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用三维激光多普勒测速技术测量了扩压叶栅出口近端壁区域的流动结构和紊流特性。实验结果表明，气流流出扩压叶栅出口后，吸力面和压力面的通道涡将在较长的距离内保持其形态和强度，但是尾迹的形成及尾迹在压力的作用下向吸力面方向的偏斜成为了这一阶段的主要流动现象。通道涡、尾迹和尾迹的运动对亲流量的分布规律具有决定性的影响。随着流体向下游运动，尾迹区内雷诺正应力分量的衰减和扩散均比雷诺切应力快。而通道涡区域紊流量的值则变化不大。
The flow structure and turbulent characteristics in the proximal wall of diffuser cascade were measured by three-dimensional laser Doppler velocimetry. The experimental results show that the passage vortex at the suction side and the pressure side will maintain its shape and strength over a longer distance after the air stream exits the outlet of the diffuser cascade. However, the formation and wake of the wake are under pressure to the suction side Deflection has become the main phenomenon of this phase. The movement of channel vortices, wakes and wakes has a decisive influence on the distribution of in-flux. As the fluid moves downstream, the true Reynolds stress component in the wake region decays and diffuses faster than the Reynolds stress. The value of turbulence in the channel vortex area changed little.