Turbine wheel for hot gas turbine engine

Patent · Tue Apr 08 00:00:00 EST 1986

OSTI ID:5855679

Scully, A J

This patent describes a turbine wheel in a gas turbine engine. The improvement consists of an axial flow turbine designed to receive pressurized gases at temperatures above 2000/sup 0/ F. The turbine consists of a rotor and annular flow passage structure. The rotor includes a central hub, individual separately-formed blades extending radially outwardly from the hub periphery within the flow passage, and an endless annular reinforcement band affixed to outer tip areas of the blades. The blades are formed of ceramic refractory material having high compressive strength but relatively low tensile strength. The endless annular band is formed of a high tensile strength material. The band convertes centrifugal force on the rotor into compressive loadings on the blades. The band material has a higher coefficient of thermal expansion than the blade-material. The passage structure has an annular recess therein sized to surround outer surface areas of the band so that the band offers minimal resistance to flow of high temperature gases through the blade area. The outer surface of the band is spaced radially inwardly from the recess surface to define an annular band coolant space. Means for circulating relatively cool gas through the coolant space maintains the band at a significantly lower temperature blades. Thermal expansion of the band in the radial direction is reduced to a level approximating that of the blades. Each blade is connected to the central hub by means of a radial socket formed in the hub periphery, and a blade root section extending into the associated socket. Each blade root section has a nonlocking snug fit in the associated socket whereby centrifugal force puts the blade material under compression rather than tension.

• Assignee: Secretary of the Army, Washington, DC
• Patent Number(s): US 4580943
• OSTI ID: 5855679
• Resource Relation: Patent File Date: Filed date 29 Dec 1980
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
GAS TURBINE ENGINES
GAS TURBINES
ANNULAR SPACE
CERAMICS
COMPRESSION
COMPRESSION STRENGTH
COOLANTS
PRESSURIZING
REFRACTORIES
REINFORCED MATERIALS
ROTORS
TEMPERATURE CONTROL
TENSILE PROPERTIES
THERMAL EXPANSION
TURBINE BLADES
CONFIGURATION
CONTROL
ENGINES
EXPANSION
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
MACHINERY
MATERIALS
MECHANICAL PROPERTIES
SPACE
TURBINES
TURBOMACHINERY
330103* - Internal Combustion Engines- Turbine