Reduction of turbomachinery noise

A turbomachine blade comprising:

• at least one internal mass flow injection passage extending from a corresponding open injection passage inlet at blade hub to a corresponding open injection passage outlet at a port in the blade at a blade chord line more than about 75% blade chord along at least a portion of blade span, and comprising an internal injection passage volume substantially sufficient to accommodate fluid mass flow from the injection passage inlet to the injection passage outlet;
• a plurality of separated injection slots in the blade along at least a portion of the blade span corresponding to the open passage outlet of the at least one injection passage, the injection slots together comprising an outlet port area substantially sufficient to inject from the internal injection passage into a trailing edge wake produced as the blade rotates a mass flow of fluid that reduces momentum deficit characteristic of the wake;
• at least one internal mass flow suction passage extending from a corresponding suction passage end region at the point along blade span to the corresponding open suction passage outlet at blade tip, and comprising an internal suction passage volume substantially sufficient to accommodate fluid mass flow from the suction passage end region to the suction passage outlet;
• and
• a plurality of separated suction slots in a side of the blade characterized as a relatively low-pressure blade side, along at least a portion of the blade span corresponding to the suction passage end region of the at least one suction passage, the suction slots together comprising a suction area substantially sufficient to suction into the internal suction passage from a boundary layer produced as the blade rotates a mass flow of fluid that reduces momentum deficit characteristic of the wake.

A turbomachine comprising:

• a rotor having a plurality of rotor blades each connected at a rotor blade hub to a rotor disk for rotation about a radial axis of the disk;
• a stationary blade upstream of the rotor, the stationary blade having at least one internal passage extending between a corresponding open passage inlet at one end of the stationary blade to a corresponding open passage outlet at a stationary blade chord line more than about 75% of stationary blade chord along at least a portion of stationary blade span, and comprising an internal passage volume substantially sufficient to accommodate fluid mass flow from the passage inlet to passage outlet, a plurality of separated slots being located in the stationary blade along at least a portion of the stationary blade span corresponding to the open passage outlet of the at least one internal passage, the slots together comprising an outlet port having an area substantially sufficient to inject into a trailing edge stationary blade wake produced as fluid flows around the stationary blade a mass flow that reduces momentum deficit characteristic of the stationary blade wake;
• and
• a coupling path from the open passage inlet of the stationary blade to a compressor for providing a source of high pressure to the at least one internal passage of the stationary blade.

A turbomachine comprising:

• a rotor having a plurality of rotor blades each connected at a blade hub to a rotor disk for rotation about a radial axis of the disk;
• a stationary blade upstream of the rotor, the stationary blade having at least one internal passage extending from a corresponding passage end region at a point along stationary blade span to an open passage outlet at one end of the stationary blade, and comprising an internal passage volume substantially sufficient to accommodate fluid mass flow from the passage end region to the passage outlet, a plurality of separated slots being located in a side of the stationary blade along at least a portion of the stationary blade span corresponding to the passage end region of the at least one internal passage, the slots together comprising a suction port having an area substantially sufficient to suction into the internal passage from a boundary layer produced as fluid flows around the stationary blade a mass flow of fluid that reduces momentum deficit characteristic of a stationary blade wake produced as fluid flows around the stationary blade;
• and
• a coupling path from the open passage outlet of the stationary blade to a pump in a casing of the rotor for providing a source of low pressure to the at least one internal passage of the stationary blade.

A turbomachine comprising:

• a rotatable shaft;
• a support strut engaged with the shaft for supporting the shaft as it rotates;
• and
• a plurality of blades, each blade being connected at a blade hub to the shaft and having at least one internal blade passage extending from a corresponding open passage inlet, for coupling at the blade hub to a source of high pressure, to a corresponding open passage outlet at a blade chord line more than about 75% of blade chord along at least a portion of blade span, and comprising an internal passage volume substantially sufficient to accommodate fluid mass flow from the passage inlet to the passage outlet, a plurality of separated slots being located in the blade along at least a portion of the blade span corresponding to the open passage outlet of the at least one internal blade passage, the slots together comprising an outlet port having an area substantially sufficient to inject into a trailing edge wake produced as the blade rotates a mass flow of fluid from the high pressure source that reduces momentum deficit characteristic of the blade wake.

A turbomachine comprising:

• a rotatable shaft;
• a support strut engaged with the shaft at an end of the shaft for supporting the shaft as it rotates;
• and
• a plurality of blades, each blade being connected at a blade hub to the shaft and having at least one internal blade passage extending from a corresponding passage end region at a point along blade span to a corresponding open passage outlet at blade hub for coupling to a source of low pressure, and comprising an internal passage volume substantially sufficient to accommodate fluid mass flow from the passage end region to the passage outlet, a plurality of separated slots being located in a side of the blade characterized as a relatively low-pressure blade side, along at least a portion of the blade span corresponding to the passage end region of the at least one internal passage, the slots together comprising a suction port having an area substantially sufficient to suction to the low pressure source through the internal blade passage from a boundary layer produced as the blade rotates a mass flow of fluid that reduces momentum deficit characteristic of a wake produced as the blade rotates.