ICSV26

The circular mesh antenna is designed as a lightweight and flexible structure in the orbit and use mainly metal meshes as a reflecting surface. This paper analyzes frequencies and modal shapes of the circular mesh antenna by using the finite element method, and the nonlinear resonant responses of the circular mesh antenna are studied based on a circular cylindrical shell equivalent model clamped along a generatrix and with membranes at both ends. Firstly, we establish the finite element model of the circular mesh antenna considering the influences of meshes on the vibration characteristics of the circular mesh antenna. It is found that there exist the 1:3 internal resonance under a certain mesh stiffness between the first-order and the fourth-order vibrations of the circular mesh antenna, and we give the comparison of the first six orders vibration modal shapes under the different mesh stiffness cases to study the influences of mesh stiffness on the vibration modal shapes of the circular mesh antenna. Then, we obtain the four-dimensional nonlinear averaged equation based on the two degrees of freedom non-autonomous nonlinear equations of the circular mesh antenna equivalent model considering this case of 1:3 internal resonance. At last, we compute the curves of equilibria in order to study the nonlinear resonant responses of the equivalent circular mesh antenna model. The amplitude-frequency response curves and the parametric excitation amplitude curves of the system on the state-parameter space are obtained, meanwhile, jump points and Antronov-Hopf points are detected and located on these resonance response curves. Furthermore, the effects of temperature excitation on amplitude-frequency response curves of the equivalent circular mesh antenna model are investigated.