The Analysis Of SRAM Stealth Performance Computation And Its 2-D Structural Optimization

The structural radar absorption materials (SRAM) of composites, with the dual functions of high mechanic properties and reducing radar cross-section (RCS), are the key means of stealth technique implementation for modern aircrafts. By use of electromagnetic finite element method and optimization design technique, this thesis conducts the research work of SRAM stealth performances computation and theoretical optimization analysis of electromagnetic parameters, and also some typical cases are studied.On the base of analyzing SRAM classifications and structural models, possible stealth design approaches, feasible numerical calculations and detailed optimization design techniques are explored in the thesis, meanwhile, the algorithmic procedures and programs of 2-D target RCS are designed and worked out by virtue of the finite element method (FEM) for the boundary problem of second-order linear partial differential equations combined with absorbing boundary conditions (ABC). The numerical results worked in the thesis are so agreed with the solutions of moment method (MM), which indirectly shows the program correctness and applicability. Underlying on these fundamental researches, the optimization design concepts of SRAM are investigated and the parametric optimization algorithmic codes under sequential quadratic programming (SQP) are designed. Some optimal results valuable for engineering design are achieved to the specific SRAM at designated electromagnetic frequencies. With regards of SRAM structural models design, the thesis preliminarily analyzes 2-D layered and rippled SRAM structures possessed of certain referential value for engineering.