抄録
The relationship between optimized blade airfoil shape and effect of flow interaction between blade airfoils is studied on a small, straight Darrieus type vertical axis wind turbine (VAWT). To compare Pareto optimal blade airfoil shapes, a multi-objective shape optimization is performed using a surrogate model-based global optimization approach. The objective functions are the performance of VAWT at one and three blade(s) conditions. These conditions correspond to the cases with and without the flow interaction effect between blade airfoils. The performance is evaluated by 2D unsteady incompressible computational fluid dynamics simulations using ANSYS Fluent. The Pareto optimal airfoil shape at the one blade condition has a thin trailing edge while that at the three blades condition has a thicker airfoil with a rounded outer surface. The rounded airfoil reduces the performance due to spoil higher pressure on outer surface. On the other hand, it also reduces the effect of the wake. It leads to the improvement in the performance with other blade airfoils and the rounded airfoil has best performance as a whole rotor.
