Abstract: Flow separation in diffuser with large divergence angle seriously affects the performance and flow distortion of diffuset. In this study the vortex control technique is used for suppressing the diffuser flow separation. The designed vortex trap on the diffuser wall makes the velocity distribution changed and increases the momentum of boundary layer near the diffuser wall. The effect of configuration of vortex trap on the suppression of separation is described in this paper. Based on the measuring parameters of diffuser flow the mechanism of the vortex control technique is also discussed.

Key words: diffuser, inlet, vortex control, separation flow