Abstract: An apparatus and method for suppressing dynamic instability in a bleed duct of a gas turbine engine includes a fan bypass duct configured to permit a flow of air through the gas turbine engine. The fan bypass duct defines a fan duct surface, and the bleed duct has an inlet in fluid communication with the fan bypass duct and a flow control valve having an opened position and a closed position. A flow diverter is positioned on the fan duct surface proximate the inlet of the bleed duct and diverts the flow of air from the inlet when the flow control valve is closed, while permitting a portion of the flow of air to enter the inlet when the flow control valve is opened.

Abstract: A bleed duct is configured for bleeding fan air from the fan bypass duct in a turbofan aircraft engine. The bleed duct includes a tubular conduit having an inlet and outlet at opposite ends. The conduit is configured in flow area for recovering pressure from speeding fan air bled therethrough. A shroud extends forwardly from the duct inlet for suppressing dynamic pressure oscillations inside the conduit without degrading the pressure recovery.

Abstract: An apparatus and method for suppressing dynamic instability in a bleed duct of a gas turbine engine includes a fan bypass duct configured to permit a flow of air through the gas turbine engine. The fan bypass duct defines a fan duct surface, and the bleed duct has an inlet in fluid communication with the fan bypass duct and a flow control valve having an opened position and a closed position. A flow diverter is positioned on the fan duct surface proximate the inlet of the bleed duct and diverts the flow of air from the inlet when the flow control valve is closed, while permitting a portion of the flow of air to enter the inlet when the flow control valve is opened.

Abstract: A method for operating a pulse detonation system. The method includes providing a pulse detonation chamber including a plurality of detonation tubes extending therein, and detonating a mixture of fuel and air within each detonation tube such that at least a first tube is detonated at a different time than at least a second detonation tube.

Abstract: A method for operating a pulse detonation system. The method includes providing a pulse detonation chamber including a plurality of detonation tubes extending therein, and detonating a mixture of fuel and air within each detonation tube such that at least a first tube is detonated at a different time than at least a second detonation tube.

Abstract: A method for operating a pulse detonation system. The method includes providing a pulse detonation chamber including a plurality of detonation tubes extending therein, and detonating a mixture of fuel and air within each detonation tube such that at least a first tube is detonated at a different time than at least a second detonation tube.

Abstract: A method for operating a pulse detonation system. The method includes providing a pulse detonation chamber including a plurality of detonation tubes extending therein, and detonating a mixture of fuel and air within each detonation tube such that at least a first tube is detonated at a different time than at least a second detonation tube.

Abstract: A fan casing for a gas turbine engine is provided which combines the functions of blade containment and noise suppression. The fan casing has an annular metallic inner shell with a plurality of holes are formed therethrough. An acoustic absorber, such as a cellular resonator, is disposed around the inner shell.

Abstract: A fan casing for a gas turbine engine is provided which combines the functions of blade containment and noise suppression. The fan casing has an annular metallic inner shell with a plurality of holes are formed therethrough. An acoustic absorber, such as a cellular resonator, is disposed around the inner shell.