Hybrid Modeling of the Massongex-Bex-Rhône Hydropower Plant on the Rhone River in Switzerland

Abstract

Hydropower currently ensures two-thirds of Switzerland’s domestic energy production and aims to gain more importance in the medium and long term due to nuclear abandon. In this respect, the Massongex-Bex-Rhone (MBR) run-of-river hydropower plant project on the Rhone river foresees an annual production of 80 GWh for a design discharge of 220 m³/s. A physical model study was deemed necessary to investigate the functionality and optimization of the novel design concept. A series of preliminary tests to validate the design concept were performed on the physical model. Results showed that the design concept could be validated as satisfactory results were observed in most aspects, but approach flow conditions could be improved to reach better flow distribution across the intake. A 3D numerical model was developed in parallel to test a more significant number of iterations of the design. Once validated, the numerical model was used to test various possible improved geometries, leading to a mixed solution consisting of three main options leading to better approach flow conditions which will be validated on the physical model in the next phase. The present work enhances, for a specific case study the benefits of a hybrid modelling approach, as numerical modelling allows to obtain preliminary results quickly, allowing thus a large number of iterations to be tested before validation of the selected variant on the physical model. This approach increases the efficiency of the design process with a time and cost-effective method.