Thrust load compensating system for a compliant foil hydrodynamic fluid film thrust bearing

A thrust load compensating system for a turbomachine, comprising:

• a power head having a compressor and turbine on a common shaft rotatably supported by a compliant foil hydrodynamic fluid film journal bearing and a bilateral compliant foil hydrodynamic fluid film thrust bearing;
• a permanent magnet generator with a permanent magnet generator shaft having one end coupled to the compressor end of said power head common shaft and a free end rotatably supported by a compliant foil hydrodynamic fluid film journal bearing, said permanent magnet generator also including a stator having internal cooling fins with said stator disposed around said permanent magnet generator shaft;
• a fixed end cap mounted over the free end of said permanent magnet generator shaft;
• and
• a separate tubular conduit extending directly from said compressor to the interior of said fixed end cap to provide compressor bleed air having a gauge pressure that varies approximately with the square of turbomachine speed, directly to the free end of said permanent magnet generator shaft to thrust bias said permanent magnet generator shaft towards said power head.

A thrust load compensating system for a turbomachine, comprising:

• a power head having a compressor and turbine on a common shaft rotatably supported by a compliant foil hydrodynamic fluid film journal bearing and a bilateral compliant foil hydrodynamic fluid film thrust bearing;
• a permanent magnet generator with a permanent magnet shaft having one end coupled to the compressor end of said power head common shaft and a free end rotatably supported by a compliant foil hydrodynamic fluid film journal bearing, said permanent magnet generator also including a stator having internal cooling fins with said stator disposed around said permanent magnet generator shaft;
• a fixed end cap mounted over the free end of said permanent magnet generator shaft;
• and
• a separate tubular conduit extending directly from said compressor to the interior of said fixed end cap to provide compressor bleed air having a gauge pressure that varies approximately with the square of turbomachine speed, directly to the free end of said permanent magnet generator shaft to thrust bias said permanent magnet generator shaft towards said power head;
• the free end of said permanent magnet generator shaft serves as a movable thrust piston, said fixed end cap mounted over the free end of said permanent magnet generator machine shaft serves as a non-rotating thrust cylinder cap, and the compliant foil hydrodynamic fluid film journal bearing rotatably supporting the free end of said permanent magnet generator shaft serves as a non-rotating contacting piston ring seal to together form a pressure chamber with the movable thrust piston.

A thrust load compensating system for a turbomachine, comprising:

• a power head having a compressor and a turbine on a common shaft rotatably supported by a compliant foil hydrodynamic fluid film journal bearing and a bilateral compliant foil hydrodynamic fluid film thrust bearing, said compressor including a compressor wheel and plenum;
• a rotary machine with a shaft having one end coupled to the compressor end of said power head common shaft and a free end rotatably supported by a compliant foil hydrodynamic fluid film journal bearing;
• a fixed end cap mounted over the free end of said rotary machine shaft;
• and
• a separate tubular conduit extending directly from said compressor to the interior of said fixed end cap to provide compressor bleed air from said compressor plenum, having a gauge pressure that varies approximately with the square of turbomachine speed, directly to the free end of said rotary machine shaft,
• said fixed end cap mounted over the free end of said rotary machine shaft serves as the end of a non-rotating thrust cylinder, the free end of said rotary machine shaft serves as a movable thrust piston, the compliant foil hydrodynamic fluid film journal bearing rotatably supporting the free end of said rotary machine shaft function as the walls of the pressure cylinder surrounding said movable thrust piston, said fixed end cap mounted over the free end of said rotary machine shaft and the compliant foil hydrodynamic fluid film journal bearing rotatably supporting the free end of said rotary machine shaft together form a pressure chamber for the free end of said rotary machine shaft movable thrust piston, and the compliant foil hydrodynamic fluid film journal bearing rotatably supporting the free end of said rotary machine shaft end of said rotary machine shaft serves as a non-contacting piston ring seal.