Study on Aerodynamic Effect of Leading-Edge Radius Error and Tolerance Design Considering Compressor Airfoil Size Characteristic

The aerodynamic layout of compressor blades has difference with the position varying, so the blade size characteristics are different. If the size characteristics are not considered, it is worth discussing whether it is reasonable to use the same range of tolerance constraints for the same type of machining errors. To study the above issue, a subsonic airfoil is taken as the research object, and its size is magnified by 1 time to obtain 2 sets of cascades with 1 time difference in the chord length, and the leading-edge radius errors are added to explore the difference in the effect on the deviation degree and scatter of the aerodynamic performance. The results show that when the geometric size increases, the influence degree of the leading-edge radius error on the performance deviation decreases. When the relative value of the leading-edge radius error is equal to that of the chord length, the performance deviation degree of 2 sets of cascades almost coincides. Due to the influence of error uncertainty, the performance scatter of 2 sets of cascades is almost doubled, and the large-size one is smaller, indicating that the rationality of using the same range of tolerance constraints for different sizes of airfoils is insufficient, and it should be considered comprehensively in combination with its size characteristics. In addition, from the perspective of qualified aerodynamic performance, the acceptance range of performance is set, and the error bounds are back-calculated by the uncertainty quantification method. It is found that the error range of the large-size one is wider. The greater the scatter of aerodynamic performance, the more stringent tolerance constraints are needed. The research work aims to further establish the relationship between blade machining and performance research, and to provide a new idea for the design of machining tolerance range in engineering.