A novel radical jet generator (RJG) was developed, whose purpose it is to supply concentrated, relatively low temperature radicals that penetrate into a flammable stream of reactants and trigger or modify a combustion process. The RJG is driven by a plasma whose power is only a fraction of a percent of the total power released in the combustor. In this approach, the plasma induces an incomplete combustion process in a small duct carrying a rich mixture of fuel and air. Results obtained using the developed RJG show that a jet, which consists of partially burnt reactants, some products and is, apparently, rich in radicals produced by the incomplete combustion process triggers extremely steady combustion in a fast moving combustible mixture whose flow rate far exceeds that of the RJG. Importantly, the results show that the jet, rich with radicals, that emerges from the RJG cavity at a temperature well below traditional ignition can ignite a fast moving stream of combustible mixture. Moreover, when injected normal to the main flow, this jet ignites the main stream at a location relatively far from the entrance point of the jet. This makes it possible to keep the combustion process away from solid walls while at the same time eliminating the need for solid flame holders. This in turn, provides an augmenter with reduced I.R signature. Finally, the results show a drastic effect of the RJG upon the flame dynamics in general and combustion instabilities in particular. Flames which displayed large, periodic pressure oscillations became completely stable when the plasma in the RJG was turned on. This suggests a novel use of the RJG to inhibit instabilities in combustors.

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