Global sensitivity and design space of drag characteristics of parametric airship hull

To effectively reduce the dimension of the design parameters of airship hulls, improve the design efficiency, and provide reference and guidance for the design of airship hulls in the initial stage, an evaluation system was constructed for the airship hull shape parameters associated with drag coefficient sensitivity, combined with parametric section (PARSEC) method, computational fluid dynamics (CFD) method, and Sobol global sensitivity analysis method based on variance. First, the outline of airship hull was described by PARSEC method which has clear physical significance. Then, the drag coefficient of airship hull samples produced by Latin hypercube sampling (LHS) was obtained by 2D axisymmetric CFD method. The accuracy of CFD method was verified by the experimental data of six typical streamlined bodies of revolution. Under the condition that the Reynolds number was consistent, the average relative error between the calculated and experimental drag coefficient was 1.5%. Finally, the sensitivity of the hull shape parameters was ranked by the Sobol global sensitivity analysis method. Research results show that the three parameters which were the most sensitive to the hull drag coefficient were the head radius rh, the maximum radius rd, and the maximum radius position xd. On the basis of this study, the design space of the airship hull shape was formed, and the design space has positive significance for improving the efficiency of designing process and reducing the aerodynamic drag of airships. Copyright ©2021 Journal of Harbin Institute of Technology.All rights reserved.