Computational analysis of pitch-width effects on the secondary flows of turbine blades

摘要

The results of this study provide useful information for evaluation of the secondary flow effects due to the pitch-width ratio influence for the future new turbine blade designs. A three-dimensional computational code using a novel time-marching method was employed for solving time-averaged flows within a turbine blade row. A concept of incorporating dissipation terms into the time derivative terms was proposed to allow the code to have the capability of handling both incompressible and compressible flows. The code was validated by comparing the computational results with experiments in a turbine stator blade passage. The influences of secondary flow in a turbine blade row due to different pitch-width ratios were investigated. Detailed secondary flows as well as loss profiles in different root pitch-width ratio are presented and discussed. This study enhances the knowledge of secondary flows features and benefits the future turbine design.