Glass viscous damper
Rotor blades, vibrational dampening elements, and methods are provided. A rotor blade includes a platform, a shank extending radially inward from the platform, and an airfoil extending radially outward from the platform. One or more fluid chambers are defined within the rotor blade. Glass is disposed within each fluid chamber of the one or more fluid chambers. A mass is disposed within each fluid chamber of the one or more fluid chambers. The mass is movable within the glass relative to the airfoil.
1. A rotor blade for a turbomachine, the rotor blade comprising:
a platform;
a shank extending radially inward from the platform; and
an airfoil extending radially outward from the platform, wherein one or more fluid chambers are defined within the rotor blade;
glass disposed within each fluid chamber of the one or more fluid chambers; and
a mass disposed within each fluid chamber of the one or more fluid chambers, the mass movable within the glass relative to the airfoil, wherein the glass includes a viscosity of between 10 −4 pascal seconds (Pa-s) and 10 −2 Pa-s at a temperature of between 600° C. and 900° C.
2. The rotor blade as in claim 1 , wherein the airfoil includes a leading edge, a trailing edge, a pressure side wall extending between the leading edge and the trailing edge, and a suction side wall extending between the leading edge and the trailing edge, wherein the one or more fluid chambers is defined collectively by the leading edge, the trailing edge, the pressure side wall, and the suction side wall.
3. The rotor blade as in claim 2 , wherein the mass includes a first portion extending between the leading edge and the trailing edge and a second portion extending generally perpendicularly to the first portion.
4. The rotor blade as in claim 3 , wherein a first pair of guides extend from the pressure side wall and a second pair of guides extend from the suction side wall, and wherein the second portion is disposed between the first pair of guides and the second pair of guides.
5. The rotor blade as in claim 3 , wherein the airfoil extends from a root coupled to the platform to a tip, and wherein the mass is attached at the root of the airfoil.
6. The rotor blade as in claim 2 , wherein the airfoil defines a radial channel, and wherein separating walls extend within the radial channel and at least partially define the one or more fluid chambers.
7. The rotor blade as in claim 1 , wherein the glass has a viscosity that changes with a temperature of the glass in accordance with one of FIG. 11 or FIG. 12 .
8. A vibrational dampening element attached to a turbine component and configured to adjust an amplitude of oscillations of the turbine component, the vibrational dampening element comprising:
a mass;
a casing encapsulating the mass; and
a fluidic chamber defined between the mass and the casing and filled with glass, wherein the glass includes a viscosity of between 10 −4 pascal seconds (Pa-s) and 10 −2 Pa-s at a temperature of between 600° C. and 900° C.
9. The vibrational dampening element as in claim 8 , wherein the glass has a softening temperature of between 100° C. to 900° C.
10. The vibrational dampening element as in claim 8 , wherein the glass is a chalcogenide glass.
11. The vibrational dampening element as in claim 8 , wherein the glass has a viscosity that changes with a temperature of the glass in accordance with one of FIG. 11 or FIG. 12 .
12. A method of adjusting an amplitude of oscillations of a turbine component disposed in a turbine section of a turbomachine, the method comprising:
providing the turbine component having a fluid chamber and a mass disposed within the fluid chamber; and
disposing glass within the fluid chamber;
wherein operation of the turbine results in a decrease of a viscosity of the glass to produce a molten-state glass, the mass being translated through the molten-state glass to adjust the amplitude of oscillations of the turbomachine component.
13. The method as in claim 12 , wherein the turbomachine component is a rotor blade.
14. The method as in claim 12 , wherein the turbomachine component is a vibrational dampening element.
15. The method as in claim 12 , wherein the glass has a softening temperature of between 100° C. to 900° C.
16. The method as in claim 12 , wherein the glass includes a viscosity of between 10 −4 pascal seconds (Pa-s) and 10 −2 Pa-s at a temperature of between 600° C. and 900° C.
17. The method as in claim 12 , wherein the glass possesses shear thinning characteristics such that as an acceleration of the mass increases a resistive shear force of the molten-state glass decreases.
18. The method as in claim 12 , wherein the glass has a viscosity that changes with a temperature of the glass in accordance with one of FIG. 11 or FIG. 12 .