jet. The maximum heat flux is proportional to the velocity and the temperature of the flame jet.
