Aerodynamic/Structural Multidisciplinary Design Optimization Of Wings Based On CAD

Since aircraft design involves many disciplines, the multidisciplinary design optimization (MDO) of the aircraft has been an important field. For recent decades, the analysis model of each discipline gets increasingly detail, and the fidelity of the codes and software developed based on those analysis models become higher. Accordingly, more accurate geometric models are required. On the other hand, CAD software shows great advantage in geometric modeling. It is expected that the combination of CAD tools with the high fidelity models of each discipline will enhance the performance of MDO of the aircraft.A process synthesizing CAD model into the MDO framework for wing aerodynamic/structural multidisciplinary design optimization was proposed in this thesis. The model generator for multidisciplinary analysis and optimization was a critical element in aircraft MDO. The model generator had two functions: one function is to generate a common geometric model of aircraft automatically using the primary parameters; another function is to extract the models for disciplinary analysis and optimization from the common geometric model. The model generator was developed using CATIA software API and was used to automatically generate the parametric models which provide unified models for the aerodynamic and structural analysis of wings. In the environment of the optimization software iSIGHT, the model generator was used as a bridge to integrate both aerodynamic and structural high fidelity analysis tools to construct the MDO process. And the whole MDO process was accomplished automatically.The first example was a business jet wing design problem which was used to illustrate the parametric modeling method of wings in detail. The MDO process was applied to solve the problem of aerodynamic/structural multidisciplinary design optimization of the wing of the business jet. The feasibility of the MDO process was verified by the example. The second example was a more complicated wing design problem - the wing design of a regional airliner. In this problem, the MDO process was refined to account for more complicated design problem. Again, the feasibility and efficiency of the process was verified. The study of the two examples manifested that the CAD based MDO process proposed in this thesis can be applied to aerodynamic/structural multidisciplinary design optimization of wings.