Chemiluminescence Measurements of Laminar Premixed Ethylene/Air Flame at Low Pressure

Abstract

Ethylene plays an important role in regenerative-cooling scramjet engine, but its combustion characteristics have not yet been studied thoroughly. This paper reports the design of a square flat flame burner used for chemiluminescence measurement technique and the concentration of OH* and CH* of laminar premixed ethylene/air flame at low pressure. An approach of obtaining quantitative concentration through both PLIF experiments and CHEMKIN simulations is proposed. Results show that the maximum concentration is about 10⁸ cm^-3 and increases with elevated pressure. Although the maximum concentration depends much on equivalence ratio and pressure, the ratio of the maximum CH*/OH* concentration is independent of pressure (10kPa∼50kPa). The results are prerequisite for employing chemiluminescence technique in ethylene combustion process.