| No |
Davide Mancini (davide.mancini@epfl.ch), Paolo Ricci (paolo.ricci@epfl.ch) |
Theory |
TCV |
Turbulence simulations of Doublets with the GBS code |
Modelling and analysis of the plasma turbulence in the SOL of a tokamak device in different Doublets magnetic configurations, based on recent experiments performed in TCV.
|
Armand Laville (armand.laville@epfl.ch) |
| No |
Davide Mancini (davide.mancini@epfl.ch), Paolo Ricci (paolo.ricci@epfl.ch) |
Theory |
TCV |
Time dependent neutral solver in KINDNES |
Analysis and implementation of a neutral solver that doesn't use the adiabatic approximation in the framework of KINDENS, a deterministic neutral dynamics solver for plasma turbulence simulations. |
Matyas Rodriguez Szonyi (matyas.rodriguezszonyi@epfl.ch) |
| Yes |
Francesco Carpanese (francesco.carpanese@epfl.ch) |
Data analysis, modelling, machine learning |
TCV |
Exploration of the FGS free-boundary solution space and development of an ML surrogate |
The free-boundary solver FGS provides the initial equilibrium used in time-dependent free-boundary simulations for testing magnetic controllers on TCV. Because the underlying nonlinear problem admits multiple solutions, FGS convergence depends strongly on the proximity between these solutions and on the quality of the initial guess. This often complicates obtaining the desired starting plasma for evolutive simulations. This project will systematically investigate how many alternative solutions exist near a given equilibrium, and how sensitive they are to input parameters, across a broad range of plasma conditions. The resulting large-scale database will enable training a machine-learning surrogate model for FGS. This surrogate is expected to support Bayesian equilibrium reconstruction and accelerate the evolutive free-boundary solver FGE. |
|
| Yes |
Francesco Carpanese (francesco.carpanese@epfl.ch) |
Data analysis, modelling, machine learning |
TCV |
Bayesian magnetic and kinetic equilibrium reconstruction for TCV |
Equilibrium reconstruction infers the plasma shape from magnetic measurements, typically via the nonlinear least-squares solver LIUQE, which uses a frequentist uncertainty model. A Bayesian formulation, although more computationally demanding, provides principled uncertainty of quantification and naturally incorporates heterogeneous diagnostic measurements with proper error propagation. This approach has gained traction in recent years and was previously prototyped for TCV. With the tools now available at SPC, the Bayesian analysis could use a forward model constrained by physical assumptions on the internal current-density profile, enabling a more realistic reconstruction of the safety-factor profile q, which is crucial for many aspects of tokamak operation. This workflow hasn't been developed yet and will benefit several analysis for tokamak operation. |
|
| Yes |
Duccio Testa (duccio.testa@epfl.ch) |
Hardware, experimental |
DEMO, DTT
|
Design and prototyping of a high-frequency magnetic sensor for current and future tokamaks, combining photolithography and Hall technologies |
The project involves prototyping activities using different technologies, mostly available in-house at the EPFL, and testing of the as-built prototypes. This in turn will be used to define the final design and the manufacturing and testing specifications for the actual magnetic sensors for DEMO and DTT. |
|
| Yes |
Duccio Testa (duccio.testa@epfl.ch) |
Data analysis, experimental |
TCV |
EM and ES fluctuation measurements |
Advanced statistical analyses of EM and ES fluctuation measurements on TCV, focussing on the role of the plasma shape and magnetic helicity in affecting the stability of ES and EM turbulence. |
|
| Yes |
Duccio Testa (duccio.testa@epfl.ch) |
Data analysis, experimental |
TCV |
Data analysis for the TCV fast ion experiments: gap structure vs. onset of fast ion drives modes vs. plasma shape, positive & negative triangularity |
Analysis of the role of the plasma shape in affecting the stability of electro-magnetic and electro-static macroscopic instabilities driven by fast ions |
|
| Yes |
Duccio Testa (duccio.testa@epfl.ch) |
Theory, data analysis |
TCV, ITER |
Analysis of the phase-space stability of transport simulations in TCV |
Use the Phase-Space-Reconstruction approach, and the ensuing evolution of the Lyapunov exponents, as a tool to determine whether a pre-programmed discharge is evolving towards or diverging from a stable attractor in phase space, and on what time scales this would happen. This will be done using ASTRA and/or RAPTOR transport simulations of TCV tokamak discharges, and if time allows then using comparison with electro-magnetic and electro-static fluctuation measurements in such pre-programmed discharges as then actually run on TCV. |
|
| Yes |
Duccio Testa (duccio.testa@epfl.ch) |
Numerical, data analysis |
TCV, ITER, DEMO, DTT |
Development of a "universal" GUI for MHD analyses |
All magnetic fusion experiments require the analysis of the magnetohydrodynamic perturbation to the plasma equilibrium, and there is a set of mathematical and computational tools that can be universally adapted to all such experiments, existing and futures. Starting form existing codes, we wish to prepare a user-friendly software package, such as a Graphical User Interface (GUI), that could be generally adapted and thus deployed to multiple experiments. |
|
| Yes |
Duccio Testa (duccio.testa@epfl.ch) |
Numerical, data analysis |
DEMO, DTT |
Assessment of the long-term performance of the magnetic diagnostic systems in DEMO and DTT |
Develop an assessment of a general concept for the overall magnetic diagnostic system satisfying the intended measurement requirements for DEMO and DTT, specifically designed considering the long-term but cost-effective resilience of the measurement performance to the inevitable loss of sensors. |
|
| Yes |
Benoit Labit (benoit.labit@epfl.ch) |
Theory, data analysis |
TCV, possibly JET |
Role of MHD in pedestal structure for various H-mode regime |
The details of the project will be discussed with the candidate but the main idea is to use numerical tools (MHD codes) to evaluate the pedestal stability and MHD induced transport for either TCV or JET cases. |
|
| Yes |
Reinart Coosemans (reinart.coosemans@epfl.ch), Benoit Labit (benoit.labit@epfl.ch) |
Data analysis, modeling |
TCV |
Neutron rate estimates for TCV plasmas with RABBIT code |
In plasmas heated with deuterium beams a deficit of the expected fusion neutron rate is an indicator of the deterioration of the fast-ion confinement, caused, for instance, by magnetohydrodynamic instabilities. The goal of the project is to estimate the neutron rate for TCV plasmas using the code RABBIT (rt-capable) and to compare the results with experimental data and with other codes like NUMEAM (which is more slower). If the results are encouraging, a coupling with transport codes like ASTRA could be envisaged. |
|
| Yes |
Anton Jansen Van Vuuren (anton.jansenvanvuuren@epfl.ch), Benoit Labit (benoit.labit@epfl.ch) |
Data analysis, modeling |
TCV |
Refined charge-exchange losses estimates for fast ions for TCV plasmas |
In fusion plasmas, a precise knowing of the loss power is crucial to assess the quality of the confinement. One source of losses is charge-exchange (CX) between the fast ions and the background “cold” neutrals. The goal of the project is to evaluate CX losses for TCV plasmas (using ASCOT code) assuming a more realistic neutral density spatial distribution (from SOLPS simulations). At TCV, a large SOLPS database exists, in particular for plasma detachment where plasma density is increased by large injection of deuterium neutral molecules. Results will be compared to estimates from ASTRA simulations, the used standard tool at TCV. |
|
| Yes |
Benjamin Vincent (benjamin.vincent@epfl.ch) |
Experimental, data analysis |
TCV |
Experimental characterization and commissioning of a new system based spectral apodization filter for the Incoherent Thomson Scattering (ITS) diagnostic |
Previous simulation work has demonstrated the feasibility and benefits of using a single-filter/two-spectral-channels system for analyzing scattered light from ITS. When analytically optimized to spectrally apodize the ITS spectrum in specific ways, simulation for such a setup has suggested it would offer performance similar to or even better than a polychromator. It has also been demonstrated that, in some cases, such a tool could be a promising candidate for assessing velocity profiles. The student would be involved in the characterization of such a filter design and its implementation at TCV inside an existing polychromator system, in order to validate the sensitivity improvements predicted by simulation. |
|
| Yes |
Guillaume Van Parys (guillaume.vanparys@epfl.ch) |
Theory |
TCV |
MHD stability of shaped, rotating, pressure anisotropic plasmas |
Coupling of ideal MHD stability code VENUS-MHD to new equilibrium solver with rotation pressure anisotropy. |
|