Multi-objective Aerodynamic Design Optimization of a Flying Wing using Surrogate Model

A multi- point and multi- objective aerodynamic design optimization which simultaneously considering the taking- offperformance and cruise performance of a flying wing is studied in this research. In the optimization procedure,the flow around the wing is simulated using the RANS solver; the planform shape,section shapes,and twist angle of section shapes are taken as design variables,which results in 58 design variables in total; maximizing the lift coefficient at taking- off condition and the lift- to- drag ratio at cruise condition are taken as the two objectives,while the moment coefficients at the two operating conditions are taken as constraints,and the planform area as well as the thickness of sections are also taken as constraints. Although there are a large number of design variables,a good Pareto optimal front is obtained with a small number of candidate design evaluationby the use of surrogate model and a sequential updating strategy. The performance of a shape arbitrarily selected from the Pareto front is checked and compared with the baseline,it shows that the optimized shape outperforms the baseline at the concerned conditions with all the constraints fulfilled.