Optimized design of tidal current turbine blade at low current rate

Blades have a significant influence on a tidal current turbine (TCT) ’s energy transfer capacity. In order to ensure a blade working safely and efficiently in low flow rates, a special design is needed. Hydrofoil’s shape and blade’s quality are the key factors which affect blade’s dynamic and starting performance at low flow rate. In this research, basing on a 500 WORI blade (an initial design of 500 W tidal turbine’s blade), optimizations of hydrofoil and blade structure were done sequentially by genetic algorithm. After hydrofoil optimization we got optimized hydrofoil OPT₂4 which has high dynamic performance, good startup performance and durable structure, then redesigned the shape of new 500 WOPT blade (a 500 W tidal turbine’s blade using optimized hydrofoil). After that, the structure of 500 WOPT blade was designed empirically and optimized to reduce its weight. Both 500 WORI and 500 WOPT were fabricated, and their efficiency and the structure strength were tested. The experimental results show that the strain of the 500 WOPT blade is smaller than that of the 500 WORI blade under the same load. The power efficiency of the 500 WOPT at the optimal tip speed ratio is increased 500 WORI by 46. 1%, and 500 WOPT was able to start at the flow rate of 0. 5–0. 6 m/s.