Publications associées à Hydropower Plants Frequency Regulation Depending on Upper Reservoir Water Level

Reproducibility Dataset for CRYOWRF v1.0

Michael Lehning, Varun Sharma, Franziska Gerber

This repository contains data required for reproducibility of the results to be published in the associated manuscript. Apart from reproducibility, the attached datasets also serve as templates for new users to adopt CRYOWRF in their research. The datasets ...

2023

Synthesis Report on the Environmental Impacts of Polar Research and Logistics in the Polar Regions

Jérôme Chappellaz

Polar sciences are crucial to understand the effects of climate change. 6 out of 9 eco-tipping points identified by the IPCC are situated in the polar regions. Potential rising sea levels, altered weather patterns and changes in sea-currents are all connec ...

2023

Information-Driven Gas Distribution Mapping for Autonomous Mobile Robots

Alcherio Martinoli, Faezeh Rahbar, Chiara Ercolani

The ability to sense airborne pollutants with mobile robots provides a valuable asset for domains such as industrial safety and environmental monitoring. Oftentimes, this involves detecting how certain gases are spread out in the environment, commonly refe ...

MDPI2023

Basin-scale gyres and mesoscale eddies in large lakes: A novel procedure for their detection and characterization, assessed in Lake Geneva

Ulrich Lemmin, David Andrew Barry, Mehrshad Foroughan, Frédéric Charles Soulignac, Seyed Mahmood Hamze Ziabari

In large lakes subject to the Coriolis force, basin-scale gyres and mesoscale eddies, i.e. rotating coherent water masses, play a key role in spreading biochemical materials and energy throughout the lake. In order to assess the spatial and temporal extent ...

2022

Monitoring Mesoscale to Submesoscale Processes in Large Lakes with Sentinel-1 SAR Imagery: The Case of Lake Geneva

Ulrich Lemmin, David Andrew Barry, Mehrshad Foroughan, Seyed Mahmood Hamze Ziabari

As in oceans, large-scale coherent circulations such as gyres and eddies are ubiquitous features in large lakes that are subject to the Coriolis force. They play a crucial role in the horizontal and vertical distribution of biological, chemical and physica ...

2022

Modeling the small-scale deposition of snow onto structured Arctic sea ice during a MOSAiC storm using snowBedFoam 1.0

Michael Lehning, Marc Schneebeli Zeugin, Océane Hames, Mahdi Jafari, David Nicholas Wagner

The remoteness and extreme conditions of the Arctic make it a very difficult environment to investigate. In these polar regions covered by sea ice, the wind is relatively strong due to the absence of obstructions and redistributes a large part of the depos ...

COPERNICUS GESELLSCHAFT MBH2022

Gyrokinetic simulations of turbulence and zonal flows driven by steep profile gradients using a delta-f approach with an evolving background Maxwellian

Stephan Brunner, Laurent Villard, Alberto Bottino, Ben McMillan, Moahan Murugappan

Long global gyrokinetic turbulence simulations are particularly challenging in situations where the system deviates strongly from its initial state and when fluctuation levels are high, for example, in strong gradient regions. For particle-in-cell simulati ...

2022

A Collaborative Workflow to Automate the Design, Analysis, and Construction of Integrally-Attached Timber Plate Structures

Pierre Latteur, Yves Weinand, Aryan Rezaei Rad, Petras Vestartas, Nicolas Henry Pierre Louis Rogeau

This paper introduces a computational framework that fosters collaboration between architects, engineers, and contractors by bridging the gap between architectural design, structural analysis, and digital construction. The present research is oriented towa ...

CAADRIA2022

Flexibilisation of Biogas-Based Power-to-Gas Processes: A Techno-Economic and Experimental Assessment

Andreas Gantenbein

Biogas-based power-to-X technology allows storing renewable electricity, while producing CO2-neutral products. This work investigates the conversion and upgrading of digestion-derived gas mixtures with focus on increasing the operational flexibility of the ...

EPFL2022

Detecting submesoscale cold filaments in a basin-scale gyre in large, deep Lake Geneva (Switzerland/France)

Ulrich Lemmin, David Andrew Barry, Amir Mehdi Razmi, Seyed Mahmood Hamze Ziabari

Submesoscale filaments are a well-documented feature of oceanic flow fields. Based on the analysis of high-resolution 3D numerical simulations, field observations and remote sensing imagery, this study, carried out in Lake Geneva, Western Europe's largest ...

2022

Modelling the small-scale deposition of snow onto structured Arctic sea ice during a MOSAiC storm using snowBedFoam 1.0

Michael Lehning, Marc Schneebeli Zeugin, Océane Hames, Mahdi Jafari, David Nicholas Wagner

The remoteness and extreme conditions of the Arctic make it a very difficult environment to investigate. In these regions, the wind has a substantial effect and redistributes a large part of the snow, which complicates precipitation estimates. Moreover, th ...

2021

Reduced-order Models for Simulating Coupled Geometric Instabilities in Steel Beam-columns Under Inelastic Cyclic Straining

Alexander Riley Hartloper

Numerical models that can simulate coupled geometric instabilities in steel beam-columns are required for the seismic assessment of certain steel moment-resisting frames. Reliably simulating coupled instabilities requires that the steel material is precise ...

EPFL2021

Introducing CRYOWRF v1.0: multiscale atmospheric flow simulations with advanced snow cover modelling

Michael Lehning, Varun Sharma, Franziska Gerber

Accurately simulating snow-cover dynamics and the snow-atmosphere coupling is of major importance for topics as wide-ranging as water resources, natural hazards and climate change impacts with consequences for sea-level rise. We present a new modelling fra ...

2023

Increasing Superstructure Optimization Capacity Through Self-Learning Surrogate Models

François Maréchal, Ivan Daniel Kantor, Julia Granacher

Simulation-based optimization models are widely applied to find optimal operating conditions of processes. Often, computational challenges arise from model complexity, making the generation of reliable design solutions difficult. We propose an algorithm fo ...

2021

Self-learning surrogate models in superstructure optimization

François Maréchal, Ivan Daniel Kantor, Julia Granacher, Michel Lopez

In this contribution, we propose an algorithm for replacing non-linear process simulation integrated in multi-level optimization of an energy system superstructure with surrogate models. With our approach, we demonstrate that surrogate models are a valid t ...

Elsevier2021

Drift-related transport and plasma-neutral interaction in the TCV divertor

Mirko Wensing

Thermonuclear fusion of light atoms is the primary energy source of stars, such as our Sun, that led to the emergence of life on Earth. However, its economic exploitation as a virtually unlimited and clean energy source is yet to be developed. One of the m ...

EPFL2021

Numerical simulations of Pelton turbine flow to predict large head variation influence

François Avellan, Steve Crettenand, Cécile Münch-Alligné, Siamak Alimirzazadeh

In the framework of the new feed-in-tariff system in Switzerland for Small Hydropower Plants (SHP), the aim of the SmallFLEX project, led by HES-SO Valais and performed in collaboration with EPFL, WSL, EAWAG, PVE, and FMV, is to show how SHP can provide wi ...

IOP PUBLISHING LTD2021

Numerical Simulations of an Innovative Water Stirring Device for Fine Sediment Release: The Case Study of the Future Trift Reservoir

Pedro Filipe De Almeida Manso, Azin Amini, Anass Chraibi

Reservoir sedimentation and consequently lack of storage volume and perturbation of the operation of intakes and bottom outlet is a key challenge affecting both hydropower production as well as dam safety and flood management. In the framework of a peer-re ...

Springer2020

Resistivity of REBCO tapes in overcritical current regime: impact on superconducting fault current limiter modeling

Bertrand Dutoit, Bertrand Dutoit, Francesco Grilli, Frédéric Sirois, Nicolo' Riva

A detailed knowledge of the resistivity of high-temperature superconductors in the overcritical current regime is important to achieve reliable numerical simulations of applications such as superconducting fault current limiters. We have previously shown t ...

2020

Modeling Compact Intracloud Discharge (CID) as a Streamer Burst

Farhad Rachidi-Haeri, Marcos Rubinstein

Narrow Bipolar Pulses are generated by bursts of electrical activity in the cloud and these are referred to as Compact Intracloud Discharges (CID) or Narrow Bipolar Events in the current literature. These discharges usually occur in isolation without much ...

2020