Numerical investigations of two-phase finger-like instabilities

Alexandre Chiapolino (1) , Richard Saurel (1)

1 LMA - Laboratoire de Mécanique et d'Acoustique [Marseille]

The aim of the present work is to progress in the identification of the effects responsible for the formation of jets in heterogeneous gas-particle cylindrical and spherical explosions. In this direction three two-phase flow models are considered, namely Baer and Nunziato's (BN) (1986) model, Marble's (1963) model and the dense-dilute model of Saurel et al. (2017). The first and third ones involve both non-conservative terms and viscous drag effects while the second one involves viscous drag only as interaction force. Computed results show that viscous drag alone is unable to reproduce finger-like instabilities. The BN model and the dense-dilute one differ significantly by their acoustic properties. It is shown that the only model able to reproduce qualitatively finger-like jets is the dense-dilute model. Mesh dependence of the results is studied as well as presence or absence of viscous drag. It appears that the non-conservative terms seem responsible for jetting effects.

Mots clés: hyperbolic; particle jets; explosions

Domaines: Mécanique des fluides [physics.class-ph]; Milieux fluides et réactifs; Equations aux dérivées partielles [math.AP]; Thermique [physics.class-ph]

Alexandre Chiapolino, Richard Saurel. Numerical investigations of two-phase finger-like instabilities. Computers and Fluids, 2020, 206, pp.104585. ⟨10.1016/j.compfluid.2020.104585⟩. ⟨hal-02416883⟩