Stochastic analysis for vortex-induced vibration piezoelectric energy harvesting in incoming wind turbulence

Utilizing vortex-induced vibration piezoelectric energy harvesters (VPEHs) to capture wind energy from the environment to power sensors is a prospective technique. Most of the scholars in previous studies only take into account the uniform wind, i.e., they take the average value of wind turbulence, ignoring the effect of the pulsation component in a practical wind environment. This may result in an inability to predict correctly the working performance of the VPEHs in real environments. To solve this problem, we establish a stochastic analysis method for the VPEHs based on the probability density evolution method (PDEM). The lift and the drag coefficients are assumed to be random variables. Subsequently, the random responses of the VPEHs in different incoming wind turbulence situations are investigated by numerical analysis and wind tunnel experiments. The results show that the confidence intervals and the probability density distributions computed by the stochastic analysis method can reflect the characteristics of the VPEH's random response in turbulence. Finally, a reliability design research exploration of the VPEHs in turbulence is carried out based on the stochastic analysis approach. The stochastic analysis method established in this study provides new insights for predicting the working performance and optimizing the design of the VPEHs in the practical environment.