US Patent 10066640 Optimized circumferential groove casing treatment for axial compressors

A compressor is provided. The compressor includes a rotating member configured to rotate about an axis and a static member radially adjacent the rotating member with a clearance between the static member and the rotating member. A first groove is disposed circumferentially about the static member and radially adjacent the rotating member. A second groove is disposed circumferentially about the static member and a first axial distance aft of the first groove. A third groove is disposed circumferentially about the static member and a second distance aft of the second groove, wherein the first distance is different from the second distances.