Post-Doctoral Research Visit F - M Wave Transformation From Offshore To The Coast Using The Uhaina Code H/F INRIA

Post-Doctoral Research Visit F/M Wave transformation from offshore to the coast using the UHAINA code
Le descriptif de l'offre ci-dessous est en Anglais
Type de contrat : CDD

Niveau de diplôme exigé : Thèse ou équivalent

Fonction : Post-Doctorant

A propos du centre ou de la direction fonctionnelle

The Inria center at the University of Bordeaux is one of the nine Inria centers in France and has about twenty research teams.. The Inria centre is a major and recognized player in the field of digital sciences. It is at the heart of a rich R&D and innovation ecosystem: highly innovative SMEs, large industrial groups, competitiveness clusters, research and higher education players, laboratories of excellence, technological research institute...

Mission confiée

Assignments

As they propagate from the deep ocean to the coast, waves undergo multiple transformations, the understanding and numerical simulation of which have made significant progress in recent decades. At the regional level, the approach traditionally used to make operational wave forecasts is spectral modeling, which can reproduce the statistical parameters of waves with errors averaging around 10%. However, during rare but highly impact events such as the Hercules storm in January 2014, spectral models can underestimate wave heights by a factor of 2 at the coast, making it impossible to anticipate the associated risks of flooding. For this reason we are focusing in phase-resolved models that are intensively developed the last decades.

As they approach the shore, waves undergo significant changes and they dissipate some of their energy through friction with the bottom and then through breaking, and energy transfers also occur to higher frequencies (higher harmonics) and lower frequencies (GI waves).

In phase-resolved models waves are represented explicitly and allow these phenomena to be reproduced in a much more realistic way (Kazolea et al., 2023; Filippini, 2016). To the best of our knowledge, there are no operational phase-resolved models that are discritized on unstructured meshes and using higher-order techniques. The main reason is the computational time associated with these models which is usually very high.

In this project, we will use the code UHAINA (Filippini et al., 2025) which is an operational hydrodynamic model, combining high-order solutions (mandatory for a correct representation of dispersion), unstructured meshes and a HPC-devoted programming environment able to deal with the requirement of a real area. UHAINA also offers rapid development capabilities to integrate new approaches to improve nearshore wave simulation. The code has been co-developed with INRIA and BRGM and the scales of simulations can be varied from meters to km making this code ideal for coastal simulation and prediction. The hydrostatic part of the model is already used in operational cases while the newly developed non-hydrostatic part has been tested through academic test cases.

We will also combine the acquisition of new field observations (provided by our collaborators) under extreme conditions and numerical simulations with the different available types of models in order to improve our understanding of energy dissipation and transfer phenomena and to simulate waves at the coast more accurately. In particular, the relative importance of these phenomena is strongly controlled by the slope of the seabed, and the Nouvelle Aquitaine Region has the major advantage of having beaches covering a wide range of slopes, very steep in the south and very gentle in the north, which can have complex fore shore morphologies with shoals that significantly alter the waves.

Filippini, A. G. (2016). Free surface flow simulation in estuarine and coastal environments: numerical development and application on unstructured meshes (Doctoral dissertation, Bordeaux)

Andrea Gilberto Filippini, Luca Arpaia, Vincent Perrier, Rodrigo Pedreros, Philippe Bonneton, David Lannes, Fabien Marche, Sebastien De Brye, Simon Delmas, Sophie Lecacheux, Faïza Boulahya, Mario Ricchiuto (2024). An operational discontinuous Galerkin shallow water model for coastal flood assessment, Ocean Modelling, 192.

Kazolea, M., Filippini, A. G., & Ricchiuto, M. (2023). Low dispersion finite volume/element discretization of the enhanced Green-Naghdi equations for wave propagation, breaking and runup on unstructured meshes. Ocean Modelling, 182, 102157.

Principales activités

Main activities (5 maximum) :

- Implement a wave breaking model to the UHAINA code
- Set up and run the code on simple realistic cases
- Run the code on real cases provided by our colleagues.

Compétences

Technical skills and level required :

The candidate must have a PhD in applied mathematics and scientific computing.

Knowledge in programming (C, C++, Fortran or Python) will be highly appreciated.

Languages : English at good working level.

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 partial teleworking 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

Gross remuneration (before deduction of contributions and taxes) : 2788€ / month