Recent Publications

The status and design challenges of the heating and current drive systems for DTT

Gustavo Granucci, Silvio Ceccuzzi, Afra Romano, Andrea Murari, Gian Luca Ravera, Piero Agostinetti, Sofia Bertolami, Falk Braunmüller, Alessandro Bruschi, Daniele Busi, et al.

Consorzio RFX, Consiglio Nazionale delle Ricerche, ENEA Agenzia Nazionale per Le Nuove Tecnologie l'Energia e lo Sviluppo Economico Sostenibile, EniProgetti SpA, Ecole Polytechnique Federale de Lausanne

This paper reports the main design keys and the challenging issues of the Heating and Current Drive System (HCD) of the Divert Tokamak Test (DTT) facility that is under construction at ENEA site in Frascati with the aim to perform studies on the power exhaust in a flexible and easily modifiable environment. The selected HCD systems for DTT are those with the most consolidated technology and expected to be relevant for the future reactor. The status of each system is reported, both in terms of design and procurement, which are well advanced for the system required in the first phase of the DTT exploitation: electron and ion cyclotron resonant heating. The third system is neutral beam injector, based on negative ion acceleration, which will be installed in DTT in a second phase, after the first five years of operation. The full heating power will be reached with the doubling of the radiofrequency power to reach the 45 MW at plasma needed to test the divertor with a power density at reactor level.

Remote handling for the DTT divertor: From requirements elicitation to kinematic verification of the Central Cassette End-Effector

Francesco Marino, Andrea Zoppoli, Andrea Fimiani, Francesca Giovanna Lanzotti, Andrea Reale, Giuseppe Di Gironimo

CREATE Consortium, Università degli Studi di Napoli Federico II, DTT S.c.a.r.l., Università degli Studi di Padova, ENEA

Implementation and first application of EMC3-EIRENE on DTT for assessing the heat load on the ICRH antenna

H. S. Wu, Y. Feng, F. Subba, S. Ceccuzzi, P. Innocente, M. M. Robaldo, A. A. Tuccillo, R. Zanino

This paper reports on the implementation process of the three-dimensional (3D) edge plasma transport code EMC3-EIRENE on the Divertor Tokamak Test (DTT) facility and the results of its first application, with a focus on assessing the heat load on the Ion Cyclotron Resonance Heating (ICRH) antenna surfaces. Using axisymmetric geometries and the SOLPS-ITER simulation results as a reference, we first evaluate the performance of the EMC3-EIRENE in describing axisymmetric plasmas to ensure correct code modelling setup for later complex 3D applications. We then incorporate the ICRH antenna structure in our 3D simulations, assuming different toroidal symmetry for the antenna to determine whether the heat load assessment can be carried out with reduced computational effort, and to what extent a 3D assessment deviates from a 2D approximation. The predictions of the 3D antenna heat load distribution are obtained and the peak values on the top plate and the two side plates reach 0.9, 2.1 and 3.8 MW/m2, respectively. Finally, 3D gas puffing is included to evaluate its impact on the antenna heat load. The corresponding 3D edge plasma behavior is presented under the coupled effects of gas puffing and the antenna geometrical structure.

Orbital frequency spectrum and resonant response of realistic tokamak equilibria

Panagiotis Zestanakis, Yannis Antonenas, Giorgos Anastassiou, Matteo Valerio Falessi, Yannis Kominis

National Technical University of Athens, C.R. ENEA Frascati

We present a fast geometric method for calculating guiding center (GC) frequencies in numerical axisymmetric tokamak equilibria. This approach provides a cost-effective means of identifying resonant orbits and offers an intuitive explanation of the role of the equilibrium on the Orbital Frequency Spectrum (OFS) and resonance conditions. We apply the method to two equilibria, one from the ASDEX Upgrade (AUG) and one from the Divertor Tokamak Test facility (DTT) and demonstrate its ability to predict the location of resonant islands under perturbations as well as the existence of transport barriers. Both static non-axisymmetric and time-dependent axisymmetric perturbations are considered. Crucially, the method itself lays the groundwork for developing a reduced-order model for ion transport based on resonance analysis of unperturbed GC dynamics.

Iterative design and preliminary assessment of the DTT vacuum vessel interface to divertor

Andrea Zoppoli, Mauro Dalla Palma, Giuseppe Di Gironimo