Effects of rotational motion on dynamic aeroelasticity of flexible spinning missile with large slenderness ratio

Abstract

Abstract The structural rigidity of a spinning missile with large slenderness ratio is usually small, and the structural deformation and rate should not be ignored. Furthermore, rotational motion makes the aeroelasticity more complicated. Therefore, unsteady Euler equations and generalized dynamic aeroelastic equations are coupled simultaneously to simulate the dynamic aeroelastic response of a spinning missile with large slenderness ratio using rigid-motion mesh and radial-basis-function (RBF) morphing mesh techniques. The unsteady Euler equations are solved by computational fluid dynamics (CFD) technique by the in-house code. The Coriolis term and centrifugal loading term due to rotational motion are both considered in the generalized dynamic aeroelastic equations. The rigid-motion mesh and RBF morphing mesh techniques are both based on unstructured mesh, and the rigid-motion mesh is adopted to treat the rigid motion due to rotational motion, while the RBF morphing mesh is employed for flexible structural deformation caused by aeroelasticity. Numerical results of aeroelastic case are well agreed with the experimental results, which validates the numerical method. A missile model with X-X configuration is constructed to investigate the effects of rotational motion on dynamic aeroelasticity. The dynamic aeroelastic responses of the missile with and without rotational motion are simulated, respectively. Comparison results show that the lateral modes and longitudinal modes are coupled together because of rotational motion. In addition, the structural natural frequencies are changed due to rotational motion. In the end, detailed numerical analysis of the generalized dynamic aeroelastic equations used in this paper indicates the mechanism by which the rotational motion leads to the coupling of lateral modes and longitudinal modes and changes the structural natural frequencies.