Expected start Date: October 2025
Project Overview:
This engineer position is part of a larger project focused on understanding and simulating the behaviour of cavitation bubbles near biomedical surfaces, such as kidney stones [1, 2]. In treatments like lithotripsy, cavitation bubbles form due to shock waves and undergo violent oscillations and collapses, producing high-speed jets that impact nearby surfaces. These interactions are crucial in medical and industrial applications but pose significant modelling challenges due to the complex physics involved, such as phase change and viscoelastic solids [3].
The selected candidate will contribute to the development of ECOGEN (https://code-mphi.github.io/ECOGEN/), an open-source CFD software designed for compressible multiphase flows [4]. ECOGEN is written in C++ and employs finite volume schemes, specifically Godunov-type schemes with Riemann solvers to determine fluxes. The objective is to enhance ECOGEN’s ability for high-performance computing (HPC) simulations of cavitation bubble dynamics near kidney stones.Engineer objectives:
The primary objectives of this position include:
- Implement HDF5 format for output.
- Implement Lagrangian probes for tracking solid displacement.
- Improve efficiency of ordinary-differential-equation (ODE) solvers, eventually through machine-learning algorithms and/or OpenMP parallel computing.
- Improve AMR load balancing for high-performance computing (HPC) simulations.
- Collaborating with other project members working on fluid and solid material modelling and HPC.
Candidate Profile:
- Master’s degree (M2 level) or PhD degree in mechanical engineering, applied mathematics, informatics or a related field.
- Experience in software and numerical development.
- Experience in HPC and/or machine-learning algorithms.
- Proficiency in object-oriented programming (C++ programming is a plus).
Contact: Kevin Schmidmayer kevin.schmidmayer@inria.fr
References:
[1] Pishchalnikov Y. A., Behnke-Parks W. M., Schmidmayer K., Maeda K., Colonius T., Kenny T. W., Laser D. J. (2019). High-speed video microscopy and numerical modeling of bubble dynamics near a surface of urinary stone. J. Acoust. Soc. Am., 146, 516-531.
[2] Sieber A., Shakya G., Bokman G. T., Belau M., Schlötter M., Kühl A., Lukić B., Schmidmayer K., Supponen O. (2024). Discovering the contribution of cavitation damage in kidney stone ablation through X-ray high-speed imaging and microtomography. 12th International Cavitation Symposium, CAV2024, Chania, Greece.
[3] Ndanou S., Favrie N., Gavrilyuk S. (2015). Multi-solid and multi-fluid diffuse interface model: Applications to dynamic fracture and fragmentation. J. Comp. Phys., 295, 523-555.
[4] Schmidmayer K., Petitpas F., Le Martelot S., Daniel. E. (2020b). ECOGEN: An open-source tool for multiphase, compressible, multiphysics flows. Comp. Phys. Com., 251, 107093.
