Numerical Simulation of Volcanic Jets

Marica Pelanti (1) , Randall J. Leveque (2)

1 ENSTA Paris - École Nationale Supérieure de Techniques Avancées
2 University of Washington [Seattle]

We numerically model the dynamics of explosive volcanic eruptions to study the fluid-dynamic structure of jets that develop in such processes. The eruptive mixture is described as a two-phase flow made of gas and solid particles. The hyperbolic portion of these equations consists of the compressible Euler equations for the gas phase and the non-strictly hyperbolic conservation laws for a pressureless dust, used to model the solid phase. These equations are coupled together through terms modeling inter-phase drag and heat transfer. Gravity is also taken into account for both phases. Ejection velocities in eruptions are often large enough that the jet is supersonic relative to the mixture sound speed, leading to the development of internal shock wave structures. We solve the system of equations by employing a high-resolution finite volume method based on wave propagation algorithms.

Domaines: Modélisation et simulation; Volcanologie

Marica Pelanti, Randall J. Leveque. Numerical Simulation of Volcanic Jets. Tenth International Conference on Hyperbolic Problems (HYP2004), Sep 2004, Osaka, Japan. ⟨hal-01342312⟩