Sound pressure distributions and propagation paths in the vocal tract with the pyriform fossa and the larynx

We have constructed models /i/ and /u/ of the vocal tract from the glottis to the velum with the pyriform fossa and the larynx, and have analyzed by finite element method. Sound pressure distributions in XY cross-sections at 500Hz, the first resonant frequencies, and 2500Hz are shown. The barycentric coordinates of real part of the sound intensity and of sound particle velocity in each XY cross-section are shown. It is found that sound in the vocal tract is not always propagated as a plane wave even when its frequency is low such as 500Hz. Paths of sound propagation are shown. We show the reason why the first resonant frequencies are different in the vocal tract with and without the pyriform fossa.