Investigation of Nonlinear Aerothermoelastic Characteristics of the Deployable Control Fin Using Tightly Coupled Fluid-Thermal-Structural Interaction Analysis

In this study, aerothermoelastic analysis of a control fin using tightly coupled fluid-thermal-structural interaction method is presented. The fin with freeplay nonlinearity is subjected to Mach 6 hypersonic flow with non-zero angle of attack. A finite volume method-based fluid flow solver is tightly coupled to a Finite element method based structural dynamics solver in the time domain using mapping-based coupling technique. Diffusion function-based smoothing method is used for the CFD grid deformation. The fin is connected to a finite stiffness actuator at the root. The effect of freeplay at the deployable joint is investigated and flow field, structural, and thermal quantities are reported for various freeplay conditions. Obtained results indicate increased instability in the fin oscillations due to an increase in the freeplay at the deployable joint.