Abstract: An arrangement for intentionally mistuning a cavity formed adjacent an impeller in a turbomachine, the arrangement including at least two bladed elements defined within a perimeter of a casing wall adjacent the impeller, wherein the bladed elements are configured to mistune cavity acoustic modes to minimize acoustic pulsations in the cavity.

Abstract: An arrangement for intentionally mistuning a cavity formed adjacent an impeller in a turbomachine, the arrangement including at least two bladed elements defined within a perimeter of a casing wall adjacent the impeller, wherein the bladed elements are configured to mistune cavity acoustic modes to minimize acoustic pulsations in the cavity.

Abstract: A turbomachine includes a plurality of rotating blades adjacent to a plurality of stationary vanes attached to a stationary casing. Stationary vanes are spaced apart circumferentially with equal spacing around an inner perimeter of the casing. Optionally, stationary vanes are offset radially and/or circumferentially. Stationary vanes may alternate with leading and/or trailing edges at different distances from the rotating blades. In one embodiment, stationary vanes have tapered leading and/or trailing edge angles to homogenize flow and reduce stator wake excitation, flow excitation, and acoustic excitation due to interaction with spinning modes of acoustic pressure pulsations at rotating blade passing frequency.

Abstract: A bearing apparatus for reducing vibrations in a compressor shaft (17) carrying a rotating compressor (10) is provided. The bearing apparatus comprises a first bearing (14) for supporting the shaft (17) and a second bearing (13) spaced outboard from the first bearing (14) for producing a moment on the shaft and additional damping counter to the direction of vibrations.

Abstract: A bearing apparatus for reducing vibrations in a compressor shaft (17) carrying a rotating compressor (10) is provided. The bearing apparatus comprises a first bearing (14) for supporting the shaft (17) and a second bearing (13) spaced outboard from the first bearing (14) for producing a moment on the shaft and additional damping counter to the direction of vibrations.

Abstract: A compressor blade vibration reduction mechanism for a high-speed radial impeller for minimizing fatigue failures from various excitation sources. The vibration reduction mechanism includes a plurality of loose-fitting lashing pins coupling each impeller blade to an adjacent impeller blade. Each lashing pin extends through a first aperture in a blade located adjacent to the blade tip and through a second aperture of an adjacent blade. The second aperture of each blade is located a greater distance from the leading edge of the blade than the first aperture. The second aperture is located in an area of the blade having lower vibration during operation than the blade location where the first aperture is located.

Abstract: A method for preventing one-cell rotating stall initiated by a bladed disc having a plurality of blades including the steps of identifying a one-cell stall condition and modifying one or more blades to force the bladed disc into at least a two-cell stall pattern. This can be accomplished by modifying the spacing between the blades to force the bladed disc into at least a two-cell stall pattern. Alternatively, at least one of the blades can be geometrically modified so as to force the bladed disc into at least a two-cell stall pattern.