US Patent 10378551 Counter-rotating compressor

A compressor is described which includes a non-axial first rotor, and a second rotor disposed immediately downstream from the first rotor and being co-axial therewith about a longitudinal axis of rotation. The second rotor rotates in a direction opposite the non-axial first rotor to discharge fluid flow into an uninterrupted passage between an outlet of the second rotor and one of a downstream combustor or a further compression stage. The uninterrupted passage is free of a diffusing passage. A gas turbine engine including such a compressor and a method of compressing fluid flow is also described.