Secondary flow control using endwall jet fence in a high-speed compressor cascade

This paper proposes a secondary flow control concept using Endwall jet fence (EJF). A parametric investigation concerning the variations of the jet location along the axial and pitch-wise direction as well as the skew angle is conducted numerically to validate the potential of EJF in a high-speed compressor cascade with an inlet Mach number of 0.67. And then the interaction mechanisms between the EJF and the endwall secondary flow are discussed in detail. The results show that the EJF could reduce the corner separation and losses significantly by inputting transverse momentum component, inducing a concentrated jet vortex to block the pitch-wise migration of the passage vortex as well as enhancing the energy exchange between the endwall boundary layer and the mainstream. The jet location and the skew angle are important for the influence of EJF on the cascade performance. In this work, a maximum total pressure loss reduction of 11.6 % is obtained by the EJF located at 30 % of the axial chord and 10 % of the pitch with a skew angle of β = 40°, whereas the jet-to-inflow mass flow ratio is only about 0.4 %, validating the high efficiency of this flow control concept. For the off-design points, the EJF also shows appreciable potential on the endwall secondary flow control and loss reduction.