Plasma-Assisted Combustor Dynamics Control at Realistic Gas Turbine Conditions

This study investigated the effectiveness of implementing a plasma discharge to improve combustor dynamics and flame stability. Specifically, a nano-second pulsed plasma discharge (NSPD) was applied to a premixed gaseous fuel/air dump combustor for mitigation of dynamic combustion instabilities with a minimal NOX penalty. As a result, a significant reduction of pressure fluctuation level (2X to 4X) was observed at realistic low-power conditions of aero-engine combustors. The plasma power required for the reduction increased with increasing combustor inlet velocity and pressure. The change of fuel from methane to propane required significantly (2X) higher plasma power to achieve a similar noise reduction. The lean blowout limit was significantly extended due to the plasma; however, substantial incomplete combustion occurred in the extended regime. The incremental NOX production in the presence of the plasma was low (similar to < 1EINO(X)); however, it increased with decreasing velocity and pressure, and increasing temperature.