Flames augmented by Inductive Coupling of Electrical Energy

Abstract

IN recent years there have been a number of studies of flames augmented by the application of an electrical discharge. The purpose of some has been to increase the final flame temperature, and of others to obtain increased combustion intensity as well as elevated temperatures. Several useful techniques have been developed, each of which has its own particular advantages; these are magnetically rotated arcs¹, a.c. and d.c. arcs applied to turbulent flames^2,3 (sometimes seeded with easily ionized materials), and a system based on the rapid mixing of a plasma stream with jets of reactants⁴. An earlier attempt to use a radio frequency discharge was unsuccessful¹, because the discharge was very unstable in the presence of fuel. Our work, however, has shown that by seeding the reactants with an easily ionized material radio-frequency coupling can be achieved with certain advantages apart from the obvious ones; we find absence of electrode erosion, no electrode contamination of products and no electrode energy losses because no electrodes are immersed in the plasma.