Pemodelan Galloping Sebagai Media Energy Harvester Dengan Tipbody Berbentuk Triangular Menggunakan Piezoelectric

Abstract

Aeroelastic is a physical phenomenon involving the interaction of inertia, elastic and aerodynamics forces. One of the classic aeroelastic instability phenomena often encountered is galloping, where the occuring vibrations can be characterized by its low oscillation frequency and large amplitude. Due to the large amplitude of oscillations, galloping can be an acceptable scenario for vibrating piezoelectric-based energy harvesters. In its application this energy harvesting device is manifested as a cantilevered beam with a tip mass at its free end. The oscillations, arising from the interaction with the fluid flow through it, occur in the normal plane of the direction of the wind flow. On the cantilevered beam a piezoelectric is attached, which due to the dynamic strain the electrical energy can be extracted from mechanical energy. In this study, a theoretical model was developed to predict the dynamic characteristics of an energy harvesting system with a triangular-aerodynamic body. The FEM procedure is applied to determine the natural frequencies and mode shapes of the structure. In addition, the induced galloping force is modeled using the quasi-steady approximation. For this purpose, lift coefficients and aerodynamic body drag forces for certain Reynolds numbers and various angles of attack are determined using a computational fluid dynamics procedure (CFD). The dynamic response of the harvester can then be obtained directly by solving differential equations representing the transverse movement of the energy harvester. From the obtained results shows that the simulation developed in this study provides a maximum output voltage that differ about 1% compared to the output voltage obtained from the test. In this study, a variation of Reynolds number, weight of the tip mass and the resistance is also conducted