Experimental analysis and estimation of vibration frequency for airflow-induced vibration piezoelectric generators

To address the inadequacy of existing empirical formulas for estimating the vibration frequency of small airflow-induced piezoelectric generators, this study proposes a novel method for vibration frequency estimation specifically tailored to such generators. Through experimental analysis of vibration frequencies, the current expression for vibration frequency is modified to enhance the accuracy of frequency estimation for short resonators. The results indicate that the length of the resonator is the primary influencing factor. As the length increases, the frequency decreases, demonstrating an inverse relationship. The distance between the nozzle and the resonator is regarded as a secondary factor. Although there is a slight decrease in frequency as the spacing increases, its impact remains limited. Furthermore, the discrepancy between the theoretical values derived from the modified empirical frequency formula and the experimental data does not exceed 4 %, and the coefficient of determination ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mrow> <mml:mi>R</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msup> </mml:math> ) for the modified empirical formulation is 0.9987, highlighting its reliability as an effective method for estimating vibration frequency. These conclusions may offer guidance in designing the vibration frequency and identifying essential structural parameters.