Effect of periodic metamaterial structures with different arrangement patterns on the effectiveness of hydroelastic energy harvesters: Computational investigation

Abstract

This study introduces the concept of periodic metamaterials to determine an optimal arrangement for performance enhancement of flow-induced vibration energy harvesters. Three two-dimensional metamaterial structures including four-interference, six-interference, and eight-interference cylindrical structures are computationally explored and discussed. The displacement of the cylinder is calculated by a user-defined function based on the fourth-order Runge-Kutta algorithm. The computational simulation is set under a low Reynolds number region (64 ≤ Re ≤ 388), and the increase of Reynolds number is controlled by the reduced velocity (2 ≤ U* ≤ 12). It is found that the output harvested power of the three metamaterial structures is more significant than the single-cylinder system. The four-interference cylindrical structure shows both maximum output power of 2.4 μW when U* = 5, and good suppression when 10 ≤ U* ≤ 12. Besides, the six-interference cylindrical structure shows a trend of “advance” and the eight-interference cylindrical structure displays “beating” when U* = 9 and 10. In the comparison scheme of reducing the radius, the dimensionless amplitude of the metamaterial scheme is still larger than that of the single-cylinder scheme, however, the property of expanding “lock-in” has not been found. This study shows the possible advantages and disadvantages of considering metamaterial structures to enhance the effectiveness of flow-induced vibration energy harvesters.