For wind power design, researchers take inspiration from the sea

Wind energy harvester designs consist of only a few primary components — namely, an element that vibrates when it interacts with wind flow, called a bluff body, and a piezoelectric sheet, which converts mechanical strain from this vibration into electrical energy. The bluff body is typically cylindrical, but there is little research into its ideal aerodynamic shape.

Luckily, nature is quite familiar with aerodynamics.

“A video in which the fishtail creates organized vortex patterns to transfer momentum very effectively to the surrounding water for propulsion inspired me to explore a fishtail configuration as a potential wind energy harvester design,” said Xiaoyu Zhang, author on a paper by Zhang et al. which compares fishtail-inspired bluff body designs.

The fishtail design leads to large vortices that enhance pressure fluctuations on the bluff body’s surface, increasing energy transfer from the wind to the harvester. With faster wind, the vortices that form are greater both in number and intensity, leading to more energy capture. A larger afterbody inclination of the fishtail structure —how wide the fishtail flares — also increases the energy transfer.

The researchers conducted simulations with wind speeds ranging from 1-6 m/s. This aligns with real-world applications, where wind speeds for piezoelectric wind energy harvesters are generally below 6 m/s, making them appropriate for low-power applications like wireless sensors and other mobile electric devices.

For further validation of their findings, the scientists plan to fabricate prototypes of fishtail-inspired bluff bodies for experimental testing. They also hope to compare other bio-inspired structures for wind energy harvesting, such as avian forms.

Source: “Performance enhancement of piezoelectric energy harvesters based on flow-induced vibration via bio-inspired design,” by Dong Zhang, Xiaoyu Zhang, Peilun Yin, Cuipeng Xia, Panlong Tan, Physics of Fluids (2025). The article can be accessed at https://doi.org/10.1063/5.0277055 .