## 5 Conclusions  
In this study, a comprehensive analysis of the aerodynamic characteristics and the combined dynamic derivative of a typical cylindrical projectile are presented by using the FVM combined with the SST k-\(\omega\) turbulence model. On this basis, the improved efficient Sobol global sensitivity analysis method based on the ARBF surrogate model and LH sampling is used to analyze the sensitivity of design parameters on the cylindrical projectile's aerodynamic characteristics. The conclusion is as follows:  
1. For the cylindrical projectile model, the lift-to-drag ratio increases with the increase in the angle of attack from 0\({}^{\circ}\) to 30\({}^{\circ}\), and then the lift-to-drag ratio tends to decrease when the angle of attack exceeds 60\({}^{\circ}\); the absolute value of the pitching moment coefficient firstly increases with the increase in the angle of attack, and the static stability of the cylindrical projectile model becomes better after the angle of attack is 60\({}^{\circ}\); with the increase in the angle of attack, the dynamic derivative of the cylindrical projectile model fluctuates in a small range, and the maximum value occurs when the angle of attack is 30\({}^{\circ}\), which means that the dynamic stability of the model is the worst at this time.  
Figure 8: Histogram of total sensitivity analysis results of the pitch moment coefficient with the different angles of attack.  
Figure 7: Histogram of sensitivity analysis results at the angle of attack at 10\({}^{\circ}\). **(a)** The first-order sensitivity; **(b)** The total sensitivity.  
2. The centroid position has the greatest effect on the lift coefficient and drag coefficient, while the incoming velocity has the greatest effect on the pitch moment coefficient and combined dynamic derivatives, when the angle of attack is \(10^{\circ}\); at different angles of attack, the effect of the four design parameters on the aerodynamic characteristics varies. In order to ensure the dynamic performance of the different angle of attack maneuvering, the influence of these four parameters should be fully and comprehensively considered in practical design. This study provides a typical case for the analysis and design of related engineering systems' aerodynamic characteristics, providing important theoretical and engineering value.  
Conceptualization, S.J., L.T. and H.W.; methodology, S.J., L.T. and W.R.; software, S.J., L.T. and X.W.; validation, L.T.; formal analysis, L.T.; investigation, S.J.; resources, S.J., L.T. and H.W.; data curation, L.T.; writing--original draft preparation, S.J. and L.T.; writing--review and editing, S.J., and L.T.; supervision, W.R. and H.W.; project administration, S.J. and H.W.; funding acquisition, S.J. All authors have read and agreed to the published version of the manuscript. This research received no external funding.  
Not applicable. Data sharing not applicable, as this article describes a method of dynamics modeling and analysis, and the data supporting this study have been made available within the article.  
The authors declared that they have no conflicts of interest regarding this work. We do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted. The work described has not been submitted elsewhere for publication, in whole or in part, and all the authors listed have approved the manuscript that is enclosed.