Uncertainty analysis of effects of end wall fillet radius error on high-load stator cascade performance

To provide a strong reference for the high-precision design and manufacture of the compressor stators，a high-load compressor stator cascade was used as the research object，and the non-intrusive polynomial chaos method based on Gaussian random input was used to quantitatively evaluate the uncertainty effect of the end wall fillet radius manufacturing error on the aerodynamic performance under the minimum loss and near stall conditions.Results showed that the uncertainty of the fillet radius error had little effect on the average level of aerodynamic performance，which was mainly reflected by the standard deviation of aerodynamic performance parameters.The robustness of aerodynamic performance can be nearly doubled by increasing the manufacturing accuracy of the fillet radius.When the manufacturing accuracy was constant，the robustness of total pressure losses under near stall conditions should be focused on to conduct the robustness design of the blade.According to the correlation analysis between the end wall fillet radius in the tolerance zone and the aerodynamic performance under near stall conditions，the fillet radius had a linear relationship with the aerodynamic performance，and it was required to avoid the use of blades with a rounding radius smaller than the nominal so as to obtain better aerodynamic performance.Through the uncertainty analysis of the near stall flow field，the separated flow was more sensitive to the rounding radius manufacturing error，which was the main factor causing the uncertainty of the aerodynamic performance.