Under which one of the following sets of conditions will a supersonic compressor have the highest efficiency?
(a) Rotor inlet velocity is supersonic and exit velocity subsonic; stator inlet velocity is subsonic and exit velocity is subsonic
(b) Rotor inlet velocity is supersonic and exit velocity subsonic: statot inlet velocity is supersonic and exit velocity is subsonic
(c)Rotor inlet velocity is supersonic and exit velocity supersonic; stator inlet is supersonic and exit velocity is subsonic.
(d) Rotor inlet velocity is supersonic and exit velocity supersonic: stator inlet velocity is subsonic and exit velocity is subsonic.