Solution to Boundary-value Problems in Fabrication of High-precision Reflector Panels

The fabrication of high-precision panels for the compact antenna test range (CATR) with a sandwich construction of two aluminum skin-plates and one aluminum middle plate, which are bonded to two aluminum honeycomb core-layers poses a lot of tricky problems. Of them, the force analysis of individual skin-layers and the springback calculation of sandwich are of utmost importance. Under reasonable assumptions, by using Fourier expansion of stress function and power series expansion of deflection function, two boundary-value problems of skin-layer and sandwich, i.e. force analysis and springback calculation, are solved. An analytical solution of stress function in series form and an approximate solution of deflection function are obtained. Compared with finite element method (FEM), the generalized double Fourier series method used in individual skin force analysis is superior in accuracy. Compared with experimental results, the weighted residual method used in springback calculation of sandwich-structured panel is acceptable from view of precision. Based on calculation results, processing parameters to panel fabrication are determined more efficient and accurate.