Computational analysis of palatal non-apneic snoring sound generation using a simplified human upper-airway model

Snoring is a common sleep-related sound phenomenon arising from vibration of upper-airway soft tissues during sleep and occurs both in individuals with obstructive sleep apnea and in a large population with habitual non-apneic snoring. In this study, a two-way coupling, three-dimensional fluid–structure interaction model of the human uvulopalatal system is developed under physiological conditions using simplified geometries. This study investigates the sound-generation mechanisms of palatal non-apneic snoring through two primary objectives: (1) to examine how pulsating breathing flow affects flow patterns, acoustic sources, and soft-palate vibrations and (2) to estimate the strength of these sources. Within the present simplified non-apneic, patent-airway model, results identify the dipole acoustic source as dominant, though monopole contributions remain relevant. Both source types exhibit a strong dependence on the breathing flow, whereas the quadrupole source is negligible at the low Mach number considered. A nonlinear dynamic analysis of the soft-palate motion demonstrates a self-sustained limit-cycle oscillation, confirming that the present in silico soft-palate model operates within a snoring-like regime.