Acoustics: Sound Fields, Transducers and Vibration, 2nd Edition

14.10. Radiation from a circular membrane without a baffle—analytical model of an electrostatic loudspeaker coupled to its surrounding air [3]

In this section, we will introduce the concept of fluid–structure coupling. So far, we have only considered sound radiation from a pure pressure source in free space as if the uniform electrostatic force were driving the air particles directly without any structure, as described in Section 13.8 under the heading “Radiation from a resilient circular disk without a baffle”. However, a real membrane has mass and stiffness, because of its tension, as well as the boundary condition of zero velocity at its perimeter where it is clamped. Without this boundary condition, the velocity of the resilient disk was ...