A method for producing a rotating turbine blade and tuning the natural frequencies of the blade is disclosed that changes the second effective beam length of the blade thereby changing the separation between the first natural frequency and the second natural frequency of the blade.

A bladed rotor system for a turbomachine includes a circumferential row of blades mounted on a rotor disc, and includes a plurality of under-platform dampers. Each damper is located between adjacent blade platforms. The plurality of dampers includes a first set of dampers and a second set of dampers. The dampers of the first set are distinguished from the dampers of the second set by a cross-sectional material distribution in the damper that is unique to the respective set. Dampers of the first set and the second set are positioned alternately in a periodic fashion in a circumferential direction, to provide a frequency mistuning to stabilize flutter of the blades.

A bladed rotor system for a turbomachine includes a circumferential row of blades mounted on a rotor disc, and includes a plurality of under-platform dampers. Each damper is located between adjacent blade platforms. The plurality of dampers includes a first set of dampers and a second set of dampers. The dampers of the first set are distinguished from the dampers of the second set by a cross-sectional material distribution in the damper that is unique to the respective set. Dampers of the first set and the second set are positioned alternately in a periodic fashion in a circumferential direction, to provide a frequency mistuning to stabilize flutter of the blades.

Damping systems are provided for a rotor blade platform. The damping system may include a blade platform defining a damper pocket and a CMC wedge damper positioned within the damper pocket. The CMC wedge damper has at least one damper angled surface parallel to a longitudinal axis. The damper pocket comprises a pocket angled surface positioned about the at least one damper angled surface.

A fluid-flow machine includes at least one rotor having a rotary element with a plurality of rotor blades arranged on the rotary element, and a circumferential casing having a central axis and surrounding the rotor. The circumferential casing or a part connected thereto has an annular space surface on the inside, which delimits a flow duct of the fluid-flow machine radially outwards. The annular space surface has a structuring at least in one area adjoining a rotor on the circumferential side. At least one structuring of the annular space surface has, relative to the central axis of the circumferential casing, a circumferentially asymmetrical design.

A fluid-flow machine includes at least one rotor having a rotary element with a plurality of rotor blades arranged on the rotary element, and a circumferential casing having a central axis and surrounding the rotor. The circumferential casing or a part connected thereto has an annular space surface on the inside, which delimits a flow duct of the fluid-flow machine radially outwards. The annular space surface has a structuring at least in one area adjoining a rotor on the circumferential side. At least one structuring of the annular space surface has, relative to the central axis of the circumferential casing, a circumferentially asymmetrical design.

A gas turbine stator for aircraft engines has a blade array with a plurality of blades constituted by a series of first blades and a series of second blades with different geometries; the array is formed by a plurality of sectors, each having an inner portion, an outer portion, at least one first blade and a least one second blade, and each defined by a body made in one piece; a single first blade is alternated with a single second blade for the entire circumference of the stator.

A gas turbine stator for aircraft engines has a blade array with a plurality of blades constituted by a series of first blades and a series of second blades with different geometries; the array is formed by a plurality of sectors, each having an inner portion, an outer portion, at least one first blade and a least one second blade, and each defined by a body made in one piece; a single first blade is alternated with a single second blade for the entire circumference of the stator.

In accordance with one embodiment of the present disclosure, a system includes a first housing, a second housing, a seal, and a spring system. The first housing includes a first volume of fluid. The first housing is capable of connecting to a first element and to a second element, and is also capable of reducing an amount of movement transferred from the first element to the second element. The second housing is connected to the first housing. The second housing includes a second volume of fluid and a volume of gas. The first volume of fluid is in fluid communication with the second volume of fluid. The seal is capable of separating the second volume of fluid from the volume of gas. The spring system is capable of applying pressure to the first volume of fluid and the second volume of fluid.

In accordance with one embodiment of the present disclosure, a system includes a first housing, a second housing, a seal, and a spring system. The first housing includes a first volume of fluid. The first housing is capable of connecting to a first element and to a second element, and is also capable of reducing an amount of movement transferred from the first element to the second element. The second housing is connected to the first housing. The second housing includes a second volume of fluid and a volume of gas. The first volume of fluid is in fluid communication with the second volume of fluid. The seal is capable of separating the second volume of fluid from the volume of gas. The spring system is capable of applying pressure to the first volume of fluid and the second volume of fluid.