Structure and thermoacoustic instability of turbulent swirling lean premixed methane/hydrogen/air flames in a model combustor
The structure and thermoacoustic instability (TI) of premixed CH4/H2/air swirling flames were experimentally investigated for a range of hydrogen fraction (ηH2) up to 80% under different equivalence ratio (Φ) and swirl number (S) conditions. It is shown that the onset of TI is enhanced when increasing either ηH2, S, or Φ. The dominant frequency of TI increases dramatically with ηH2. The higher dom