Compressor boundary layer bleeding system
AssigneeA/S Kongsberg Vapenfabrikk
InventorIvar H. Skoe
Life of this patent
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Abstract
Acoustically sized bleed passages are provided in the shroud wall of a rotary compressor to admit expansion waves to the suction-sides of successive passing blades to control the boundary layer. The expansion waves are generated by reflecting compression waves formed in the passages by the pressure sides of passing blades. The passages are oriented to receive high pressure bleed gas at maximum gas particle velocity, and the passages are configured to diffuse the gas to increase static bleed pressure.
Claims18
Improved method for controlling the fluid boundary layer in a compressor having a plurality of blades rotating in a housing, the method including the step of continuously extracting fluid from the region of the housing wall through at least one bleed passage formed in the housing wall to a fluid collector, the bleed passage having an inlet and an outlet, the improvement in the extracting step comprising the step of periodically lowering the static pressure at the bleed passage inlet to coincide with the arrival of the suction sides of the compressor blades, for increasing the amount of fluid extracted from the suction sides for a given collector static pressure.
Improved apparatus for controlling the fluid boundary layer in a compressor having a plurality of blades rotating in a housing, the apparatus having at least one bleed passage through the housing wall connected to a fluid collector for continuously extracting fluid from the region of the housing wall, the bleed passage having an inlet and an outlet, the improvement comprising:
- means for periodically lowering the static pressure at the bleed passage inlet to coincide with the arrival of the suction sides of successive blades for increasing the amount of fluid extracted from the suction sides for a given collector static pressure, wherein said pressure lowering means includes means for periodically generating expansion waves in the bleed passage, said expansion waves travelling in the direction opposite that of the flow of fluid being extracted and means for timing the arrival in succession of each of said expansion waves at the bleed passage inlet to occur immediately after a blade has passed the passage inlet.
Dependencies are inferred from the claim text.