Customer bleed air pressure loss reduction

A gas turbine engine comprising:

• a compressor delivering air into a combustion section having a combustor, and said combustion section and said compressor being housed in a housing, an air supply system communicating through said housing to deliver air from a location between an upstream end of said compressor, and an upstream end of said combustor;
• said air supply system having a duct with a duct inlet end and extending to an outlet end, said duct being provided with a central insert at an upstream end, said central insert providing a venturi effect by reducing the cross-sectional flow between the insert and an inner wall of the duct at the upstream end, and said insert and duct providing increased cross-sectional flow areas at downstream locations, said insert ending within said duct upstream of said outlet end;
• said air supply system includes a plurality of said ducts, each of said ducts being provided with an insert, and said ducts inlet ends at locations spaced by at least 90° about a cross-sectional center axis of the gas turbine engine;
• a diffuser positioned downstream of said compressor, an opening in said housing supplying air to said duct inlet ends, and said diffuser having an outer shroud and an inner shroud with intermediate vanes, and said outer shroud ending at a location upstream of a downstream end of said inner shroud at locations circumferentially aligned with said duct inlet end, said outer shroud only ends at the upstream location at circumferential locations associated with said duct inlet end, but extends further downstream at other locations;
• and
• a flow path through said opening, and into said inlet end of said duct has at least a portion formed with a part-circular radius.

A gas turbine engine comprising:

• a compressor delivering air into a combustion section having a combustor, and said combustion section and said compressor being housed in a housing, an air supply system communicating through said housing to deliver air from a location between an upstream end of said compressor, and an upstream end of said combustor;
• said air supply system having a duct with an inlet end;
• a diffuser positioned downstream of said compressor, and said diffuser having an outer shroud and an inner shroud with intermediate vanes, and said outer shroud ending at a location upstream of the downstream end of said inner shroud at locations circumferentially aligned with said inlet end;
• and
• said outer shroud only ends at the upstream location at circumferential locations associated with said inlet ends, but extends further downstream at other locations.