Abstract: A propeller is provided including a hub and a first blade group and a second blade group. The first blade group includes at least one first propeller blade and the second blade group includes at least one second propeller blade. The at least one first propeller blade and the at least one second propeller blade are mounted to and equidistantly spaced about the hub. The at least one first propeller blade of the first blade group has at least one geometric characteristic different from the at least one propeller blade of the second blade group. The different blade groups will generate different noise signatures over a wider range of frequencies allowing for the design of low noise propeller systems.

Abstract: A propeller is provided including a hub and a first blade group and a second blade group. The first blade group includes at least one first propeller blade and the second blade group includes at least one second propeller blade. The at least one first propeller blade and the at least one second propeller blade are mounted to and equidistantly spaced about the hub. The at least one first propeller blade of the first blade group has at least one geometric characteristic different from the at least one propeller blade of the second blade group. The different blade groups will generate different noise signatures over a wider range of frequencies allowing for the design of low noise propeller systems.

Abstract: A system for reducing compressor noise includes a rotor having a plurality of blades. The blades have a nominal geometry characterized by a blade parameter. At least some of the blades are mistuned, such that they differ from the nominal geometry by greater than a manufacturing tolerance in the blade parameter. The blades produce shock waves at a blade passing frequency, and the mistuned blades shift acoustic energy away from the blade passing frequency to multiple lower amplitude tones at other frequencies. The system is configurable to be deployed with an inlet silencer that preferentially absorbs acoustic energy at some of the shifted frequencies.

Abstract: A system for reducing compressor noise includes a rotor having a plurality of blades. The blades have a nominal geometry characterized by a blade parameter. At least some of the blades are mistuned, such that they differ from the nominal geometry by greater than a manufacturing tolerance in the blade parameter. The blades produce shock waves at a blade passing frequency, and the mistuned blades shift acoustic energy away from the blade passing frequency to multiple lower amplitude tones at other frequencies. The system is configurable to be deployed with an inlet silencer that preferentially absorbs acoustic energy at some of the shifted frequencies.

Abstract: An exhaust nozzle for use in a gas turbine engine comprises a flow body for receiving exhaust gas from the turbine engine and includes a leading edge and a trailing edge. The leading edge connects with the gas turbine engine such that the flow body surrounds a centerline of the engine. The trailing edge comprises a serrated portion and a non-serrated portion. The serrated portion is formed from a plurality of tabs for mixing exhaust gas exiting the flow body with gases passing by an exterior of the flow body. The non-serrated portion is positioned along a lower portion of the trailing edge with respect to the engine centerline.

Abstract: A fuel delivery system includes a fuel stabilization unit that receives vibratory energy for mixing fuel within fuel passages to improve the removal of dissolved oxygen from an oxygen containing fuel. A vibration generator transmits vibratory energy into the fuel stabilization unit to induce mixing of fuel. Vibratory energy is directed into the fuel to create enhanced mixing by inducing large-scale secondary flow motions that circulates fuel from a center flow area toward an oxygen permeable surface to improve overall fuel deoxygenation as more of the fuel is placed in adjacent contact with the oxygen permeable membranes.

Abstract: An exhaust nozzle for use in a gas turbine engine comprises a flow body for receiving exhaust gas from the turbine engine and includes a leading edge and a trailing edge. The leading edge connects with the gas turbine engine such that the flow body surrounds a centerline of the engine. The trailing edge comprises a serrated portion and a non-serrated portion. The serrated portion is formed from a plurality of tabs for mixing exhaust gas exiting the flow body with gases passing by an exterior of the flow body. The non-serrated portion is positioned along a lower portion of the trailing edge with respect to the engine centerline.