Effect of Low Pressure on Flame Propagation of Hydrogen-Kerosene-Air Mixture

Hydrogen may play an important role in gas turbine engines for achieving carbon neutrality and performing high-altitude missions. Hydrogen influence on the flame speed of aviation kerosene at low pressures was investigated using a constant-volume bomb. The laminar flame speed of aviation kerosene at atmospheric pressure exhibited a linear relationship with increasing hydrogen mass fraction, with a more pronounced promoting effect under fuel-rich conditions. Hydrogen promotion effects on normalized kerosene laminar flame speed are weaker at low pressures than those at atmospheric pressures. The addition of hydrogen and low pressure suppresses flame instability of aviation kerosene especially under fuel-rich conditions, thereby reducing the promoting effect of turbulence on fuel-rich flame propagation. A scaling law that accounted for the influence of flame stability was successfully constructed to characterize the turbulent flame speed of hydrogen-rich aviation kerosene under different conditions.