Publications by René Chavan | EPFL Graph Search

Conceptual design proposal for the EU-DEMO electron cyclotron ex-vessel waveguide system with enhanced remote maintainability

René Chavan, Jean-Philippe Hogge, Avelino Mas Sanchez, Anastasia Xydou

The EUropean DEMOnstration power plant (EU-DEMO) project, a EUROfusion initiative, seeks to advance fusion power technology by developing a reliable Electron Cyclotron (EC) heating and current drive system capable of delivering up to 130 MW of auxiliary he ...

2025

Effect of Ion Irradiation on the Surface Electrical Conductivity of Cucrzr at High Frequencies

René Chavan, Timothy Goodman, Jean-Philippe Hogge, Jérémy Genoud, Avelino Mas Sanchez, Anastasia Xydou

The ohmic losses in the Electron Cyclotron Heating system of the DEMO nuclear fusion reactor depend on the surface electrical conductivity of the material at the frequency of the mm-wave beams generated in the gyrotrons. To reduce the ohmic losses, many co ...

ELSEVIER SCIENCE SA2025

Design description and thermo-hydraulic assessment of the steering mirror for the EU DEMO Electron Cyclotron system

René Chavan, Jean-Philippe Hogge, Avelino Mas Sanchez, Anastasia Xydou

Six Electron Cyclotron (EC) launchers are currently envisaged to be installed at the Equatorial Ports (EP) of the EU DEMO Tokamak with the purpose of delivering up to 130 MW for plasma bulk heating (BH), thermal instability (TI) control and magnetohydrodyn ...

2025

Pre-conceptual design of the fixed mirrors for the DEMO Electron Cyclotron Heating antenna

René Chavan, Timothy Goodman, Jean-Philippe Hogge, Avelino Mas Sanchez, Anastasia Xydou, Humberto Torreblanca Quiroz

The M1 mirrors are part of the in -vessel quasi -optical Electron Cyclotron beam propagation system of the DEMO nuclear fusion reactor. These four mirrors are all non -movable and with a plane reflecting surface. Based on their functionality they are divid ...

Elsevier Science Sa2024

Pre-conceptual design of the steering mirror for the DEMO electron cyclotron heating system

René Chavan, Timothy Goodman, Jean-Philippe Hogge, Avelino Mas Sanchez, Anastasia Xydou

An Electron Cyclotron (EC) Heating and Current Drive (HCD) system will be installed in the EU DEMO Tokamak to provide plasma heating and stabilization by coupling up to 130 MW of mm-wave power into specific regions of the plasma. The mm -waves will be gene ...

Elsevier Science Sa2024

Conceptual design of a modular EC heating system for EU-DEMO

René Chavan, Timothy Goodman, Jean-Philippe Hogge, Anastasia Xydou

The European DEMO (EU-DEMO) reactor studies within EUROfusion aim to develop a fusion power plant concept. The large tokamak device needs an auxiliary heating power which, at the present stage, is provided by the Electron Cyclotron (EC) heating system with ...

IOP Publishing Ltd2024

Design Progress of Structural Components of the EU DEMO EC Equatorial Launcher

René Chavan, Jean-Philippe Hogge

The EU DEMO Tokamak is foreseen to be equipped with an electron cyclotron (EC) system for plasma heating, magnetohydrodynamic (MHD) control, and thermal instability suppression. Up to six launchers will be installed into equatorial ports with the aim to in ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Fluid-dynamic and thermo-mechanical analyses of the ITER electron cyclotron Miter bend mirror for the off-centered beam scenario

René Chavan, Timothy Goodman, Avelino Mas Sanchez, Anastasia Xydou, Humberto Torreblanca Quiroz

2023

Present design of the Steering Mirror Assembly (SMA) for ITER ECHUL

René Chavan, Timothy Goodman, Anastasia Xydou

In the ITER Tokamak, four Electron Cyclotron Heating Upper Launchers (ECHUL) are needed to control plasma instabilities at the rational surfaces, most importantly the q = 3/2 and q = 2/1 neoclassical tearing modes (NTMs). Each ECHUL is equipped with a set ...

2023

High power mm-wave loss measurements of ITER ex-vessel waveguide components at the FALCON test facility at the Swiss Plasma Center

René Chavan, Timothy Goodman, Avelino Mas Sanchez, Anastasia Xydou, Humberto Torreblanca Quiroz

Many future fusion devices will rely heavily, if not solely, on electron cyclotron (EC) heating subsystems to provide bulk heating, instability control (neoclassical tearing mode (NTM) stabilization), and thermal instability control. Efficient use of the i ...

E D P SCIENCES2023

Prototype mitre bends of the ex-vessel waveguide system for the ITER upper launcher: Thermal hydraulic simulations and experiments with off-center mm-wave beams

René Chavan, Timothy Goodman, Matteo Vagnoni, Anastasia Xydou, Humberto Torreblanca Quiroz

On ITER, long pulse gyrotrons are required as a power source for electron cyclotron heating (ECH) and current drive (CD). The microwaves are guided from the gyrotrons, which are placed far from the Tokamak, into the plasma by transmission lines (TLs) and a ...

2021

Neutronics Analyses of EU DEMO 2020 EC Port Configuration

René Chavan, Minh Quang Tran

The DEMOnstration fusion power plant (DEMO) is being developed within EUROfusion and one of the challenges is the integration of all the systems into a fusion reactor by designs that meet strict design criteria required for safe and reliable long-term reac ...

NUCLEAR SOCIETY SLOVENIA2021

Design optimization of the Upper Steering Mirror Assembly (USMA) for ITER ECHUL in view of disruptive events

René Chavan, Timothy Goodman, Matteo Vagnoni, Anastasia Xydou

Four Electron Cyclotron Heating Upper Launchers (ECHUL) will be used at ITER to counteract magneto-hydrodynamic plasma instabilities by targeting them with up to 20 MW of mm-wave power at 170 GHz. The millimeter waves are guided through a set of fixed mirr ...

2021

Integration concept of an Electron Cyclotron System in DEMO

René Chavan, Minh Quang Tran, Hartmut Zohm, Konstantinos Avramidis

The pre-conceptual layout for an electron cyclotron system (ECS) in DEMO is described. The present DEMO ECS considers only equatorial ports for both plasma heating and neoclassical tearing mode (NTM) control. This differs from ITER, where four launchers in ...

2021

Structural pre-conceptual design studies for an EU DEMO equatorial EC port plug and its port integration

René Chavan, Minh Quang Tran

For the EU DEMO Tokamak, Electron Cyclotron (EC) launching systems for plasma heating and stabilization are under development. Various concepts for the optical system are currently studied of which the Mid Steering Antenna (MSA) with a steering mirror at a ...

Elsevier2020

Design and Thermal-Structural Analyses of Ancillary Components for the Optical Steering Mirror (M4) for the ITER ECH Upper Launcher

René Chavan, Timothy Goodman, Avelino Mas Sanchez, Matteo Vagnoni

Each of the four ITER Electron Cyclotron Heating Upper Launcher (ECHUL) features eight transmission lines (TLs) that are used to inject 170-GHz microwave power into the plasma at a level of up to 1.31 MW (at the TL diamond window) per line. The millimeter ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2020

Electromagnetic and mechanical analyses of the ITER electron cyclotron Upper launcher steering M4 mirrors for the vertical displacement event

René Chavan, Timothy Goodman, Avelino Mas Sanchez, Matteo Vagnoni

The mm-wave power exiting the eight In-Vessel waveguides inside the ITER Electron Cyclotron Upper Launcher is reflected by three fixed mirror sets and finally aimed by two independent steering mirrors to specific plasma locations. A design solution for bot ...

2020

High-Power Testing of Guided-Wave Components for the ITER ECH Upper Launcher at the FALCON Test Facility

René Chavan, Timothy Goodman, Matteo Vagnoni

Each of the four ITER electron cyclotron heating (ECH) upper launchers (ULs) features eight transmission lines (TLs) made of guided-wave components used to inject 170-GHz microwave power into the plasma at a level of up to 1.31 MW per line, at the TL diamo ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2020

Design Concept and Thermal & x2013;Mechanical Analysis of the Optical Mirror (M3) for the ITER ECH Upper Launcher

René Chavan, Timothy Goodman, Avelino Mas Sanchez

The mirror M3 is a part of the in-vessel quasi-optical beam propagation system for the ITER electron cyclotron heating upper launcher (ECHUL). The millimeter waves are guided through fixed mirror sets (M1, M2, and M3) and the front steering mirror set (M4) ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2020

Structural integrity assessment of an ITER ECH&CD Upper Launcher mirror (LM1)

René Chavan, Timothy Goodman, Matteo Vagnoni

2019