The design methods of typical supersonic aircraft intakes and shock wave compression technology have been applied to ram-rotor,an attractive compression system.A ram-rotor is of a typical structure including the compression ramp,the throat and the subsonic diffuser;a scrampressor is similar to ram-rotor,the only difference is that scrampressor has no subsonic diffuser.The work was the continuation of the preparatory work.In order to further study the effect of throat contraction ratio and strake stagger angle on the flow field and performance of a scrampressor,the flow field of a scrampressor with a three-dimensional flow path was numerically simulated with different throat contraction ratios and strake stagger angles.Simulated results indicated that the optional aerodynamic performance of a scrampressor could be achieved with an adiabatic efficiency of 0.8413atotal pressure recovery coefficient of 0.8446,a total pressure ratio of 7.14 and a static pressure ratio of 5.17for a throat contraction ratio of 0.6 and a strake stagger angle of 12°.It was therefore concluded that an appropriate decrease in throat contraction ratio and an increase in strake stagger angle could help the comprehensive improvement of a scrampressor in performance. The design methods of typical supersonic aircraft intakes and shock wave compression technology have been applied to ram-rotor, an attractive compression system. A ram-rotor is of a typical structure including the compression ramp, the throat and the subsonic diffuser; a scrampressor is similar to ram-rotor, the only difference is that scrampressor has no subsonic diffuser. The work was the continuation of the preparatory work. In order to further study the effect of throat contraction ratio and strake stagger angle on the flow field and performance of a scrampressor, the flow field of a scrampressor with three-dimensional flow path was numerically simulated with different throat contraction ratios and strake stagger angles. Simulated results indicated that the optional aerodynamic performance of a scrampressor could be achieved with an adiabatic efficiency of 0.8413 atotal pressure recovery coefficient of 0.8446, a total pressure ratio of 7.14 and a static pressure ratio of 5.17 for a throat co ntraction ratio of 0.6 and a strake stagger angle of 12 ° .It was therefore concluded that an appropriate decrease in throat contraction ratio and an increase in strake stagger angle could help the comprehensive improvement of a scrampressor in performance.