Laminar Burning Velocity Measurement of NH₃/H₂/CH₄ Fuel Blends at Elevated Temperature and Pressure

The need for exploration of carbon-free fuels has increased the research into combustion characteristics of carbon-free fuels. Ammonia has potentially gained attention as it acts as a hydrogen energy carrier with high volumetric energy density. The present study focuses on measurement of laminar burning velocity of NH3/H2/CH4-air mixtures using externally heated diverging channel technique at high pressure (0.1-0.2 MPa) and temperatures (300–750 K). NH3 concentration is varied from 0-30% by volume in fuel. Laminar burning velocity increases with mixture temperature and decreases with NH3 concentration and pressure. Temperature exponent was observed to increase with the pressure. Predictions of Okafor and Li models shows good consistency with the present work. A decrement in the burning velocity was observed due to higher consumption of O and H radicals for the formation of HNO radicals.