The secondary passages on the gas turbine engine fuel nozzles shown in the illustration are designed to open at approximately what pressure? See illustration GT-0005

Correct Answer: Option B — 330 PSIG

Dual-orifice fuel nozzles utilize a primary and secondary flow path to ensure stable combustion across the entire operating range. The secondary passage opens at a specific pressure, approximately 330 PSIG, to provide the additional fuel flow required for higher power demands while maintaining proper atomization and spray patterns.