Two analyses are performed:
- Coupled-field static analysis
A large deflection coupled field static analysis is performed to insert tensile stress in the membrane with an applied temperature and to introduce a DC voltage on the membrane side of the air gap. Acoustic elements are ignored in this analysis, but the Element Morphing On under the Acoustics Domain Definition of Physics Region is used to morph acoustic elements so that they are properly shaped for the downstream linear perturbation analysis.
- Prestressed coupled-field harmonic analysis
A frequency sweep is performed from 20 to 20,000 Hz with a logarithmic span option. In this coupled-field harmonic response analysis, the linear perturbation method is used to include prestress effects. A DC bias voltage of 1.5 V is applied. An acoustic velocity is applied on the sound port inlet, which causes the membrane to vibrate.
