Coal and biomass co-combustion process characterization using frequency analysis of flame flicker signals

The paper presents the application of frequency analysis of time series for diagnostic purposes of biomass and coal co-combustion process in laboratory scale. The analysed time series were generated as sequences of individual image pixels of known coordinates in video recordings that were captured during combustion experiments. The resulting spatial distribution of the dominant frequency and frequency centroid were analysed for several biomass co-combustion trials where thermal power and excess air coefficient were adjusted independently.