Change The Management Structure Of The Credibility Of The Model Optimization Methods Applied Research

In aircraft design aerodynamic characteristic is an important aspect that affecting aircraft performance. Aerodynamic configuration is one of the most important aspects of aircraft design. This thesis discusses the application of Approximation Management Frame-work (AMF) in airfoil optimization design and aircraft aerodynamic configuration optimization design.Approximation Management Framework is a model management framework that based on trust region method, and it aims to construct an optimization method that based on different models. Because this framework provides an effective management on variable-fidelity models, it tries to utilize the advantages of variable-fidelity models . It improves the optimization efficiency under certain design precision request.This thesis analyses the mathematic basis of Approximation Management Framework, the trust region method. According to the consistency condition of low-fidelity model and high-fidelity model, this thesis constructs two low-fidelity model correcting method: first order model and approximate first order model; It discusses the relationship of high-fidelity model, low-fidelity model and approximate model, and it gives a flow chart of AMF method. It combines the AMF that based on first order mod-el with gradient searching algorithm and constructs gradient-based AMF method; It combines the AMF that based on approximate first order model with genetic algorith-m and constructs genetic-based AMF method.Aiming at characteristics of representative aircraft configurations, the commonness and speciality of different kinds of aircraft configuration are investigated. According to the basic elements constitute the aircraft configuration, wing (planform and airfoil) and body (fuselage shape), the mathematic model of parametrization aircraft geometry which described the aircraft configuration is built and the rule of deciding geometry control parameters and design variables is established. It also studies the application of NURBS method in parametrization of aircraft geometry.According to forenamed methods, an optimization design system that based on AMF is built. Gradient-based AMF method is demonstrated on a 2D foil optimization problem. In this case, N-S equations are taken as high-fidelity model and Euler equations are taken as low-fidelity model. The results indicate that one time of time saving is achieved. Genetic-based AMF method is demonstrated on the aerodynamic configuration optimization of an uninhabited aerial vehicle. In this case, Euler equations are taken as high-fidelity model and Green method is taken as low-fidelity model. A very good result is achieved. These numerical experiments validate the practicability and applicability of the system. Some preliminary results are obtained.