Modeling multiphase effects on pressure oscillations in solid propulsion

In this work multiphase effects on pressure oscillations within solid rocket motors are addressed with particular focus on thermoacoustics. A mathematical and numerical approach is described and implemented in an already existing CFD in-house code, taking care of employing the most simplified physical describing tool suite. In order to validate such methodology, numerical simulations have been performed on simplified geometries known in literature to be prone to develop pressure fluctuations due multiphase effects. The presented solutions show actually an instable behaviour, whose thermoacoustic nature is proved by the presence of its characteristics key features and by Rayleigh criterion analysis. Such result ensures the model validation, which is the preliminary and obligatory step of a work-in-progress project aimed to improve the understanding about pressure oscillations in solid rocket motors.