Numerical Investigation on Effects of Profiled Endwall Over Purge Flow in Linear Turbine Cascade

Abstract

This paper describes the combined effects of purge flow and non-axisymmetric endwall profiling on the aerothermal performance of a linear turbine cascade. Purge slot with 45° ejection angle and three different endwall profiles, with varying hump to dip height, are analyzed. Performance of profiled endwall is compared with the non-profiled case. Reynolds-averaged Navier–Stokes (RANS) equation with SST turbulence model is used for numerical simulation. The analyzed results explore the demerits of current endwall profiles and how the transverse movement of weaker boundary layer fluid from the hub-pressure side corner enhanced. Compared to base case, endwall profiling enhanced the overturning and secondary flow kinetic energy at cascade exit. Apart from this, the profiled cases are providing very effective endwall protection compared to non-profiled purge case. © 2020, Springer Nature Singapore Pte Ltd.