Mechanical and Civil Engineering Seminar

Mechanical and Civil Engineering Seminar Series

Title: Advances in Eulerian Modeling: Compaction, Multiphase Flow, and Plasticity

Abstract: The Eulerian framework for computation offers two main advantages. First, it eliminates the need for mesh evolution and remeshing when mesh distortion becomes excessive, simplifying the computational process. Second, the flow rules for plasticity problems are more naturally expressed within this framework. However, significant challenges remain, particularly in solid mechanics. Complex solid mechanics models often require objective derivatives, but the choice of these derivatives is not always clear. Additionally, enforcing interface conditions can be challenging. This talk addresses these issues. A new model for kinematic hardening in a Eulerian context, which avoids the need for objective derivatives, will be presented. This formulation is compatible with both Lagrangian and Eulerian frameworks. Recent advances in multiphase flow modeling will also be discussed, including shock layers in porous materials, relaxation parameters for cavitating bubble simulations, and extending solid-fluid models to generalized standard materials. Results on spalling and fragmentation in porous titanium will be highlighted. Finally, perspectives on coupling multiphase flow approaches with gradient damage models will be explored.

Bio: Nicholas Favrie is an Associate Professor at Aix-Marseille University, specializing in computational physics, hyper elasticity, plasticity, and Godunov-type schemes. His research addresses extreme deformation modeling, focusing on solid-fluid interactions, non-local models such as damage, surface tension, and microinertia. He also works on multiphase models for granular and porous materials under dynamic loading. His expertise spans continuum mechanics, thermodynamics, fluid and solids mechanics, and the numerical simulation of complex phenomena. Nicolas is renowned for developing innovative mathematical models and efficient numerical methods to tackle challenging problems in solid and fluid mechanics, bridging theoretical advances with practical applications in applied mathematics and engineering.

NOTE: At this time, in-person Mechanical and Civil Engineering Lectures are open to all Caltech students/staff/faculty/visitors.