The efficiency of any rotational piezoelectric vibration energy harvester (RVEH) can be improved by redesigning its host beam and making provision for self-tuning the harvester’s natural frequency with the rotational driving frequency. This article presents the design and analysis of an exponentially tapering width RVEH. The parameters for the proposed harvester’s natural frequency characteristics are acknowledged, and their effects on the peak open-circuit (OC) voltage response are discussed. A mathematical model of the system is formulated using the Euler-Bernoulli beam theory and Hamilton’s principle. Galerkin’s technique is used to acquire the system’s mass normalized mode shapes in matrix form. The proposed mathematical model is verified through ANSYS Mechanical APDL simulations and experimental methods. The harvester’s responses are obtained through MATLAB code. The two types of parameters that modify the harvester’s fundamental frequency are identified and analyzed. The proposed harvester delivered an improved power density (PD) of 5.27 [Formula: see text] and a performance amplification factor (PAF) of 3.14, operating at 7.968 Hz.

This research work is concerned with the static and dynamic stability study of an exponentially tapered revolving beam having a circular cross-section exposed to an axial live excitation and a variable temperature grade. The stability is analysed for clamped-clamped, clamped-pinned, and pinned-pinned end arrangements. Hamilton’s principle is used to develop the equation of motion and accompanying end conditions. Then, the non-dimensional form of the equation of motion and the end conditions are found. Galerkin’s process is used to find a number of Hill’s equations from the non-dimensional equations. The parametric instability regions are acquired by means of the Saito-Otomi conditions. The consequences of the variation parameter, revolution speed, temperature grade, and hub radius on the instability regions are examined for both static and dynamic load case and represented by a number of plots. The legitimacy of the results is tested by plotting different graphs between displacement and time using the Runge-Kutta fourth-order method. The results divulge that the stability is increased by increasing the revolution speed; however, an increase in the variation parameter leads to destabilization in the system and for same parameters, the stability is less in the case of a variable temperature grade than that of a constant temperature grade condition.

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