Abstract: In accordance with certain embodiments, a wind turbine blade includes an outer skin and an internal support structure. The skin has a closed airfoil shape and includes an outer surface, an inner surface, and opposite sides along a length of the blade. The internal support structure is disposed within the closed airfoil shape. The internal support structure includes at least one shear load bearing member disposed across the opposite sides and oriented lengthwise along the length of the blade. The internal support structure further includes a plurality of bending load bearing members disposed along the inner surface in a lengthwise direction along the length of the blade. The internal support structure is configured to position a shear center and a center of aerodynamic pressure loading of the blade at different locations relative to one another.

Abstract: A steam turbine blade includes a shank portion and an airfoil portion. The airfoil portion is formed with at least one pocket filled with a polymer filler material chosen as a function of natural frequency impact on the turbine blade or as a function of the damping characteristics of the filler materials. A steam turbine rotor wheel includes a plurality of blades secured about a circumferential periphery of the wheel, each blade having one or more pockets in the airfoil portion, the plurality of blades divided into two groups of blades. The pockets of one group of blades are filled with one or more polymer filler materials, and the pockets of the other group of blades filled with one or more polymer filler materials, wherein the polymer filler materials in the one group of blades creates different natural frequencies or damping characteristics in the blades of the one group than the polymer filler materials in the blades of the other group.

Abstract: A method of manufacturing a blade for assembly on a steam turbine rotor wheel includes forming an airfoil portion with plural pockets and filling the pockets with more than one filler material chosen as a function of required temperature capability.

Abstract: A system for controlling blade tip clearance in a turbine. The system includes a stator including a shroud having a plurality of shroud segments and a rotor including a blade rotatable within the shroud. An actuator assembly is positioned radially around the shroud and includes a plurality of actuators. A sensor senses a turbine parameter and generates a sensor signal representative of the turbine parameter. A modeling module generates a tip clearance prediction in response to turbine cycle parameters. A controller receives the sensor signal and the tip clearance prediction and generates at least one command signal. The actuators include at least one actuator receiving the command signal and adjusts a position of at least one of the shroud segments in response to the command signal.