Interview: 3D modelling Flon river to plan a new metro line
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Rather attracted by the ecology and revitalization of the rivers, Leona Repnik finally specialized in hydraulics at the end of her studies in environmental science and engineering at EPFL.
The desire to learn as much as possible about hydraulic modelling and the communicative enthusiasm for this subject from her master’s project manager, Giovanni De Cesare, will lead her to embark on an unusual project, praised by his supervisors for its excellence. Its objective is to 3D model the Flon River, buried in Lausanne’s basements, with a view to building a future metro line by 2030. The student’s work indicates that the task will not be easy, but that solutions exist.
Her modelling work was specifically focused on the Flon station, in the heart of Lausanne city centre. Here, the tunnel of the future m3 metro is supposed to pass between the ceiling of the historical arch of the river and the Place de l'Europe.
The young graduate’s conclusions are based on a hybrid approach combining 3D numerical modelling, theoretical calculation and a physical model designed at the EPFL Hydraulic Construction Platform. The 3D simulation software enabled her to enter various parameters, including the dimensions of the arch, the properties of water and air, the roughness of the surfaces and the turbulence of the flow. The physical model validated the results. Leona was able to present her master’s project at the international conference SimHydro 2021, held in Nice.