Training | Computational Fluid Dynamics | Combustion, Computational Fluid Dynamics, Electromagnetism, High Performance Computing
Required Education : Master
Start date : 1 February 2024
Mission duration : 6 mois
Deadline for applications : 1 January 2024
Salary : 650€/mois
Context
Numerous initiatives are presently in progress to utilise carbonised fuels, such as hydrogen (H2) and ammonia (NH3), as energy carriers in response to the climate crisis. These fuels can be produced using intermittent energy sources (wind, solar, etc.), serving as a form of storage and can be used in a controlled manner. However, using these new fuels in current combustion chambers is not immediately possible and requires an adaptation phase to meet safety and pollutant emission standards, such as NOx. To achieve this, it is natural to move towards lean combustion regimes, unfortunately prone to instabilities and more difficult to ignite. An emerging solution to these problems is to use Nanosecond Repetitively Pulsed discharges. This type of discharge is known to be able to mitigate instabilities encountered in combustion chambers and is also effective for ignition, with low electrical power compared to that of the flame (<1%).
Mission
The objective of this internship is to perform detailed plasma discharge simulations. To do this, the candidate will use the AVBP code (http://www.cerfacs.fr/avbp7x) and its plasma extension [1] to perform detailed calculations of NRP discharges in a flowing environment. This kind of simulation is highly challenging regarding the small structures that have to be captured to describe the discharge. Moreover, NRP discharge simulation involves a large range of timescales, from nanosecond to millisecond. Thus, numerical techniques have to be developed to reduce drastically the simulation cost. One of them is the Adaptive Mesh Refinement (AMR) which consists in refining only very specific zones, the remaining domain being coarsened. This method has been widely applied in other applications such as aerodynamics and reactive flow [2] (see Fig. 1). However, this has to be adapted to plasma physics, in particular the choice of the metric. First results have been obtained with AVBP to simulate a single 2D discharge with AMR (see Fig. 2). This simple 2D case will help to consolidate the use of AMR in a plasma framework and extend it to a 3D case including a flowing mixture. The objective of this internship is to become familiar with the physics of non-equilibrium plasma discharges.
Work program
- Assimilation of the plasma discharge physics (litterature review).
- Simulation of a discharge using AMR and various metrics to trigger the mesh refinement.
- Simulation of a discharge in a cross-flow
Technical program
- Carry out developments in the Fortran language within the AVBP code with the support of CERFACS researchers.
- Develop and improve pre-processing or post-processing scripts in Python.
A doctoral position (ANR JETHPAC) is funded for September 2024, providing an opportunity for highly motivated candidates to continue to work in the field of plasma-assisted combustion.
Contacts
N. Barléon (barleon@cerfacs.fr)
O. Vermorel (vermorel@cerfacs.fr)
B. Cuenot (cuenot@cerfacs.fr)
[1] L. Cheng, N. Barleon, O. Vermorel, B. Cuenot, A. Bourdon, AVIP: a low temperature plasma code (2022). arXiv:2201.01291.
[2] B. Vanbersel, F. A. M. Ramirez, P. Mohanamuraly, G. Staffelbach, T. Jaravel, Q. Douasbin, O. Dounia, O. Vermorel, A systematic adaptive mesh refinement method for large eddy simulation of turbulent flame propagation (Oct. 2023). doi:10.21203/rs.3.rs-3388018/v1.
