United Technologies Corporation

Hamilton Sundstrand Corporation

Robert Hans Schlinker

John C Simonich

Satish Narayanan

Wesley K Lord

Anthony C Jones

Gregory A Kohlenberg

James C Napier

Ramons Andris Reba

Marios C Soteriou

Scott A Liljenberg

Thierry Pascal Maeder

David R Polak

Daniel W Shannon

Ray-Sing Lin

Chad M Henze

Ramons A Reba

Joseph M Verdon

Edward J Kerschen

Thierry Maeder

Kenneth A Kousen

John Simonich

Satish Naravanan

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.

Differential blade design for propeller noise reduction

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.

System for reducing compressor noise

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.

Asymmetric serrated nozzle for exhaust noise reduction

A system for reducing jet noise emission from an internally mixed gas turbine engine exhaust, comprising a fan/core flow mixer having a plurality of mixer lobes and a common flow nozzle having an equal number of tabs located along a circumferential edge of an aft end of the nozzle. There is a predetermined clocking relationship between the plurality of mixer lobes and the plurality of nozzle tabs that results in reduced exhaust noise emission, most evident in the lower frequency range. A method for reducing jet noise emission from an internally mixed gas turbine engine exhaust comprises selectively aligning a circumferential distribution of a mixed flow vorticity field produced by a fan/core mixer with a circumferentially distributed exhaust flow vorticity field produced by a modified common flow nozzle at an exit plane of the engine exhaust.

Jet exhaust noise reduction system and method

Acoustic noise resulting from the interaction of a periodic pressure and velocity fluctuation induced by a periodically passing blade wake interacting with a downstream airfoil (10)is attenuated by locating an antisymmetric pressure wave generator (30) adjacent the leading edge (18) of the vane (10).

Airfoil noise control

An arrangement for cancelling unwanted noise generated by sequential blade rows (16, 18) in a gas turbine engine (10) includes a plurality of acoustic sources (52) disposed on the blades (36-42) of the downstream row (18).

Anti-sound arrangement for multi-stage blade cascade

Growing community of inventors

Canton, CT, United States of America

Robert Hans Schlinker