Flame rectification (original) (raw)

Flame rectification is a phenomenon in which a flame can act as an electrical rectifier. The effect is commonly described as being caused by the greater mobility of electrons relative to that of positive ions within the flame, and the asymmetric nature of the electrodes used to detect the phenomenon. This effect is used by rectification flame sensors to detect the presence of flame. The rectifying effect of the flame on an AC voltage allows the presence of flame to be distinguished from a resistive leakage path.