Effect of elastic deformation on the trajectory of aerial separation

Uncertain serious threats to fight vehicle exist during the process of releasing objects or launching weapons. Reynolds-averaged Navier-Stokes equations are solved through CFD technique in this paper. Based on the frame of unstructured mesh, techniques of dynamic chimera mesh and inverse-distance-weighted morphing mesh are adopted to treat the multi-body separation and flexible structure deformation caused by aeroelasticity respectively. Moreover, the six-degree freedom dynamic equations are solved with static aeroelastic equations by means of the modal approach. Effect of elastic deformation on the trajectory of aerial separation is intensively researched. Numerical results of store-separation case and static aeroelastic case calculated using the in-house code both agree well with the experimental data respectively, which validates of the numerical method. An air-to-air missile model of X-X configuration is constructed to research the effect of elastic deformation on the trajectory of the releasing body. Comparison results of flexible and rigid models show that the longitudinal and course trajectory of centroid is affected by the elastic deformation, and the oscillatory cycle of the orientation angle increases. Furthermore, the trajectories of rigid models with various centroid locations are computed, illustrating that the elastic deformation could move the aerodynamic center forward and weaken the margin of the stability. This study demonstrates that more attention should be paid to the effect of elastic deformation during the fining design of the trajectory of aerial separation.