## 3 Results and Discussion
### Effect of Wake on the Integrated LPT-GV  
Based on the above analysis conclusions about the transport mechanism of sweeping wakes with different \(d/s\) values and their influence on the internal flow of the AITD, the effect of the remaining wake on the flow characteristics of the integrated LPT-GV, especially the boundary layer separation, viscosity loss and vortex structure in blade passages, is described in detail below. Figure 11: Distribution of the pitchwise mass-averaged total pressure coefficient and its contour in Section B6. Figure 10: Time-averaged streamwise vorticity contour in different sections of the AITD. Figure 12 shows the distribution of the time-averaged static pressure coefficient on the integrated LPT-GV in the AITD under different sweeping wake conditions. A pressure plateau appeared on the Cps curve of the suction surface in all cases, and the area of the plateau decreased with increasing \(d/s\). This result meant that the residual wakes still could not completely suppress the flow separation on the suction surface, but the stronger wake in the case of a larger \(d/s\) had a better suppressing effect on the separation bubble. The reduction in separation bubbles increased the effective flow area of the LPT-GV passage to a certain extent, which improved the static pressure coefficient of the LPT-GV. As the mass flow rate was constant, the wake blockage effect increased the velocity in the LPT-GV passages, resulting in a decrease in the static pressure coefficient. In the case of \(d/s=0.10\), the static pressure coefficients at the three sections were almost the same as those when \(d/s=0.078\) because the flow passage blockage caused by the enhanced wake in this case could offset its effect of increasing the flow area by suppressing separation. When \(d/s=0.122\), the static pressure coefficient was significantly lower than that of the other two cases, as shown in Figure 12, which indicated that the reduction in the flow area caused by the blockage effect of the strong wake was significantly greater than the increase in the flow area caused by its inhibition of the flow separation bubble in this case. Moreover, in this case, the decrease in the static pressure coefficient on the suction surface was larger than that on the pressure surface, which indicated that the pressure gradient from the pressure surface to the suction surface increased, especially in the section of a 15% span. Figure 13 shows the limiting streamline and static pressure coefficient contour on the suction surface of the integrated LPT-GV when \(d/s=0.078\), \(0.10\) and \(0.122\). A passage vortex, marked by 'PV@C' in Figure 13, appeared on the upper part of the LPT-GV suction surface in all cases, and this vortex disappeared on the suction surface as it broke away from the wall downstream (discussed in detail below). Comparing the cases with different \(d/s\) values, the area of these passage vortices decreased with increasing \(d/s\). The area of PV@C was significantly smaller when \(d/s=0.122\) compared to the other two cases, as shown in the figure where \(t=0.2\)T. This difference arose because when \(d/s\) was large due to the reduced radial pressure gradient from the hub to the shroud, the accumulation of low-energy fluid near the shroud and the horseshoe vortex at the leading edge of the LPT-GV were weakened, and the passage vortex developed by the horseshoe vortices entraining low-energy fluids was bound to be reduced. At the midspan of the LPT-GV, the residual wake could well inhibit the boundary layer separation on the suction surface in all cases, and the stronger wake could inhibit the flow separation earlier and more persistently in the cases with larger \(d/s\). For example, the midspan flow separation was completely suppressed from \(t=0.15\)T to \(t=0.75\)T when \(d/s=0.122\), while the separation bubble was not completely inhibited until \(t=0.30\)T and recovered at \(t=0.54\)T when \(d/s=0.078\).