Speaker
Description
In present and future magnetic confinement fusion devices, Electron Cyclotron Emission (ECE) diagnostics are key for the measurement of the electron temperature profile and its fluctuations, often providing data complementary to Thomson Scattering systems. By virtue of their fast time response, ECE diagnostics also provide indispensable information for plasma operation, through real-time measurement of temperature profiles, and characterizing the temperature perturbations due to plasma instabilities.
Being able to simulate the behaviour of diagnostics on ITER is essential to predict their performance and to develop the modelling tools used to design relevant scenarios and control strategies. Developing such a modelling platform is one of the main purposes of the ITER Integrated Modelling and Analysis Suite, IMAS [1]. Diagnostic models, also called synthetic diagnostics (SD), play an important role in plasma simulators, generating signals in the same form as they will be used to control the plasma and measure its performance during ITER operation.
The results obtained from ECE modelling can potentially enhance the overall understanding of plasma behaviour in ITER, and in particular allow the sensitivity of ECE measurements for the detection of Neoclassical Tearing Models (NTMs) to be quantified.
The SPECE code has been developed to simulate ECE in tokamaks, using a ray-tracing model to solve the radiation transport equation along ray trajectories in a tokamak plasma [2].
This contribution presents the work carried out to adapt the SPECE code to IMAS, to enable its use in integrated modelling workflows developed by the fusion community and to assess the measurement capabilities of the ECE diagnostic for various scenario conditions. This code adaptation allows its application to scenarios from the IMAS scenario database, taking its input from the core_profiles and equilibrium Interface Data Structures (IDS), combined with the ece IDS read from the Machine Description database to receive the geometry of the ITER ECE diagnostic. The SPECE simulation results, which consist of ECE synthetic data, are then stored as scenario output in the ece IDS.
The IMAS integrated SPECE model has been applied to a variety of ITER Research Plan scenarios. As an illustration, the frequency wave spectrum and the local measurement of temperature along the diagnostic line-of-sight will be presented and discussed.
The views and opinions expressed herein do not necessarily reflect those of the ITER Organization.
