Forced reattachment evolution process of a lifted jet diffusion flame induced by repetitive D.C. Pulsed discharges

Electrically enhanced combustion by applying electric fields or plasmas has been demonstrated as a promising approach to the problem of flame instability occurred in lean combustion process. In this study, the lifted-flame forced reattachment process in a turbulent non-premixed propane jet induced by a repetitive D.C. pulsed discharges with a proposed electrode configuration have been experimentally investigated. A conditional particle image velocimetry (cond-PIV) measurement is used to analyze the detailed flame-flow interaction of complete reattachment process. The results show that the effect of pulsed discharge on flame stabilization is significant with increasing pulse repetition frequency (PRF). According to the time history of flame base height and variation of absolute flame speed with the axial location, it suggests that the corona discharge plays a key role in flame dynamic propagation process, leading to flame reattachment, as a result of the flame-edge propagation speed is augmented over 3 S_L.