Hello,

I am looking at the frequency domain of an acoustic simulation in a spherical cavity and having some issues producing the first fundamental frequency: f = c/(2r) where c is the speed of sound inside the cavity and r is the radius of the sphere. Instead, the frequencies I get are f = c/r and all of its harmonics.

Curiously, running the simulation in 2D (circular cavity) gives the expected frequencies. I have also tried using linear propagation only (by not setting BonA) and surrounding the sphere with air so that an entire wavelength of the expected frequency should fit in the media but I still produce only f = c/r and its harmonics instead of f=c/(2r) and its harmonics.

Any help would be very much appreciated,

PC