Combustion Characteristics of a Premixed Test Combustor for a Hydrogen-Fueled Micro-Gas Turbine

Lean premixed combustion may reduce NOx emission of gas turbines. On the basis of this concept, a micro gas turbine test combustor using a lean premixed swirling hydrogen flame has been developed. To attain experimental understanding of combustion characteristics of the combustor, stability limits, temperature and flow fields, and exhaust emissions were measured. The measurements showed that a stable swirling hydrogen flame attached to a flame holder was formed even in high-velocity premixed streams at low equivalence ratios. The combustor had the high rate of volumetric heat release of 2.5×103 W/(m3·Pa), and attained high combustion efficiencies of over 99.98%. Hydrogen combustion in the combustor resulted in extremely low NO-x emission levels of under 1 ppm, in comparison with a hydrogen-burning diffusion combustor.