Compressor diffuser and diffuser pipes therefor

A diffuser for a compressor of a gas turbine engine, the diffuser comprising:

• a plurality of diffuser pipes circumferentially distributed about an axis of the compressor, each of the plurality of diffuser pipes extending from an inlet to an outlet, a bend section between the inlet and the outlet, a low pressure side and an opposite high pressure side, the low pressure side and the high pressure side extending on opposite sides of a longitudinal plane coinciding with a center line of a given one of the plurality of the diffuser pipes and extending along the center line;
• and
• a recirculation conduit defining a recirculation path from a first flow region to a second flow region in one or more of the plurality of the diffuser pipes, the first flow region having a greater static pressure than that of the second flow region, the recirculation conduit having a conduit inlet and a conduit outlet, the conduit inlet and the conduit outlet located within the low pressure side of a same one of the plurality of the diffuser pipes, the conduit inlet downstream of the conduit outlet relative to a main flow of air through the diffuser.

A diffuser for a compressor of a gas turbine engine, the diffuser comprising:

• a plurality of diffuser pipes circumferentially distributed about an axis of the compressor, each of the plurality of diffuser pipes extending from an inlet to an outlet, a bend section between the inlet and the outlet, a low pressure side and an opposite high pressure side, the low pressure side and the high pressure side extending on opposite sides of a longitudinal plane coinciding with a center line of a given one of the plurality of the diffuser pipes and extending along the center line;
• and
• a recirculation conduit defining a recirculation path from a first flow region to a second flow region in one or more of the plurality of the diffuser pipes, the first flow region having a greater static pressure than that of the second flow region, the recirculation conduit having a conduit inlet and a conduit outlet, at least the conduit outlet located within the low pressure side of one of the plurality of the diffuser pipes, wherein the conduit inlet has a longitudinal dimension L1 taken in a direction along a length of the one of the plurality of the diffuser pipes from which the conduit inlet receives part of a main flow of air through the diffuser, and a transverse dimension L2 taken transversely to L1, wherein 1<L2/L1<3.