Environment coupled piezoelectric galloping wind energy harvesting

Abstract As a stable limit cycle oscillation occurred after subcritical Hopf bifurcation, galloping was preferred in scattered wind energy harvesting. For practical applications across seasons and regions, environmental adaptability of galloping piezoelectric energy harvester on atmospheric temperature and wind speed is investigated. A multi-field coupled geometric and aerodynamic nonlinear distributed-parameter model is established. The method of multiple scales is used to derive the analytical solutions of the nonlinear coupled continuous model. Wind-tunnel tests of the piezoelectric galloping energy harvesters are performed for model validation. The empirical coefficients of nonlinear piezoelectric parameters varied by the temperature are identified. The optimal load resistance tailored for the atmospheric temperature and airflow speed is determined. With the environment adaptable load resistance, the onset speed of energy harvesting is minimized to be lower than 1 m/s for the galloping to occur. High temperature benefits galloping energy harvesting begin at low wind speed. Excellent environmental adaptability of the piezoelectric galloping energy harvester is realized in atmospheric temperature of −40 °C to 50 °C and breeze to gale wind speed of 1-24 m/s.