Effect of flow and reactive environment on acoustic characteristic of H2–CH4 inverse diffusion flame

Abstract

The acoustic characteristic of swirled and non-swirled turbulent inverse diffusion flame (IDF) for hydrogen-methane fuel is experimentally investigated with variation in Reynolds numbers (Reair) and equivalence ratios (Φ). For maintaining adequate working environment, noise characterization of hydrogen-methane fuel IDF is essential. Comparison of sound level indicates significant alteration in acoustic characteristics with change in Reair, Φ and swirl. The swirling IDF is noisier than the non-swirling IDF at the same Reair and Φ. The sound level increases by 9.9% for swirling and 10.2% for non-swirling IDFs with a surge in Reair. The variation of Φ (0.6 ≤ Φ ≤ 1.4) indicates that the noise of IDF with swirl is higher (an increase of 13.14%) than non-swirling IDF (an increase of 1.43%). Shearing of flow induced by swirl dominates sound generation. For swirling IDF, the rise in sound level is 3.67% when methane is blended with H2 from 0% to 10%.