Developed since 1987 by EDF R&D in collaboration with other French, European and international organisations, the openTELEMAC system is a set of scientific computation solvers, coupled and parallelized, dedicated to the modelling of free surface environmental hydraulics. It can carry out simulations of flows, sediment transports, waves and water quality. The system has gradually evolved to the notion of hydro-informatics with a set of solvers dealing with large heterogeneous data and solving complex dependent problems. The various simulation components use high-end algorithms based on the finite element or finite volume methods. The ability to study global, regional, or local scale problems by using the same system, makes openTELEMAC a useful tool for assessing the environmental state in the sea, estuaries, coastline, lakes and rivers.
The openTELEMAC system
The openTELEMAC system is composed of the following components, each of which relates to a specific physics, and all of which are coupled together to simulate complex environmental systems:
- MASCARET – 1D hydraulic modelling based on Saint‑Venant equations, suitable for river networks and flood propagation
- TELEMAC-2D – two‑dimensional shallow water modelling for free‑surface flows
- TELEMAC-3D – three‑dimensional hydrodynamics based on Navier‑Stokes equations
- ARTEMIS – wave agitation in coastal and portal areas
- TOMAWAC – wave generation and propagation modelling
- COURLIS – sediment transport and morphodynamic evolution coupled with MASCARET
- GAIA – sediment transport and morphodynamic evolution coupled with TELEMAC-2D or TELEMAC-3D
- TRACER – tracer transport coupled with TELEMAC-2D or TELEMAC-3D
- KHIONE – ice modelization coupled with TELEMAC-2D or TELEMAC-3D
- WAQTEL – water quality coupled with TELEMAC-2D or TELEMAC-3D
- NESTOR – sediment dredging modelisation
The environment around openTELEMAC
Surrounding the openTELEMAC system solvers and also distributed as open source codes, an ensemble of scripts entirely written in Python have been developed to allow the environmental modeling system to meet the challenges of complex real-world problems. In this framework, distributed Application Programming Interface (API) of the openTELEMAC system with a Python overlay has been developed. This Python wrapping of openTELEMAC system API constitutes a package called TELAPY (documentation) distributed in the official version of the hydro-informatic system.
Why use openTELEMAC?
- Development & community: an open‑source system developed and maintained by an international consortium of research institutes and engineering organisations, ensuring continuous evolution, shared expertise and long-term reliability
- Technical capabilities: relies on finite element and finite volume methods on unstructured meshes, allowing accurate modelling of complex geometries such as floodplains, estuaries and river networks; dedicated solvers (1D, 2D, 3D) can be combined depending on the problem; designed for parallel execution on HPC systems
- Multi-physics modelling: supports coupled simulations of hydrodynamics, waves, sediment transport and tracers (e.g. temperature, salinity or pollutants) within a single framework, enabling consistent representation of interacting processes
- Wide range of uses: applied in real-world studies such as flood modelling in river basins, coastal circulation and harbour design, sediment transport and morphodynamic analysis, or transport of tracers in environmental systems
- Practical value: suitable for both research and engineering workflows, from local detailed studies (e.g. floodplain dynamics, harbour basins) to regional or large-scale systems using the same modelling framework