Enhancing tidal current turbine efficiency through multi-biomimetic blade design features

To achieve an efficient tidal current turbine (TCT), the impact of three biomimetic trailing edge designs (i.e., slabbing, slab-toothed, and serrated), a blade configuration design (i.e., sweep design) and their various combinations on TCT's power coefficient are numerically and experimentally studied in this paper. The novelty of this paper lies in its pioneering exploration of the synergistic effects of multiple biomimetic designs on the TCT's power generation and start-up performance, as well as the interplays between the sweep design and biomimetic trailing edge designs. Both numerical simulations and experimental studies provide compelling evidence that all three biomimetic trailing edge designs enhance the blade's energy capture efficiency. For example, at a 7° angle of attack, the lift-to-drag ratio for the slabbing trailing edge blade increases by 12.124% and the slab-toothed trailing edge blade increases by 11.770% compared to the standard blade. The incorporation of sweep design and biomimetic trailing edge design produces a further enhancement in both the TCT's power generation and startup performance. In particular, the simultaneous implementation of slabbed trailing edge design and sweep design makes the power generation efficiency of TCT increase by up to 54.72% when compared to TCTs using standard straight blades.