Inter-row traveling shock (IRTS) has been proved to be of significant impacts on many unsteady flow phenomena in transonic turbines, especially on IRTS-shock wave interaction and IRTS-wake interaction. Therefore, it is necessary to reveal the flow mechanisms of the above phenomena to prevent inappropriate aerodynamic excitation or undesirable flow loss in turbines. In this paper, the equivalent cascade model, the unsteady wake vortex surrogate model considering viscous dissipation, and the IRTS disturbance function are proposed to analyze flow mechanisms. The Unsteady Reynolds-Averaged Navier–Stokes model is used for simulations. For IRTS-shock interaction, nine different vane/blade axial spacings are considered from which three groups are found to be of different shock system structures and corresponding evolution patterns, causing different aerodynamic excitation modes and levels' variations of 6.58% on vane and 4.26% on blade. For IRTS-wake interaction, the wake deflection—characterized by a circumferential deflection rate of at least 38%—stems from the stretching of the distance between the wake vortex pair. This stretching is caused by the injection of kinetic energy from the IRTS into the pressure-side vortex blob. Meanwhile, it is also pointed out that the foundation of IRTS-wake interaction lies in the influence of IRTS on velocity derivative fields, thereby changing vortex structure and local flow loss by approximately 20%. IRTS-wake interaction exerts a stronger influence on suction-side vortex blobs compared to those on the pressure side, with IRTS intensity and width as the most important factors.
Shen et al. (2026) studied this question.