Several studies have focused on experimental techniques to determine the attenuation of hearing protectors when subjected to high-intensity impulse noise and where, for reasons of safety, it is not feasible to use human test subjects. Based on a simplified geometry of the human ear, it is possible to model external ear canal and earmuff conveniently within the normal hearing frequency range using the finite element method (FEM). The acoustic impedance characteristics of the walls of the ear canal and eardrum are taken into consideration in the model. Temporal excitation is based on short duration high-intensity sound pressure pulses obtained from experimental tests using the shock tube technique. The results indicate that the geometry and material properties of the protector are influential on the rise time and peak sound pressure of the transmitted pulse. This FEM model can provide valuable information about the characteristics of earmuffs and permit the manufacturer to optimise earmuffs for maximum comfort and attenuation.
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