Characteristics of Ion Current Obtained from Low-Oxygen, High-Temperature Air Combustion

Abstract

An attempt has been made to examine the characteristics of ion current obtained from Low-Oxygen, High-Temperature Air Combustion. Non-luminous zone is seen in the upstream region and luminous zone is seen in the downstream region in low-oxygen, high-temperature air flame, while only the luminous region is seen in the high-temperature air flame. The sharp spike like signals are seen on the ion current obtained from the luminous zone of both high-temperature air and low-oxygen, high-temperature air flames. The spike like signal is not seen on the ion current obtained from the non-luminous zone of low-oxygen, high-temperature air flame. The ion current looks quite similar with that obtained from turbulent premixed flames in the reaction sheet regime. It implies that the local structure of low-oxygen, high-temperature air flame is not the flameless combustion but shmilar to that of turbulent premixed flames in the reaction sheet regime, in which the local reaction zone is separately defined from burnt and unburnt gases.