Turbine blade squealer tip

Abstract

A turbine blade having a squealer tip coupled to a radially outer end of the turbine blade that is usable in a gas turbine engine is disclosed. The squealer tip may require less cooling air and may therefore be more efficient than conventional configurations. The squealer tip may be formed from one or more materials such as oxide dispersion strengthened alloys and FeCrAl alloys. The squealer tip may be formed from a plurality of segmented tips extending radially outward and spaced apart from each other. For example, the squealer tip may be formed from two rails extending radially outward and spaced apart from each other. The two rails may be formed from outer and inner rails that each form a continuous ring. The squealer tip may be attached to the tip with a transient liquid phase bond or an additive manufacturing process, such as, a selective laser melting process.

Description

FIELD OF THE INVENTION[0001]This invention is directed generally to turbine blades, and more particularly to tip sealing systems for turbine blades.BACKGROUND[0002]Typically, gas turbine engines include a compressor for compressing air, a combustor for mixing the compressed air with fuel and igniting the mixture, and a turbine blade assembly for producing power. Combustors often operate at high temperatures that may exceed 2,500 degrees Fahrenheit. Typical turbine combustor configurations expose turbine blade assemblies to these high temperatures. As a result, turbine blades must be made of materials capable of withstanding such high temperatures. In addition, turbine blades often contain cooling systems for prolonging the life of the blades and reducing the likelihood of failure as a result of excessive temperatures.[0003]Typically, turbine blades are formed from a root portion at one end and an elongated portion forming an airfoil that extends outwardly from a platform coupled to ...

AI Technical Summary

Benefits of technology

[0005]A turbine blade having a squealer tip coupled to a radially outer end of the turbine blade that is usable in a gas turbine engine is disclosed. The squealer tip may be configured such that the squealer tip requires less cooling fluids than conventional squealer tips, therefore increasing the efficiency of the turbine engine in which the squealer tip is used. In at least one embodiment, the squealer tip may use about 1.5 percent less cooling fluids than conventional turbine blades. In addition, the squealer tip may also be configured to be used in turbine engines that are designed to operate at higher operating temperatures than conventional turbine engines. The squealer tip may be formed from a material that is different than the material forming the turbine blade.

[0007]The squealer tip may be formed from a plurality of segmented tips extending radially outward and spaced apart from each other to relieve thermal stress at the tip. To relieve thermal stress in the squealer tip, the squealer tip may be formed from two rails extending radially outward and spaced apart from each other. The two rails may be formed from outer and inner rails that each form a continuous ring.

[0009]An advantage of this invention is that the squealer tip may enable turbine blade tips to be exposed to higher temperatures without an increased risk of failure.

[0010]Another advantage of this invention is that the squealer tip may be made with materials that would reduce cooling requirements at the tip and improve blade clearance while increasing the operating efficiency of the turbine engine by about ½ percent.

[0011]Yet another advantage of this invention is that the squealer tip may be formed from segmented tips to alleviate thermal stress in the squealer tip.

Problems solved by technology

In addition, turbine blades often contain cooling systems for prolonging the life of the blades and reducing the likelihood of failure as a result of excessive temperatures.

These higher temperatures are creating increased thermal stress levels on the turbine airfoils.

However, centrifugal forces and air flow at boundary layers often prevent some areas of the turbine blade from being adequately cooled, which results in the formation of localized hot spots.

Localized hot spots, depending on their location, can reduce the useful life of a turbine blade and can damage a turbine blade to an extent necessitating replacement of the blade.

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