Aerodynamic And Stealth Design

With the higher requirement of the survival ability and combat efficiency of the aircraft, stealth performance becomes a very important guideline in the aircraft design. Because stealth performance depends on the aerodynamic configuration and the material, designers should synthetically consider the aerodynamic and stealth design in early conceptual stage of aircraft by using radar absorbing materials and shaping technology. Based on the multi-objective optimization theory, the optimization design system on the configuration, radar absorbing painting and spray positions is built up by Pareto optimization method.The work is performed as follows:1. The RCS program on a perfectly conducting wedge is written based on Incremental Length Diffraction Coeffcients (ILDC). The RCS of metallic aircraft can be accurately computed by using of Physical Optics and ILDC.2. The RCS program on an impedance object is built up based on the electromagnetic theory. That is, the RCS of medium surface is computed with Physical Optics, and the RCS of an impedance wedge is computed with the geometrical theory of diffraction.3. Based on the multi-objective optimization theory, the optimization design models on the radar absorbing painting and spray positions are built up after a series of the design variables, objective fuctions and design constrains have been determined.4. In order to validate the practicability and applicability of the optimization design system, several representative fighters are researched as an example, and the satisfying result is acquired.