Combustion with mixed enrichment of oxygen and hydrogen in lean regime

摘要

A low global richness of combustion is interesting from an ecological and economic point of view as it helps to limit fuel consumption. In fact, the consequences of the combustion in poor mode are the appearance of local or global flame extinctions, energy loss by radiation and change in flame structure. The flammability limits of the diffusion methane flame can be resolved by the enrichment of the combustion air with oxygen or the use of the pure oxygen as oxidant as well as the addition to hydrogen in natural gas. Moreover, the use of oxygen and hydrogen as previously mentioned allow working in low ranges of richness while maintaining good flame stability. For a constant burner power of 15 kW, the reduction of the richness involves an increase in the oxidizer flow rate injected into the combustion reaction. In this present study, the variation of the richness, the fuel enrichment with hydrogen and the oxidant enrichment with oxygen are shown as major parameters where they have direct influences on the flow dynamic, the flame structure and the pollutant emissions.