Heat Flux at a Wall of Combustion Chamber in Hydrogen Flame Jet Ignition

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 the velocity of the flame jet is very fast and the temperature of it is very high. And the formation of the hot spot due to the flame jet, which might damage the wall, is worried. So the heat flux at the walls of the main chamber and the cavity were measured in the previous reports. In this report, the heat flux at the nozzle is investigated. The heat flux at the nozzle becomes bigger than that of other locations. The nozzle diameter affects the heat flux. The smaller the nozzle diameter is, the bigger the heat flux at the nozzle is. When hydrogen oxygen mixture is used in the cavity, the heat flux becomes very big.