[1][2] The exit mean radius is greater than at the inlet, like a centrifugal design, but the flow tends to exit in an axial rather than radial direction.
This eliminates the need for a relatively large diameter exit diffuser associated with centrifugal compressors.
Diagonal compressors were widely experimented during and just after World War II, but did not see much service use.
A diagonal-flow compressor is featured since 2001 in the Pratt & Whitney Canada PW600 series turbofan engines used in the Phenom 100, Eclipse 500, Cessna Citation Mustang and other very light jet aircraft.
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