Electroacoustic Absorbers Based on Passive Finite-Time Control of Loudspeakers: A Numerical Investigation

This paper proposes a numerical investigation of a controlled loudspeaker designed to absorb acoustic plane waves at a duct termination. More precisely, a nonlinear control for a current-driven loudspeaker is presented, that relies on (1) measurements of velocity and acoustic pressure at the membrane, (2) a linear electroacoustic loudspeaker model and (3) a nonlinear finite-time control method. Numerical tests are carried out by a passive-guaranteed simulation of the loudspeaker dynamics in the port-Hamiltonian systems formalism. The sound absorption efficiency is evaluated up to 300 Hz by computing the reflected pressure at the membrane. The results are compared with a similar control architecture: the finite-time control for sound absorption proves effective, especially in the low frequency range.