Phd position in Partially Immersed Granular Collapse: from Grain Mechanics to Tsunami Dynamics

The project explores wave generation caused by the collapse of a granular column in a fluid, using a powerful combination of experiments and DEM–FEM coupled simulations. A great fit for anyone passionate about granular mechanics, fluid–particle interactions, and computational modeling, with links to real-world geophysical hazards. Numerical part For this thesis, a recent innovative numerical approach developped in the MigFlow software (Fig. 1 bot tom right) will be used [4]. This open-source software combines a Nonsmooth Discrete Elements Method (DEM-NSCD) for the granular phase to a Particle Finite Elements Method (PFEM) for the fluid phase. While the DEM provides insights on the grain-scale physics, the PFEM enables the reliable simulation of a free surface. It will be necessary to extend this model, adding key micromechanical aspects such as contact lubrication or capillarity, with a focus on code optimisation to minimise computational costs. Experimental part In order to assert the reliability the numerical results, an important aspect of this work will be the experimental validation in direct collaboration with TU Delft. In that view, a research stay is strongly considered. Their static liquefaction tank (Fig. 1 top left) and physical modeling facilities enable the study of mass movements, measuring quantities such as pressure, velocity and acceleration, notably with Particle Image Velocimetry (PIV). Candidate profile Overall, this thesis offers the opportunity to leverage skills in both the numerical and experimental aspects of research focused on immersed granular materials. Therefore, the candidate should have a strong interest in the development and use of numerical methods, as well as an appetite for experimental approaches. Required skills include Python and C++ in terms of coding, as well as a good knowledge of fluid mechanics. Knowledge of granular mechanics is a serious plus, but is not mandatory. Supervision This thesis is offered within the framework of the I2S Doctoral School. Its funding depends on the candidate’s success in an audition conducted by a jury of the Doctoral School. The PhD is proposed in the ”Laboratoire de M´ecanique et G´enie Civil” (LMGC) under the supervision of: Mathieu Renouf, Charg´e de Recherche, HDR. LMGC CNRS. mathieu.renouf@umontpellier.fr Nathan Coppin, Maˆıtre de Conf´erences, LMGC. nathan.coppin@umontpellier.fr Miguel Cabrera, Assistant Professor, TU Delft. m.a.cabrera@tudelft.nl For any further information, please contact Nathan Coppin