ACOUSTICALLY STIFFENED GAS-TURBINE FUEL NOZZLE

摘要

Under certain conditions, the fuel delivery system can contribute to the formation of strong dynamic pressures in the combustor of a turbine engine. Embodiments of the invention provide a system for dynamically stiffening the fuel supply passage to suppress combustion dynamics. To that end, a Helmholtz resonator (48) can be placed along and in branched relation to the fuel supply passage (10). The resonator (48) can produce the effect of adding a pressure release opening at a selected location in the fuel line (10), causing a shift in the fuel line pressure wave pattern (40) that blocks fuel flow fluctuations at the outlet (16) of the fuel passage (10) at the frequency of the oscillation. The pressure wave (40) shift results in a shifting of the volume velocity wave pattern (42). Ideally, the resonator (48) can be positioned along the flow path (10) such that the volume velocity of the fuel (22) at the fuel passage exit (16) is minimized.