arXiv subjects

P. Innocente

Publications and source records attributed to P. Innocente.

3 recordsLinked to original sources

arXiv2026

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

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.

physics.plasm-ph↗

arXiv2018

Fluctuation characteristics of the TCV snowflake divertor measured with high speed visible imaging

Tangentially viewing fast camera footage of the low-field side snowflake minus divertor in TCV is analysed across a four point scan in which the proximity of the two X-points is varied systematically. The motion of structures observed in the post- processed movie shows two distinct regions of the camera frame exhibiting differing patterns. One type of motion in the outer scrape-off layer remains present throughout the scan whilst the other, apparent in the inner scrape-off layer between the two nulls, becomes increasingly significant as the X-points contract towards one another. The spatial structure of the fluctuations in both regions is shown to conform to the equilibrium magnetic field. When the X-point gap is wide the fluctuations measured in the region between the X-points show a similar structure to the fluctuations observed above the null region, remaining coherent for multiple toroidal turns of the magnetic field and indicating a physical connectivity of the fluctuations between the upstream and downstream regions. When the X-point gap is small the fluctuations in the inner scrape-off layer between the nulls are decorrelated from fluctuations upstream, indicating local production of filamentary structures. The motion of filaments in the inter-null region differs, with filaments showing a dominantly poloidal motion along magnetic flux surfaces when the X-point gap is large, compared to a dominantly radial motion across flux-surfaces when the gap is small. This demonstrates an enhancement to cross-field tranport between the nulls of the TCV low-field-side snowflake minus when the gap between the nulls is small.

physics.plasm-ph↗

arXiv2009

The plasma boundary in Single Helical Axis RFP plasmas

Single Helical Axis (SHAx) states obtained in high current reversed field pinch (RFP) plasmas display, aside from a dominant mode in the m=1 spectrum, also a dominant m=0 mode, with the same toroidal mode number as the m=1 one. The two modes have a fixed phase relationship. The island chain created by the m=0 mode across the reversal surface gives rise, at shallow reversal of the toroidal field, to an X-point structure which separates the last closed flux surface from the first wall, creating a divertor-like configuration. The plasma-wall interaction is found to be related to the connection length of the field lines intercepting the wall, which displays a pattern modulated by the dominant mode toroidal periodicity. This configuration, which occurs only for shallow toroidal field reversal, could be exploited to realize an island divertor in analogy to stellarators.

physics.plasm-ph↗