Cfd-Based Aerodynamic Shape Optimization Method Investigation On A Civil Aircraft Wing-Body Fairing

The CFD-based aerodynamic design using Navier-Stokes plays an important role in the detailed aerodynamic shaping of complex surfaces on civil aircraft. The research is focused on the aerodynamic shape optimization of civil aircraft wing-body fairing using consistent parameterization, response surface modeling and numerical optimization methods.A review on CFD-based aerodynamic optimization, general CFD techniques and free form curve and surface modeling methods is presented first. Challenges associated with civil aircraft aerodynamic shape optimization process is analyzed. Base on these analysis and specific engineering requirements related to wing body fairing design, a free form parametric modeling method based on B-spline is proposed and implemented within CATIA; To improve the efficiency of the complete optimization process, a genetic algorithm facilitated by response surface method is applied to the problem. Results shows that the design method adopted is effective in solving the problem of complex shape optimizations using computational expensive CFD codes. The advantages of the proposed method lies not only in the flexibility wing-body fairing modeling, but also in its capability to adapt quickly to the evolution of design requirements during the design process. The drag coefficient is reduced by 2.21% for the design condition. The method proposed can be used in a wider context of complex aerodynamic shape design.