Phd Position F - m Time Accurate Anisotropic Mesh Adaptation For Delayed Detached Eddy Simulations H/F INRIA

PhD Position F/M Time Accurate Anisotropic Mesh Adaptation for Delayed Detached Eddy Simulations
Le descriptif de l'offre ci-dessous est en Anglais
Type de contrat : CDD

Niveau de diplôme exigé : Bac +5 ou équivalent

Fonction : Doctorant

A propos du centre ou de la direction fonctionnelle

The Inria Saclay-Île-de-France Research Centre was established in 2008. It has developed as part of the Saclay site in partnership with Paris-Saclay University and with the Institut Polytechnique de Paris .

The centre has 40, 27 of which operate jointly with Paris-Saclay University and the Institut Polytechnique de Paris; Its activities occupy over 600 people, scientists and research and innovation support staff, including 44 different nationalities.

Mission confiée

Numerical simulation has been booming over the last thirty years, thanks to increasingly powerful numerical methods, computer-aided design (CAD), the mesh generation for complex 3D geometries, and the coming of supercomputers (HPC). The discipline is now mature and has become an integral part of design in science and engineering applications. This new status has led scientists and engineers to consider numerical simulation of problems with increasing geometrical and physical complexities. The mesh is at the core of the classical computational pipeline and a key component to significant improvements. Therefore, the requirements on meshing methods are an ever increasing need, with increased difficulty, to produce high quality meshes to enable reliable solution output predictions in an automated manner.

Mesh adaptation is an innovative method for controlling errors in numerical simulations by generating meshes that are adapted to the geometry and physics of the problem being studied. It results in a powerful methodology that reduces significantly the size of the mesh required to reach the desired accuracy. Thus, it impacts favorably the simulation CPU time and memory requirement. Moreover, as the generated adapted mesh is in agreement with the physics of the flow, for some applications, this is the only way to obtain an accurate prediction. In fact, mesh adaptation enables a full control of discretization errors on the geometric model and the solution. Thus, it is a first step in the certification of numerical solutions by the obtention of mesh converged solutions, i.e., providing high-fidelity numerical simulations.

Nowadays, mesh adaptation is a mature tool which is well-posed mathematically [8, 9]. And, as it is fully automatic, it has started to be used in industrial R&D departments (Safran Tech, Boeing, NASA, ...). Indeed, it has already proved, throughout many publications and applications, its superiority with respect to fixed mesh. However, its domain of application is in majority restricted to inviscid steady or unsteady flows. It has been recently extended to turbulent flows for steady problems.

Principales activités

The following schedule is proposed for the 3 years of thesis:

- T0 + 6: Learn how to use the GAMMA project software and environment by running steady RANS and unsteady inviscid simulations using the Inria's mesh adaptive solution platform. Bibliography on error estimate and mesh adaptation for URANS and LES.
- T0 + 18: Development of time-accurate metric-based mesh adaptation platform for URANS. Efficient implicit scheme for unsteady flows (BDF, Dual-Time Stepping, Implicit RK, ...). Space-time error estimate providing the optimal adapted mesh and time-step. Analysis of the accuracy time-accurate metric-based mesh adaptation platform on several unsteady aerodynamics simulations.
- T0 + 24: Development of time-accurate metric-based mesh adaptation platform for LES. Develop a LES scheme which allows mesh convergence study. Error estimate and sensors for LES. Analysis of the accuracy time-accurate metric-based mesh adaptation platform on mixing layer problems.
- T0 + 30: Development of time-accurate metric-based mesh adaptation platform for DDES. Error estimate on the model to specify the modeling regions. Analysis of the accuracy time-accurate metric-based mesh adaptation platform aircraft in high-lift configuration.
- T0+36: Writing the thesis manuscript.

Avantages

- Subsidized meals
- Partial reimbursement of public transport costs
- Leave: 7 weeks of annual leave + 10 extra days off due to RTT (statutory reduction in working hours) + possibility of exceptional leave (sick children, moving home, etc.)
- Possibility of teleworking (after 6 months of employment) and flexible organization of working hours
- Professional equipment available (videoconferencing, loan of computer equipment, etc.)
- Social, cultural and sports events and activities
- Access to vocational training
- Social security coverage

Rémunération

Monthly gross salary : 2.200 Euros