两级可调增压系统具有高度结构紧凑性，系统间存在气流相互干涉产生的强耦合作用，从而导致涡轮性能发生变化。从可调两级增压系统级间流场测量手段展开论述，详细探究了涡轮入口流场测量方法，设计了一种基于X型恒温热线风速仪的全自动步进测量方法，测量了35°旋流发生器在径流涡轮入口处产生的旋流。测量结果表明，随着质量流量的改变，旋流角的大小与旋流发生器叶片偏转角度保持一致，稳定在35°~36°之间，旋流的轴向速度与切向速度变化趋势相同，由管壁向管道中心逐渐增大且在圆心处增加至最大。该研究验证了X型二维热线测量涡轮入口旋流的可行性和精确性，为两级可调增压系统管内流动测量方法及管路结构优化设计提供了参考。

The two-stage adjustable turbocharging system has an extremely compact structure, the interference of air flow between the systems leads to a strong coupling effect, and hence the turbine performance changes. The interstage flow field measurement of two-stage adjustable turbocharging system was first discussed, the measurement method of turbine inlet flow field was explored in detail, and a fully automatic step measurement method based on X-type constant temperature hot-wire anemometer was designed. The swirl generated by the 35° swirl generator at the inlet of radial turbine was measured. The measurement results show that the magnitude of swirl angle keeps between 35° and 36° and is consistent with the deflection angle of swirl generator blade with the change of mass flow rate. In addition, the variation trends of swirl axial and tangential velocity are the same, which increases gradually from the pipe wall to the pipe center and reaches the maximum at the center of circle. Therefore, the feasibility and accuracy of X-type two-dimensional hot-wire is proved by measuring the swirl flow at the inlet of turbine, which provides the reference for the flow measurement method and pipeline structure optimization design of two-stage adjustable turbocharging system.