Computational Optimization of a Low Reynolds Number Inflatable Airfoil

The practical application of inflatable wing sections has been demonstrated on multiple unmanned flights in recent years. Chambered inflatable airfoil designs naturally yield a surface that is inherently bumpy, as the center of each chamber expands further compared to its edges where the interior baffles connect to the surface. Based on inflatable designs used by the Big Blue project at the University of Kentucky, there have been a series of computational studies of the inflatable airfoil shapes to gauge the effects of the bumpy surface versus a smooth airfoil. However, the emphasis has been to analyze the existing airfoils that were constructed without significant analysis of how the undulating surface affected the aerodynamics. This paper attempts to look at whether an improved aerodynamic design can be achieved while maintaining the natural bumpy surface through computational simulation combined with genetic algorithms and surrogate-based modeling. This analysis has so far revealed trends and tendencies that can be applied to subsequent development of these inflatable airfoils.

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