Patent ID: 7581920

Claim:
An air circulation method in a turbomachine compressor, said compressor comprising: several compression stages each composed of a bladed rotor with blades and a bladed stator with vanes, an outer casing and an inner casing, delimiting a flowpath in which the blades of the rotor and the vanes of the stator are located, a main airflow passing through said flowpath, an outer part of the flowpath called the outer flowpath, corresponding to functional clearances between the outer casing and the blades of the rotor, and an inner part of the flowpath called the inner flowpath, corresponding to functional clearances between the inner casing and the vanes of the stator, the method comprising the following steps, for at least one compression stage comprising a stator: providing labyrinths on said inner casing between said two adjacent blades, said labyrinths facing a vane between said two adjacent blades, wherein said labyrinths do not touch said vane such that said functional clearances defining said inner flowpath are present between said labyrinths and said vane, sucking in air from the main airflow, through said functional clearances between said labyrinths and said vane and through a radially inner orifice of said vane faced by said labyrinths, directing the sucked in air through said vane, bleeding said air from said vane through a radially outer opening of said vane and through an orifice of said outer casing, and collecting said air from said vane into a manifold outside the compression stage.