Uncertainty and global sensitivity analysis of flutter characteristics for air rudder

For the structural parameter uncertainty can cause flutter characteristics fluctuation, uncertainty and global sensitivity analysis is conducted for flutter characteristics of air rudder. The computational efficiency decreases greatly with the dimensions of uncertainty variables. To solve this problem, the sparse grid technology is used to uncertainty and global sensitivity analysis, which can be efficiently carried out uncertainty analysis and global sensitivity analysis for high-dimensional problems, and a numerical example is conducted to validate the method. The elastic constraints and material properties are considered to be uncertainties, and the uncertainty and global sensitivity analysis are conducted by calling flutter analysis model. The results show that the uncertainty of the structural parameters has greater impact on flutter modal damping and frequency characteristics nearby critical flutter speed. In addition, the impact of the elastic constraint which effect branch modal characteristics of flutter has biggest influence on flutter.