Analysis of the Effects of Pressure and Unmixedness on NOx Emissions in a Model Gas Turbine Combustor

Pressure effects on NOx emission in a gas turbine combustor are numerically investigated in the present study. Initially, fully premixed flame condition with air and fuel injection at the combustor inlet is examined. Increasing pressure leads to a 0.08% rise in flame temperature and a significant 30% increase in NOx emissions. Technically premixed flame condition is then conducted. NOx emissions rise from 1.3 to 3 bar but decline beyond 3 bar due to combined pressure and mixing effects. Applying the NOx emission calibration formula, which accounts for pressure-induced changes while eliminating mixing influence, reveals a direct link between increased pressure and higher NOx emissions.