Energy harvesting is a burgeoning eco-friendly technology that goes beyond traditional sources such as solar and wind power. Recent research has delved into generating electricity from unused or discarded energy in daily life, such as vibrations from passing car engines or trains. A team of researchers from Pohang University of Science and Technology (POSTECH) and Sungkyunkwan University (SKKU) collaborated on a project to enhance energy harvesting efficiency using a unique type of metasurface resembling LEGO bricks, allowing for practical applications.
Metamaterials, artificially designed structures that manipulate wave energy like light, vibration, and sound, play a crucial role in energy harvesting by gathering elastic waves in piezoelectric components to increase electricity production. However, the conventional Euler-Bernoulli beam theory limits the practical application of metamaterials to a single frequency, posing challenges for real-world use. The research team overcame this limitation by employing the Timoshenko-Ehrenfest beam theory, which considers fundamental characteristics of elasticity like shear deformation and rotational inertia effects in the beam.
The researchers successfully interpreted and modeled elastic metamaterials for phase modulation of elastic waves using the Timoshenko-Ehrenfest beam theory. They developed a new type of reconfigurable elastic metasurface capable of attaching and detaching multiple structures, enabling control over various wave phenomena across a wide frequency range. This metasurface, known as TREM, demonstrated exceptional effectiveness in harvesting elastic wave energy, boosting the electrical output power of piezoelectric components significantly.
Lead researcher Professor Junsuk Rho believes that their newly developed metasurface, designed to operate across multifunctional and wide-frequency ranges, has promising applications in energy harvesting, structural health monitoring, wireless sensing, and the Internet of Things. The technology holds immense potential for significant contributions across diverse fields, making it valuable for eco-friendly utilization of ambient energy. The work was supported by the N.EX.T. Impact Project of POSCO Holdings, as well as funding from various programs administered by the National Research Foundation of Korea and funded by the Ministry of Science and ICT of the Korean government.
In conclusion, energy harvesting technology is rapidly advancing to tap into unused or discarded energy sources in daily life, expanding beyond traditional solar and wind power. The collaborative research by a team of researchers from POSTECH and SKKU has led to the development of a new type of reconfigurable elastic metasurface that significantly enhances energy harvesting efficiency. By utilizing the Timoshenko-Ehrenfest beam theory to model elastic metamaterials and develop the TREM, the researchers have demonstrated the potential for this technology to revolutionize energy harvesting and have applications in various fields. With support from the Korean government and industry partners, this research paves the way for sustainable and eco-friendly energy solutions in the future.
