全流向球形十八孔压力探针的发展及应用

The strong three-dimensional and unsteady characteristics of the unstable flow in the turbomachinery pose challenges for experimental measurement. The multi-hole pressure probe measurement technology is the only method for simultaneous measurement of three-dimensional velocity vector, static pressure and total pressure in experimental measurement technology. In this paper, a novel 18-hole probe layout based on the regular icosahedron, which optimizes the utilization of measurement holes is designed. A set of well-performing dimensionless coefficients were designed according to the layout characteristics, and a corresponding data processing method was developed based on the pressure sorting partitioning method. The probe was experimentally calibrated. Considering the sources of error, a comprehensive analysis of the uncertainty during the calibration process has been conducted, taking into account the influence of instrument environment, interpolation methods, and overlapping areas of the grid. The results indicate that, with a 95% confidence level, the prediction errors for the deflection angle and pitch angle are within 0.45° and 0.18°, respectively, and the error in the magnitude of velocity is within 0.32%. The probe was used to measure the rotating stall flow field of a low-speed counter-rotating compressor, and the results indicate that the probe effectively identifies the recirculation characteristics upstream of the rotor in the complex three-dimensional stall flow field. The presented stall structure is similar to the results of numerical simulations and wall hot-wire experiments, validating the reliability of the eighteen-hole pressure probe in the measurement of three-dimensional unsteady flow fields.