Analysis of active PVDF-paper/fabric speaker for Active Noise Control

Abstract

Knitted fabrics can be made to vibrate as a speaker by laminating it with Polyvinylidene fluoride (PVDF) strips to form curved arch laminated at the ends. The PVDF strip would vibrate due to the piezo electric effect when a 200 Vrms voltage is applied.A two-dimensional analytical prediction model is created based on the principles of stress and strain behaviour of a curved laminated arch. The model predicts the radial displacement of the arch with respect to the frequency of the excitation voltage of the PVDF strips. The Sound Propagation Level (SPL) at a particular point from the arch surface is modelled as a simple sound source in an infinite baffle. The acoustic pressure is linked with the radial displacement in the model. Simulation is carried out on structural properties of the fabric to discern the resonance region of the speaker vital for Active Noise Control to reduce automotive interior noise.