Aerodynamic modelling and optimization of morphing wings

Körpe, Durmuş Sinan
This thesis deals with aerodynamic optimization of morphing wings under performance and geometric constraints. In order to perform the optimization process, flow solvers computing aerodynamic lift and drag were developed as a function evaluator. A gradient based optimization method was used in order to develop the optimization algorithm. Three dimensional panel method solver was developed in order to obtain lift, pressure drag and induced drag values for a finite wing. Obtained results were compared with different solvers. Compared results were in agreement for low to moderate angles of attack. Two dimensional boundary layer solver was developed in order to obtain the skin friction drag for each strip along span. The boundary layer results were compared with another solver for different angle of attack values and agreement in the results was observed at low to moderate angle of attack values. Optimization solver was developed by using the generalized reduced gradient method. A benchmark structural optimization problem was solved by using this solver and results were compared with the results in the literature. Morphing wing optimization process started with a fixed wing optimization problem for a certain cruise velocity at steady level flight for the baseline wing. Fixed wing optimization was performed for three cases that are only airfoil shape change, only planform change and combined airfoil shape and planform change. After that it was assumed that materials and mechanisms for morphing that were used for another study in the literature were available and the morphing optimization problem was defined according to them. Similar to fixed wing optimization, the process was performed for only airfoil shape change, only planform change and combined airfoil shape and planform change. The optimization problem was solved for velocities less and greater than the cruise velocity and drag polar curve of the morphing wing was obtained. According to the results, remarkable drag reductions were obtained that is expected from a morphing wing. Nevertheless, drag reductions obtained with only planform morphing are significantly higher than those obtained with only airfoil shape morphing.


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Citation Formats
D. S. Körpe, “Aerodynamic modelling and optimization of morphing wings,” Ph.D. - Doctoral Program, Middle East Technical University, 2014.