Abstract: A gas turbine engine includes a combustor having a combustor air inlet, an axial-centrifugal compressor, a shroud, a secondary flow duct, and a valve. The shroud surrounds at least a portion of the axial-centrifugal compressor and has a surge bleed plenum defined therein that is in fluid communication with, and receives compressed air from, the axial compressor outlet. The secondary airflow duct has a duct inlet that is in fluid communication with the surge bleed plenum, and a duct outlet that is in fluid communication with the combustor air inlet. The valve is mounted on the secondary airflow duct and is movable between a closed position, in which the secondary airflow duct does not provide fluid communication between the surge bleed plenum and the combustor air inlet, and an open position, in which the secondary airflow duct provides fluid communication between the surge bleed plenum and the combustor air inlet.

Abstract: A gas turbine engine includes a combustor having a combustor air inlet, an axial-centrifugal compressor, a shroud, a secondary flow duct, and a valve. The shroud surrounds at least a portion of the axial-centrifugal compressor and has a surge bleed plenum defined therein that is in fluid communication with, and receives compressed air from, the axial compressor outlet. The secondary airflow duct has a duct inlet that is in fluid communication with the surge bleed plenum, and a duct outlet that is in fluid communication with the combustor air inlet. The valve is mounted on the secondary airflow duct and is movable between a closed position, in which the secondary airflow duct does not provide fluid communication between the surge bleed plenum and the combustor air inlet, and an open position, in which the secondary airflow duct provides fluid communication between the surge bleed plenum and the combustor air inlet.

Abstract: Gas turbine engine (GTE) compressor sections and compressor intake ducts are provided having Soft Foreign Object debris (SFOD) endwall treatments, which reduce peak damage to GTE components in the event of SFOD ingestion. In embodiments, the GTE compressor section includes a compressor rotor and a compressor intake duct. The compressor intake duct includes an intake flow passage, which extends through compressor intake duct to the compressor rotor. A first duct endwall extends around a centerline of the flow passage to bound a peripheral portion of the intake flow passage. An SFOD endwall treatment includes topological features formed in or otherwise provided on the first duct endwall. The topological features of the SFOD endwall treatment are configured such that SFOD impacting the topological features is directed in a radially inward direction toward the flow passage centerline prior discharge of the SFOD from the intake flow passage and into the compressor rotor.

Abstract: Gas turbine engine (GTE) compressor sections and compressor intake ducts are provided having Soft Foreign Object debris (SFOD) endwall treatments, which reduce peak damage to GTE components in the event of SFOD ingestion. In embodiments, the GTE compressor section includes a compressor rotor and a compressor intake duct. The compressor intake duct includes an intake flow passage, which extends through compressor intake duct to the compressor rotor. A first duct endwall extends around a centerline of the flow passage to bound a peripheral portion of the intake flow passage. An SFOD endwall treatment includes topological features formed in or otherwise provided on the first duct endwall. The topological features of the SFOD endwall treatment are configured such that SFOD impacting the topological features is directed in a radially inward direction toward the flow passage centerline prior discharge of the SFOD from the intake flow passage and into the compressor rotor.