A "caret" inlet was designed for Mach number 2.0 according to theory of waverider.The experimental investigation on flow characteristics of a large S-shaped diffuser with such an inlet has been carried out.The flow characteristics of the inlet and the S-shaped diffuser have been analysed by means of flow visulization on the walls

measurements of total pressure recovery distribution and velocity vector plots in the sections concerned.The performance of this large S-shaped diffuser was compared with that of the same diffuser but with conventional inlet.It is shown that

under takeoff condition and at the same Ma2 of the diffusers

the total pressure recovery of the former is a little higher but the circumferential total pressure distortion index △ σo and DC60 of the former are larger than that of the latter.